Land Protection Plan

San Luis Valley Conservation Area

Colorado and New Mexico 

December 2015

Prepared by

San Luis Valley National Wildlife Refuge Complex 

8249 Emperius Road 

Alamosa, CO 81101 

719 / 589 4021 

 U.S. Fish and Wildlife Service 

Region 6, Mountain-Prairie Region 

Branch of Refuge Planning 

134 Union Boulevard, Suite 300 

Lakewood, CO 80228 

303 / 236 8145

CITATION for this document:

U.S. Fish and Wildlife Service. 2015. Land protection plan for the San Luis Valley Conservation Area. Lakewood, CO: U.S. 

Department of the Interior, U.S. Fish and Wildlife Service. 151 p.
In accordance with the National Environmental Policy Act and U.S. Fish and Wildlife Service policy, an 

environmental assessment and land protection plan have been prepared to analyze the effects of establishing 

the San Luis Valley Conservation Area in southern Colorado and northern New Mexico. 

The environmental assessment (appendix A) analyzes the environmental effects of establishing the San Luis 

Valley Conservation Area. 

The San Luis Valley Conservation Area land protection plan describes the priorities for acquiring up to 

250,000 acres through voluntary conservation easements and up to 30,000 acres in fee title.

Note: Information contained in the maps is approximate and does not represent a legal survey. 

Ownership information may not be complete.
Contents

Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Chapter 1—Introduction and Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Purpose of the San Luis Valley Conservation Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Vision for the San Luis Valley National Wildlife Refuge Complex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Purpose of the Alamosa and Monte Vista National Wildlife Refuges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Purpose of the Baca national wildlife refuge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Purpose of the Sangre de Cristo Conservation Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Issues Identified and Selected for Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Public Review of and Comments on the Draft EA and LPP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

National Wildlife Refuge System and Authorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Related Actions and Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

San Luis Valley National Wildlife Refuge Complex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

U.S. Fish and Wildlife Service—Partners for Fish and Wildlife Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

USDA Forest Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Bureau of Land Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

National Park Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Natural Resources Conservation Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

State of Colorado . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Land Trusts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Habitat Protection and theEasement Acquisition Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Conservation Easements and Other Acquisitions.................................................... 10

Chapter 2—Area Description and Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Physical Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Water and Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Biological Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Plant Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Wildlife . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Cultural Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Prehistory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Early History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Political Boundaries, Land Grants, and Public Lands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Native Peoples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Settlement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Summary of Known Historic Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Socioeconomic Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Socioeconomic Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Land Use and Ownership Changes Surrounding the conservation area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

San luis valley conservation area land conservation efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Water Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
iv Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Chapter 3—Threats to and Status of Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Threats to Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Invasive Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Water Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Cultural Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Climate Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Effects on the Natural and Human Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Chapter 4—Project Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Land Protection Choices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

No Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Conservation easements and limited fee-title acquisition (preferred alternative) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Project Objectives and Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Collaboration with Land Protection Organizations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Easement Terms and Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Contaminants or Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Acquisition money . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Incorporating Science and Strategic Habitat Conservation in the SLVCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Strategic Growth of the National Wildlife Refuge System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Strategic Habitat Conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Protection Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Species-Habitat Mapping Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Landscape Prioritization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Evaluation of Easement Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Socioeconomic Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Public Involvement and Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Scoping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Public Review of the Draft Environmental Assessment and Land Protection Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Distribution and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Glossary................................................................................. 63

 Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Appendix C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Appendix D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Appendix E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Contents v

FIGURES

Figure 1. Overview map of the general land cover of the San Luis Valley Conservation Area in Colorado and 

New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Figure 2. Map of the San Luis Valley Conservation Area, which will be part of a broader network of public 

and private conservation lands in Colorado and New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 3. Map of the San Luis Valley and Sangre de Cristo Conservation Areas in Colorado and New Mexico,

which capture the upper headwaters of the Rio Grande, the fourth longest river in the United States. . . . . . . . . 13

Figure 4. Spatial graphic of predicted distribution of the New Mexico meadow jumping mouse in the 20th 

century and the late 21st century in the San Luis Valley Conservation Area, Colorado and New Mexico. . . . . . . 47

Figure 5. Map of southwestern willow flycatcher and Canada lynx habitat in the San Luis Valley Conservation 

Area, Colorado and New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Figure 6. Map of Rio Grande cutthroat trout habitat in the San Luis Valley Conservation Area, Colorado and 

New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Figure 7. Map of present Gunnison sage-grouse habitat in and around the San Luis Valley Conservation Area, 

Colorado and New Mexico, with historical range indicated for reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Figure 8. Map of Wilson’s phalarope habitat in the San Luis Valley Conservation Area, Colorado and New Mexico. . . 56

Figure 9. Map of American bittern habitat in the San Luis Valley Conservation Area, Colorado and New Mexico. . . 58

Figure 10. Map of sage thrasher habitat in the San Luis Valley Conservation Area, Colorado and New Mexico. . . . . 59

Figure 11. Map of spatial conservation prioritization within the San Luis Valley Conservation Area, Colorado and 

New Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

TABLES

Table 1. Population statistics for counties in Colorado and New Mexico that contain the San Luis Valley

Conservation Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Table 2. Income, education, unemployment, and poverty rates for counties in Colorado and New Mexico

that contain the San Luis Valley Conservation Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Table 3. Percentage employment by sector for counties in Colorado and New Mexico that contain the 

San Luis Valley region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Table 4. Resident, migratory, and breeding birds of concern within the San Luis Valley Conservation Area, Colorado

and New Mexico, with their status and objectives from a relevant continental or regional plan or list. . . . . . . . 49

Abbreviations

BLM Bureau of Land Management

CCP Comprehensive conservation plan

CFR Code of Federal Regulations

DOE Department of Energy

EA Environmental assessment

LPP Land protection plan

NASA National Aeronautics and Space Administration

NEPA National Environmental Policy Act

NPS National Park Service

NRCS Natural Resource Conservation Service

SCCA Sangre de Cristo Conservation Area

Service U.S. Fish and Wildlife Service

SLVCA San Luis Valley Conservation Area

U.S.C. United States Code

USFS USDA Forest Service

USFWS U.S. Fish and Wildlife Service

USGS U.S. Geological Survey

Chapter 1—Introduction and 

Project Description

In short, this view combined the sublime and 

beautiful: the great and lofty mountains covered with eternal snows, seemed to surround 

the luxuriant vale, crowned with perennial 

flowers, like a terrestrial paradise, shut out 

from the view of man.

—Captain Zebulon Pike, on a hill overlooking the 

San Luis Valley, February 5, 1807

Through the San Luis Valley Conservation Area 

(SLVCA), we, the U.S. Fish and Wildlife Service 

(Service) will join our partners in protecting the 

remarkable ecological values and working landscapes 

of the high mountain desert that were so eloquently 

described during Pike’s Expedition to the Southwest 

in the early 19th century. The SLVCA is a landscapelevel strategic habitat conservation initiative within the 

boundaries of the Southern Rockies Landscape Conservation Cooperative. The conservation area encompasses the headwaters of the Rio Grande in southern 

Colorado and a small part of northern New Mexico. 

Despite substantial changes that have altered its 

landscape and ecology, the San Luis Valley is a remarkable North American example of the compatibility of 

wildlife and agriculture. Due to the low human population associated with the mostly agricultural economy, 

the existing wetland, riparian, and upland habitats still 

retain a significant portion of their biological value, 

particularly for migratory birds. We hope to bring 

more resources and tools to the San Luis Valley to 

complement the ongoing efforts of other organizations 

to maintain and improve the relationship between 

agriculture and wildlife, especially migratory birds 

and endangered species.

The San Luis Valley is a large intermountain 

valley bounded by the San Juan and Sangre de Cristo 

Mountains, whose rain shadows result in high-desert 

conditions. However, the complex hydrology of the valley and the snowmelt runoff from the mountains have 

created a variety of dynamic wetlands and riparian 

corridors on the valley floor, resulting in a diverse assemblage of plants and wildlife. The valley provides 

habitat for many Federal trust species, including the 

southwestern willow flycatcher, western snowy plover, 

numerous species of migrating and nesting waterfowl, 

and 95 percent of the Rocky Mountain population of 

greater sandhill cranes. 

Anthropogenic (human-caused) practices including 

agriculture, changes in fire regime, and climate change 

have resulted in substantial changes to the hydrology 

and historical vegetation of the San Luis Valley. 

The wetlands and fields of the San Luis Valley Conservation Area are an important stopover habitat for migrating 

sandhill cranes, an important tourist draw to the area.

© Joe Zinn
2 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

In this desert environment, the timing and amount 

of water flowing from the adjoining mountains is the 

biggest influence on the environmental and economic 

conditions. The mid- to late-1800s brought extensive 

development of irrigation infrastructure to support 

a growing ranching and farming industry that relied 

on flood-irrigation techniques. This resulted in significant alteration in stream and river hydrology and 

the associated, naturally occurring, wetland habitats. 

However, the introduction of large amounts of irrigation water onto newly established and expanded 

hay meadows and crop fields provided substantial 

areas of habitat for migratory waterbirds that did not 

historically exist. 

As the demand for surface water exceeded the 

supply, technology allowed development of ground 

water sources resulting in continued growth of the 

agriculture industry. By 1900, more than 1,000 irrigation wells had been drilled into the confined aquifer. 

Between 1930 and 1970, 6,000 more wells were drilled 

in both the confined and unconfined aquifers, allowing 

more land to be irrigated. These free-flowing wells are 

from only the confined aquifer and cover less than half 

the irrigated acreage. The amount of land under irrigation has not increased much, if at all, since the 1930s. 

Concerns about effects caused by stream depletions 

prompted the Colorado State Engineer in the early 

1970s to issue a moratorium on new well development 

in the confined aquifer and all tributary wells except 

the Closed Basin. A similar moratorium was issued 

for the Closed Basin in 1981. The 1960s and 1970s saw 

dramatic conversion from flood-irrigation practices to 

the use of center-pivot sprinklers. This new technology 

offered substantial labor- and water-saving efficiencies 

but is of little value to migratory waterbirds except 

for the continued availability of waste grain eaten by 

geese and sandhill cranes.

Due to the hydrologic connection between surface 

and ground water, and the compounding effects brought 

by the chronic drought conditions of 2002 to present, 

wetland basins throughout the San Luis Valley are 

experiencing a very dry period. In 2003, farmers north 

of Alamosa began voluntary efforts to address well 

depletions. In 2004, the Colorado legislature provided 

guidelines for setting up management plans to regulate 

ground water use in the valley to ensure ground water sustainability in a way that does not harm senior 

water users. The State engineer adopted two rules, 

“Groundwater and Irrigation Season Rules for Water 

Division No. 3” and “Confined Aquifer New Use Rules 

for Division 3”, in 2015. Although the task has been 

challenging, the outcome will help the remaining agricultural operations and wetland and riparian habitats.

The San Luis Valley is lucky to have an active 

conservation community of local, State, Federal, and 

national organizations working to protect many of 

the same habitats valuable to migratory birds and 

endangered species. As the cost of agriculture rises, 

so do the economic incentives to sell irrigation water 

rights and convert them to residential, industrial, and 

municipal uses, which increases the challenge of these 

organizations to keep water on the land to produce 

commodities and wildlife habitat.

The SLVCA will conserve a network of vital wildlife 

habitat through voluntary conservation easements and 

a limited amount of fee-title acquisition. The SLVCA 

acquisitions will focus on the protection of wetlands 

and associated uplands in the valley through the use of 

up to 250,000 acres of conservation easements. Up to 

an additional 30,000 acres of fee-title acquisition from 

willing sellers will be used (such as for boundary simplification and surface water rights acquisition) where 

it will benefit the management and objectives of the 

valley’s existing three Alamosa, Baca, and Monte Vista 

National Wildlife Refuges. We will acquire land in fee 

title only when Service objectives could not be accomplished with conservation easements. An overview of 

the project area is provided in figure 1. 

The SLVCA will be the second phase of a larger 

conservation vision for the San Luis Valley that began 

in 2010. While the project was initially envisioned as a 

single broad conservation area, we recognized the need 

for accelerated planning in the southeastern portion of 

the project area, which resulted in the establishment 

of the Sangre de Cristo Conservation Area (SCCA) 

in 2012. The SLVCA encompasses the remainder of 

the original project area.

This document—a land protection plan (LPP)—

sets out the basis, priorities, and general actions for 

the SLVCA. The environmental assessment (EA) in 

appendix A documents the analysis for the LPP that 

was conducted by the Service’s planning team (refer 

to “Appendix B—List of Preparers and Reviewers”). 

The Service found that the SLVCA project would 

have no significant effect on the human environment; 

thus a finding of no significant impact was documented 

in “Appendix C—Environmental Compliance for the 

Land Protection Plan,” where other compliance documents and approvals are also found.

Purpose of the San Luis 

Valley Conservation Area 

The purpose of the SLVCA is to protect Federal 

trust species and other plants and wildlife of the San 

Luis Valley while ensuring the long-term function and 

resilience of its diverse ecosystems. Acquisition and 

administration of the SLVCA will focus on protecting 

the land and water supporting the riparian areas, wetlands, and key uplands that complement and connect 

existing protected areas. This purpose is in alignment 

with, but does not supersede, the vision and statutory 
Chapter 1—Introduction and Project Description 3Figure 1. Overview map of the general land cover of the San Luis Valley Conservation Area in Colorado and New Mexico.
4 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

purposes of the three existing refuges within the San 

Luis Valley National Wildlife Refuge Complex or the 

SCCA, as described below.

The San Luis Valley Conservation Area contains a rich 

mosaic of working ranch lands and important wildlife 

habitat.

USFWS

VISION FOR THE SAN LUIS VALLEY NATIONAL 

WILDLIFE REFUGE COMPLEX

The San Luis Valley National Wildlife Refuge 

Complex, set in a high expansive desert valley, 

is cradled between the snowcapped peaks of the 

San Juan and Sangre de Cristo Ranges. Mountain snowmelt feeds the Rio Grande, numerous 

streams, and a dynamic ground water system, 

creating a diverse mix of playas, wet meadows, 

and willow and cottonwood riparian corridors that are in stark contrast with the surrounding arid landscape. As reflected by 

12,000 years of human history in the valley, 

the San Luis Valley National Wildlife Refuge 

Complex attracts many people. Visitors experience the ancient song of the sandhill crane, witness evening flights of thousands of waterfowl, 

and listen to bugling elk. Through ever changing conditions like climate change, the refuges 

support and foster a collaborative spirit between 

their neighbors and partners to conserve the 

valley’s treasured resources.

PURPOSE OF THE ALAMOSA AND MONTE VISTA 

NATIONAL WILDLIFE REFUGES

The Alamosa and Monte Vista National Wildlife 

Refuges were established under the authority of the 

Migratory Bird Conservation Act “for use as inviolate 

sanctuaries, or for any other management purpose, 

for migratory birds.”

PURPOSE OF THE BACA NATIONAL WILDLIFE 

REFUGE

The purpose of the Baca National Wildlife Refuge 

shall be to restore, enhance, and maintain wetland, 

upland, riparian, and other habitats for native wildlife, plant, and fish species in the San Luis Valley. In 

administering the Baca National Wildlife Refuge, the 

Secretary shall, to the maximum extent practicable 

(A) emphasize migratory bird conservation; (B) take 

into consideration the role of the refuge in broader 

landscape conservation efforts; and (C) subject to any 

agreement in existence as of the date of enactment of 

this paragraph, and to the extent consistent with the 

purposes of the refuge, use decreed water rights on 

the refuge in approximately the same manner that the 

water rights have been used historically.

PURPOSE OF THE SANGRE DE CRISTO 

CONSERVATION AREA

The purpose of the SCCA is to protect the highelevation wildlife habitat of the Sangre de Cristo 

Mountains and the uplands of the southeastern San 

Luis Valley, with an emphasis on migratory birds and 

imperiled species. Acquisitions within, and administration of, the SCCA will focus on promoting the 

adaptive capacity and resilience of these ecosystems 

by ensuring connectivity between existing protected 

areas and by protecting wildlife movement corridors, 

particularly riparian areas.

Issues Identified and 

Selected for Analysis

We solicited comments about the SLVCA from the 

public through direct mailings, news releases, public 

meetings, and direct contacts. These comments were 

incorporated into this land protection plan.

■ On March 15, 2011, the Service opened a scoping 

period for the public with the publication of a 

notice of intent in the Federal Register (FR Doc. 

2011–5924). The notice of intent notified the public 

of the Service’s intention to begin the coplanning 

and NEPA review for the CCP and LPP for the 

San Luis Valley National Wildlife Refuge Complex. 
Chapter 1—Introduction and Project Description 5

■ Public scoping meetings were held on March 29, 

2011, in Alamosa, Colorado; March 30, 2011, in 

Monte Vista, Colorado; and March 31, 2011, in 

Moffat, Colorado. The scoping meetings were attended by approximately 50 people, many of whom 

provided input for the scoping process. Additionally, 

14 written comments were received from organizations and members of the public. 

■ A press event and public meeting was held at 

Adams State College in Alamosa, Colorado, on 

January 4, 2012, at which the Secretary of the 

Interior, Ken Salazar, organized the presentation 

of several complementary initiatives for the San 

Luis Valley and Sangre de Cristo Mountains. One 

of these initiatives was landscape scale conservation, which Dan Ashe, the Director of the Service, 

presented as being embodied by the SLVCA. 

Questions were answered and comments taken 

at a breakout session following the main meeting.

■ The project’s planning Web site (www.fws.gov

/alamosa/planning/lpp/co/slv/slv.html) was established in early March of 2011. The site provides 

information about meetings and downloadable 

versions of public documents. Individuals can also 

sign up to be on the project mailing list through 

the Web site.

During scoping, the CCP and LPP were still being 

planned simultaneously. However, the two plans have 

since been separated and the LPP process has been 

moved up to take advantage of conservation opportunities that may not exist in the future. As such, 

many of the issues identified during scoping are not 

specific or relevant to the LPP. The applicable issues 

and questions identified during the scoping process 

and during internal conversations among the SLVCA 

planning team follow:

■ The SLVCA must protect the wildlife habitat, specifically wetlands, riparian corridors, grasslands, 

and shrublands, of the San Luis Valley, while also 

supporting the rural agricultural qualities that 

define the region.

■ What role can the conservation area play in protecting listed species and species of concern?

■ How will the SLVCA affect water use in the valley?

■ The SLVCA should not negatively affect private 

property rights in the valley.

■ The Service needs to build on existing partnerships 

for land protection.

■ How will the public be able to use lands protected 

under the SLVCA?

■ The Service needs to make sure that the SLVCA 

planning process incorporates the importance of 

protecting cultural resources.

■ How will the SLVCA increase the capacity to 

adapt to climate change on the existing refuges and 

habitat throughout the valley?

■ How will the SLVCA protect the water resources 

of the San Luis Valley from efforts to move water 

to other areas of the State or elsewhere?

■ The plan should account for air, soil, sound, and 

visibility effects. 

Public Review of and 

Comments on the Draft EA 

and LPP

This final LPP is based on the draft EA and LPP 

for the SLVCA, which the Service released for comment on May 9, 2012 for a 30-day public review period. 

The draft documents were made available to the public 

via the project Web site, as well as to Federal officials 

and agencies, State officials and agencies, 17 Native 

American tribes with aboriginal interests, and members 

of the public who had asked to be added to the project 

mailing list. In addition, three public meetings were 

held in Alamosa, San Luis, and Moffat, Colorado on 

May 14, 15, and 16, 2012, respectively. Approximately 

50 members of the public attended these three meetings. In addition to several comments voiced at these 

public meetings, the Service received eight written 

comments from government agencies and nongovernmental organizations and corporations, and six written 

comments from individuals. Comments were reviewed 

and incorporated into the administrative record. 

The substantive comments were published with 

Service responses in appendix D of the final LPP for 

the SCCA, which was published in August 2012. Refer 

to the online document at http://www.fws.gov/mountain-prairie/refuges/lpp_PDFs/sdc_lpp_appendix.pdf.

Of those comments that showed a clear opinion in 

favor or opposed to the project, 75 percent were supportive in nature. The comments generally in favor 

of the SLVCA mention items such as the following:

■ The SLVCA is entirely a willing-seller program, 

not an imposition.

■ The Service has emphasized the collaborative nature 

of the project. The SLVCA is one of many conservation initiatives.

■ The plan was comprehensive.
6 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

■ The Service’s conservation goals are complementary 

with those of residents in Crestone and Baca Grande 

who would like to see perpetual conservation easements in those municipalities. 

■ The prioritization strategy emphasizes promoting 

capacity for climate change adaptation.

■ Easement language should allow changes in water 

use only if beneficial to wildlife. Similar comments 

argued for a more aggressive stance by the Service 

to restore historical hydrology in the San Luis Valley.

■ An emphasis on sustainability in the San Luis Valley could help bolster its already strong or growing 

nonagricultural sectors such as finance, services, 

and tourism.

■ The land protection strategy is transparent and 

guided by habitat needs for identified trust species.

■ Conservation easements are effective and more 

popular than new Federal land acquisition.

■ There is appreciation of the landscape-scale nature 

of the project.

■ In addition to full-market value, the Service should 

consider bargain sales for easements.

■ There is appreciation for the gradual nature of and 

phased approach to the SLVCA.

■ The Service needs to include more areas of northern New Mexico (Chama Peaks area and Jicarilla 

Apache lands) in the project boundary.

■ In addition to habitat value, the Service should consider other qualities such as historical resources, 

open space, and public access.

■ The easement program should accommodate small 

parcels, such as the vara strips associated with 

acequia irrigation practices (community-owned 

water distribution).

■ The program will protect both wildlife and 

agriculture.

Comments not in support of the project identified 

the following concerns:

■ There have been bad past experiences with easements restricting changes in agricultural operations.

■ The Service should consider impacts of easement 

restrictions on the ability of utility companies to 

promote electrical reliability and renewable energy.

■ Industry was not reached during scoping.

■ There is general dissatisfaction with the impact 

of the Federal Government on land access and 

quality of life.

■ The Rio Grande Water Conservation District is 

concerned about potential competition between the 

Service’s easement program and their attempts to 

acquire land for mitigation for the San Luis Valley 

Habitat Conservation Plan.

The following substantive questions were raised 

that were neither in opposition to nor in support of 

the SLVCA:

■ How will being within the SLVCA boundary influence decisionmaking (for example, grazing permits) 

by other Federal agencies?

■ How will the presence of an easement on an 

adjacent property affect a landowner who chooses 

not to sell an easement?

■ How will the SLVCA’s establishment affect traditional use rights for Hispanos in Costilla County?

National Wildlife Refuge 

System and Authorities

The SLVCA will be part of the National Wildlife 

Refuge System, whose mission is “to administer a 

national network of lands and waters for the conservation, management, and where proper, restoration of 

the fish, wildlife, and plant resources and their habitats 

within the United States for the benefit of present and 

future generations of Americans” (National Wildlife 

Refuge System Improvement Act of 1997). National 

wildlife refuges provide important habitat for native 

plants and many species of mammals, birds, fish, 

insects, amphibians, and reptiles. They also play a vital 

role in conserving threatened and endangered species. 

Refuges offer a wide variety of wildlife-dependent recreational opportunities, and many have visitor centers, 

wildlife trails, and environmental education programs.

Conservation of more wildlife habitat in the SLVCA 

will be consistent with the following policies and management plans:

■ Migratory Bird Treaty Act (1918)

■ Migratory Bird Hunting and Conservation Stamp 

Act (1934)

■ U.S. Fish and Wildlife Act (1956)

■ Bald and Golden Eagle Protection Act (1962)

■ Land and Water Conservation Fund Act (1965)
Chapter 1—Introduction and Project Description 7

■ Endangered Species Act (1973)

■ Migratory Non-Game Birds of Management Concern in the U.S. (2002)

■ Alamosa and Monte Vista National Wildlife Refuge 

Complex Comprehensive Conservation Plan (2003)

■ Baca National Wildlife Refuge Conceptual Management Plan (2005)

The acquisition authorities for the easements and 

property acquisition are the U.S. Fish and Wildlife Act 

of 1956 (16 United States Code [U.S.C.] 742a–j) and the 

National Wildlife Refuge System Administration Act 

of 1966 (16 U.S.C. 668dd–ee), as amended. Land will be 

acquired with the use of the Land and Water Conservation Fund, which is derived primarily from oil and 

gas leases on the Outer Continental Shelf, motorboat 

fuel taxes, and the sale of surplus Federal property. 

As proper, the Service could also buy land interest 

through the use of Federal Duck Stamp revenue from 

the Migratory Bird Hunting and Conservation Stamp 

Act of 1934. There could also be more money to acquire 

lands, water, and interests for fish and wildlife conservation purposes as identified by the U.S. Congress or 

donations from nonprofit organizations. Any acquisition 

from willing sellers will be subject to available money.

Related Actions and 

Activities

The San Luis Valley and surrounding mountains 

contain many public lands and private protected areas, 

some of which are contiguous with other protected 

areas and some of which are isolated. Several existing State, Federal, and private land trust programs 

promote the conservation of habitats in the SLVCA; 

these public lands and their relationship to the SLVCA 

and SCCA are shown in figure 2. 

SAN LUIS VALLEY NATIONAL WILDLIFE REFUGE 

COMPLEX

The San Luis Valley National Wildlife Refuge 

Complex includes three existing refuges and two 

conservation areas: the Alamosa, Baca, and Monte 

Vista National Wildlife Refuges and the SCCA and 

the SLVCA. 

■ The refuges were established for different purposes, as outlined earlier in this chapter, and protect 12,026 acres, 92,500 acres, and 14,800 acres, 

respectively. All three refuges currently contain a 

variety of habitats, with a special emphasis on wetlands and riparian systems. Management practices 

include vegetation manipulation and the artificial 

movement of water. An updated comprehensive 

■ conservation plan for the three refuges was finalized in 2015.

■ The SCCA has an approved acquisition boundary 

of approximately 1 million acres, of which we are 

authorized to acquire up to 250,000 acres of conservation easements; nearly 172,000 acres have been 

conserved through this initiative to date.

■ The SLVCA has an approved acquisition boundary 

of 4.2 million acres within which the Service can 

acquire up to 250,000 acres of conservation easements and 30,000 acres in fee title.

U.S. FISH AND WILDLIFE SERVICE—PARTNERS 

FOR FISH AND WILDLIFE PROGRAM

Since 1990, the Service has been working with private 

landowners in the San Luis Valley to conduct habitat 

improvement projects on private lands. These projects 

are with willing landowners and target the needs of 

trust species, such as migratory birds and imperiled 

species. Projects have focused on restoring wetlands, 

improving riparian habitats, and restoring habitat for 

Rio Grande sucker, chub, and cutthroat trout. 

Agreements with landowners include technical 

and financial assistance for restoration practices in 

exchange for habitat assurance with a 10-year agreement for maintenance and management. Since the 

program has been active in the San Luis Valley, 285 

agreements have been established to improve habitat 

on 16,680 acres of wetlands and riparian areas; 12,720 

acres of uplands, and 98 river miles. An objective of 

the SLVCA is to continue working with the same 

landowners and use conservation easements to permanently protect the habitat improvements they have 

made to their property through the Partners for Fish 

and Wildlife Program.

USDA FOREST SERVICE 

The Rio Grande, San Isabel, and Carson National 

Forests border the SLVCA to the north, east, and 

south. These forests contain nearly 4.5 million acres 

of public lands in the Sangre de Cristo, Saguache, and 

San Juan Mountains. The forests contain habitat ranging from pinyon-juniper savanna in the lower areas 

up to alpine tundra and scree fields at elevations more 

than 14,000 feet. Much of this is designated wilderness. These national forests are important habitat for 

Federal trust species, including Canada lynx and Rio 

Grande cutthroat trout, and for unlisted but climate 

change–imperiled species, such as American pika and 

white-tailed ptarmigan. 

BUREAU OF LAND MANAGEMENT 

Much of the land between the national forest boundaries and the largely private valley floor is administered by the Bureau of Land Management (BLM) as 
8 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 2. Map of the San Luis Valley Conservation Area which will be part of a broader network of public and 

private conservation lands in Colorado and New Mexico.
Chapter 1—Introduction and Project Description 9

the San Luis Resource Area. The BLM is actively 

working to restore the historical playa wetlands in 

the South San Luis Lakes and Blanca Wetlands areas, 

the latter of which has been designated as an Area of 

Critical Environmental Concern. These intermittent 

wetlands are particularly important for migratory 

shorebirds, some of which nest in the valley, and are 

also a priority habitat for the Service. The BLM also 

manages the 242,455-acre Rio Grande del Norte National Monument, which overlaps the southern tip of 

the project area in northern New Mexico. Rio Grande 

del Norte National Monument was established in 2013 

by the President of the United States to protect the 

scientific and historical resources of the Rio Grande 

Gorge and surrounding landscape.

NATIONAL PARK SERVICE 

Within the SLVCA boundary is the Great Sand 

Dunes National Park and Preserve. Together, these 

comanaged National Park Service units protect approximately 150,000 acres, from valley floor rabbitbrush 

scrub and the tallest sand dunes in North America to 

peaks more than 13,000 feet in the Sangre de Cristo 

Mountains. 

NATURAL RESOURCES CONSERVATION SERVICE

The Natural Resources Conservation Service 

(NRCS) actively works in the San Luis Valley through 

its Wetlands Reserve Program, a voluntary easement 

program offering landowners the opportunity to protect, restore, and enhance wetlands on their property. 

They do not own land in fee title, but rather provide 

technical and financial support to help landowners 

with wetlands restoration efforts.

STATE OF COLORADO

The State of Colorado owns thousands of acres 

throughout the region and administers State Wildlife Areas and State Habitat Areas on many private 

lands. There are several school sections, managed by 

the State Land Board to provide revenue for K–12 

education in the State. Some of these State Land 

Board parcels, such as La Jara Reservoir, allow recreational use as part of the Public Access program 

with Colorado Parks and Wildlife. There are a handful of regionally important wetlands and riparian 

corridors managed as state wildlife areas, including 

Russel Lakes; San Luis Lakes; and Rio Grande, Higel, 

and Hot Creek State Wildlife Areas. South of Baca 

National Wildlife Refuge and west of Great Sand Dunes 

National Park and Preserve is San Luis Lakes State 

Park, which provides important habitat for migratory 

birds as well as opportunities for wildlife-dependent 

recreation and watersports.

In addition, the State of Colorado has made significant investments in land conservation in the SLVCA 

through the additional programs of Great Outdoors 

Colorado, Colorado Parks and Wildlife, and Colorado 

Water Conservation Board.

LAND TRUSTS

Tens of thousands of acres are protected in either 

fee title and easement programs paid for, or administered by, several conservation and land trust organizations, including but not limited to the Wetlands 

America Trust, The Nature Conservancy, the Rocky 

Mountain Elk Foundation, the Colorado Open Lands, 

the American Farmland Trust, Ducks Unlimited, the 

Rio Grande Headwaters Land Trust, and the Colorado 

Cattleman’s Agricultural Land Trust. These accomplishments were made possible by substantial funding 

from State, private, and other Federal sources. These 

organizations have many different objectives; some 

focus on the preservation of undeveloped agricultural 

land to provide resources for the future, some are 

interested in protecting specific wildlife resources such 

as wetlands, and some have cultural or recreational 

objectives. The efforts of each of these organizations complement each other as well as efforts being 

undertaken by public agencies, including the Service. 

The locations of easements on private land are largely 

confidential, but there are some important land trust 

properties held in fee title as well, such as The Nature 

Conservancy’s Medano-Zapata Ranch, which borders Baca National Wildlife Refuge and Great Sand 

Dunes National Park and Preserve. This property is 

a 103,000-acre working ranch and is home to a herd of 

2,500 bison that are managed to mimic natural grazing 

patterns in the high desert shrub and grasslands.

Habitat Protection and the 

Easement Acquisition Process

Habitat protection will occur through the purchase 

of conservation easements and limited fee-title lands 

when necessary to further the management of existing 

refuges. It is the Service’s long-established policy to 

acquire the minimum interest in land from willing 

sellers to achieve habitat protection goals, and conservation easements are an effective tool for achieving 

these goals.

The acquisition authority for the SLVCA is the U.S. 

Fish and Wildlife Act of 1956 (16 U.S.C. 742a–j). The 

Federal money used to acquire conservation easements 

will largely come from the Land and Water Conservation Fund, which is derived from oil and gas leases on 

the Outer Continental Shelf, motorboat fuel tax revenues, and the sale of surplus Federal property. There 

could be more money to acquire interests in habitat 

and water through direct congressional appropriations, 

donations, and the Federal Land Transaction Facilitation Act if the U.S. Congress votes to reauthorize it.
10 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Conservation Easements and 

Other Acquisitions

An easement is a conservation tool that has been 

extensively employed in the SLVCA project area and 

throughout the larger region by other organizations. 

Easements involve the acquisition of certain rights to 

the property, such the right to subdivide or develop 

certain types of new infrastructure, while leaving the 

land title in the hands of the private property owner. 

Easements tend to be a cost-effective and socially 

acceptable means of habitat conservation. Many of 

the current agricultural land use practices are consistent with wildlife resource protection, and the use 

of easements will help ensure a strong and vibrant 

rural lifestyle.

There may be circumstances in which management 

objectives cannot be achieved, such as small boundary 

adjustments to existing refuges. In these cases, the 

Service will consider the limited use of fee-title acquisition, not to exceed 30,000 acres, as was described 

in the preliminary project proposal for the SLVCA.
Chapter 2—Area Description 

and Resources

This chapter describes the biological, cultural, and 

socioeconomic resources of the SLVCA that could be 

affected by its establishment. The SLVCA consists 

of approximately 4 million acres within the Southern 

Rockies and the Arizona and New Mexico Plateau 

ecoregions (U.S. Environmental Protection Agency 

2011). The project encompasses all or most of Alamosa, 

Conejos, Hinsdale, Mineral, Rio Grande, and Saguache 

Counties in Colorado, as well as a portion of northern 

Rio Arriba and Taos Counties, New Mexico. About 

half of the project area is publicly owned. 

Because of the nearly 7,000 feet in elevation change 

across the project area, the SLVCA contains a diverse 

array of plant communities, ranging from rabbitbrush 

scrub and sagebrush on the valley floor to alpine tundra and scree fields on the peaks of the surrounding 

mountains. As described in detail in this chapter, the 

habitats of the valley and surrounding mountains are 

crucial to the breeding and migration of migratory birds, 

and provide important opportunities for persistence 

or reintroduction of populations of imperiled species 

that are protected under the Endangered Species Act.

Physical Environment

The physical environment of the conservation area 

is described below in terms of its geology, minerals, 

water, hydrology, and climate.

GEOLOGY

The San Luis Valley is part of the much larger Rio 

Grande Rift Zone that extends from southern New 

Mexico northward through the San Luis and Upper 

Arkansas valleys to its northern termination near 

Leadville, Colorado (McCalpin 1996). The San Luis 

Valley is bordered on the east by the linear Sangre 

de Cristo Mountains, which were created by extensive block faulting during the Laramide Orogeny. The 

north-northwest part of the valley is bordered by the 

southernmost reach of the Sawatch Mountains. The 

west side of the valley is flanked by the San Juan 

Mountains, the result of extensive Tertiary-aged 

volcanism. In sharp contrast to the steeply rising 

mountains on the eastern side of the valley floor, the 

Oligocene volcanic rocks of the San Juan Mountains 

dip gently eastward into the valley floor, where they 

are interbedded with valley-fill deposits. Valley-fill 

Dozens of species of migratory waterbirds forage or nest 

in seasonal and temporary wetlands.

© Joe Zinn

deposits consist of sedimentary rocks that interfinger 

with volcanic deposits. Quaternary deposits include 

alluvium, sand dunes, and pediments along the mountain fronts (USFWS 2011). 

MINERALS

Sand and gravel are the major mineral commodities that are mined near the San Luis Valley. Rock, 

sand, and gravel mines are scattered throughout the 

valley, but are concentrated around the cities of Alamosa and Monte Vista and the town of Del Norte, 

Colorado. No coal mining permits are active in the 

SLVCA (Colorado Division of Reclamation, Mining, 
12 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

and Safety 2012). Other minerals that are mined in the 

area include gold, silver, peat, and limestone. There 

is also nascent oil and gas exploration in the valley 

(USFWS 2011). 

WATER AND HYDROLOGY

The SLVCA contains the upper headwaters of the 

Rio Grande watershed (figure 3). Because of its position in a high-mountain desert, the valley floor receives 

little precipitation, and most surface and ground water 

is a result of runoff from the surrounding mountains. 

There are numerous perennial and intermittent drainages that descend from the Sangre de Cristo and 

San Juan Mountains. Some of the larger waterways 

include the Alamosa, Conejos, Rio Grande, and San 

Antonio Rivers. 

A portion of the northern valley, known as the Closed 

Basin (a sump) does not directly contribute water to 

the Rio Grande. The Closed Basin may have formed 

in the middle Pleistocene when the lake that filled the 

valley began to dry up, resulting in an environment of 

swamps and organic-rich sediments. Mayo et al. (2006, 

as cited in USFWS 2011) refer to the Closed Basin of 

Pleistocene time as the “ancestral sump.” Currently, 

the Closed Basin covers approximately 2,940 square 

miles in the northern part of the valley and is separated from the rest of the valley by a low alluvial fan. 

The Closed Basin is composed of the drainage basins 

of several small but important waterways, including 

but not limited to Carnero, Cottonwood, Crestone, 

La Garita, Medano, Saguache, San Luis, Spanish, and 

Willow Creeks. Water enters the Closed Basin through 

precipitation and snowmelt from the 4,700 square miles 

of watershed in the surrounding mountains and substantial inflow of water diverted from several ditches 

off the Rio Grande, including the Farmer’s Union Canal, 

Rio Grande Canal, and others. Water exits primarily 

through evapotranspiration and through exports from 

the U.S. Bureau of Reclamation’s Closed Basin Project (USFWS 2011). The Closed Basin Project extracts 

ground water from the unconfined aquifer in the sump. 

This water is carried in the Closed Basin conveyance 

channel, which starts in the central part of the basin, 

passes through the Baca Refuge, and delivers water 

to the Rio Grande on the Alamosa Refuge. Water from 

the Closed Basin Project helps Colorado meet its interstate compact obligations with New Mexico and 

Texas (USFWS 2012a). The Bureau of Reclamation 

closely monitors changes in the water table caused by 

the Closed Basin Project and continually adjusts the 

location and volume of pumping to ensure operations 

are within the project’s authorizing guidelines. The 

effects of other pumping in the sump and the chronic 

lack of runoff and aquifer recharge have required the 

Bureau of Reclamation to carefully assess its monitoring data to distinguish these effects from other factors.

The rest of the project area is in the San Luis Valley 

portion of the Rio Grande aquifer system. The San 

Luis Valley is the northernmost portion of a system 

of discrete and separate aquifers that stretches from 

Saguache County, Colorado, to western Texas (Robson 

and Banta 1995). The thick basin-fill deposits in the 

San Luis Valley consist of interbedded clay, silt, sand, 

gravel, and volcanic rock. These form many separate 

aquifer systems, which are generally grouped into two 

major aquifers—a shallow unconfined aquifer and a 

deep confined aquifer—although the lines between 

these features are not absolute. The unconfined aquifer is separated, but not totally disconnected, from 

the confined aquifer by clay layers and lava flows. 

The unconfined aquifer is recharged through infiltration of precipitation, irrigation water, runoff, and 

upward seepage of ground water from the confining bed. 

Discharge from the unconfined aquifer is from ground 

water withdrawals, ground water flow to the south, 

discharge to streams or drains, and evapotranspiration. Water levels in the unconfined aquifer respond 

to local climatic events and fall or rise with the availability of precipitation. Wells drilled into the deep 

confined aquifer are artesian and are buffered from 

climatic conditions. The confined aquifer is recharged 

from precipitation and snowmelt in the high San 

Juan Mountains and the Sangre de Cristo Mountains. 

Discharge from the confined aquifer is principally 

from ground water withdrawals and upward leakage 

through the confining bed (USFWS 2012b).

Alamosa, Baca, and Monte Vista National Wildlife 

Refuges all depend on extensive ground and surface water rights, acquired with respective property 

acquisitions to provide wetland and wildlife habitat. 

The beneficial uses of all surface rights on the three 

refuges are decreed by the State of Colorado as 

“irrigation” and must be used to grow wetland plants 

within legal criteria. The seniority of surface water 

rights on the three refuges range from junior rights, 

with recent appropriation dates, to senior rights appropriated in the late 1800s. 

Surface water use on the refuges varies widely 

between years, depending on availability, and averages 20,795 acre-feet per year and 6,875 acre-feet 

per year on the Alamosa and Monte Vista Refuges, 

respectively. Surface water use on the Baca Refuge 

is poorly documented due to the historical lack of 

instrumentation. Measurement devices were installed 

on streams flowing onto the Baca Refuge in 2013 and 

will provide important data over time. 

Flowing at approximately 2,800 gallons per minute, 

the Mumm Well on the Alamosa Refuge is the largest 

unconfined aquifer well in the San Luis Valley. The 

decree for this well limits diversions to 1,540 acre-feet 

per year. Water from this well represents the vast 

majority of ground water use on the Alamosa Refuge.
Chapter 2—Area Description and Resources 13

Figure 3. Map of the San Luis Valley and Sangre de Cristo Conservation Areas, Colorado and New Mexico, which 

capture the upper headwaters of the Rio Grande, the fourth longest river in the United States.
14 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

The Monte Vista Refuge uses significant quantities of ground water to meet wildlife management 

objectives. Although there is substantial variation 

between years, ground water use on the refuge averages 

approximately 8,122 acre-feet per year.

The U.S. Fish and Wildlife Service is a major user 

of both ground and surface water in the San Luis 

Valley. Federal law requires each Federal agency to 

participate in the water adjudication process of the 

associated State. 

CLIMATE

The climate of the San Luis Valley is consistent 

with its high mountain desert setting, with substantial 24-hour temperature swings because of cold air 

drainage from the surrounding mountains. This cold 

air also creates winter overnight temperatures that 

are often much lower than at many other places at 

similar elevations and latitudes. The mid-January high 

averages 34 °F while the low averages –2 °F, and the 

mid-July high averages 83 °F while the low averages 

37 °F. The montane and alpine parts of the SLVCA 

have much cooler weather because of their 10,000- to 

14,000-foot elevations.

Precipitation in the valley is strongly influenced 

by the surrounding mountains. The windward side of 

the mountain ranges, particularly the San Juan Mountains, receives a substantial amount of orographic 

precipitation, which is caused when air masses rise 

and subsequently cool, dumping their precipitation 

at higher elevations. This results in a marked rain 

shadow effect on the lee side of the mountains, with 

annual precipitation in Alamosa averaging 7.25 inches 

per year (National Weather Service 2012). 

Biological Environment

Plant communities in the San Luis Valley form 

a variety of vegetated habitats—wetlands, riparian 

areas, and uplands—used by wildlife in the area. Refer 

to appendix D for a complete list of plant and animal 

species in the SLVCA.

PLANT COMMUNITIES

The vegetation across the project area varies 

greatly, depending on hydrology, slope, aspect, and 

elevation. The San Luis Valley’s hydrology is strongly 

influenced by surface runoff and ground water flows 

from the surrounding mountains. These conditions 

have created a network of riparian corridors and wetlands that break up large expanses of associated desert and upland habitats across a 7,000-foot elevation 

gradient, resulting in high plant diversity. The broader 

San Luis Valley ecosystem contains 1,132 species of 

The riparian corridors of the San Luis Valley serve as wildlife corridors and provide nesting habitat for the endangered 

southwestern willow flycatcher.

© Joe Zinn
Chapter 2—Area Description and Resources 15

plants (appendix D; Colorado State University Herbarium 2012), which is more than a third of the total 

plant species present in Colorado. 

Wetlands

Wetlands in the conservation area are wet meadows, 

seasonal wetlands, and semipermanent wetlands. 

Irrigation practices on private and public lands support most of these wetlands. 

Wet Meadows. Wet meadow habitat is naturally 

present in the San Luis Valley in both areas that have 

shallow water tables and areas that are periodically 

shallowly inundated early in the growing season. Wet 

meadows are the most widespread wetland type in the 

San Luis Valley. Dominant plants include Baltic rush, 

hair grass, and sedges. Most of the naturally occurring wet meadows have been modified by changes in 

water use, but in some areas this has resulted in an 

expansion of wet meadow areas because of artificial 

irrigation for hay fields and cattle grazing. These agricultural uses create habitat for a variety of wildlife 

(USFWS 2005).

The combination of plant structure and density 

coupled with water depth and duration creates rich 

habitat diversity within each larger area of wet meadow. 

This richness of habitat creates tremendous foraging 

and nesting opportunities for a variety of bird species. 

Among these are many species of ducks and geese as 

well as sora, Virginia rail, white-faced ibis, American 

avocet, Wilson’s snipe, and Wilson’s phalarope. Wet 

meadows provide critical roosting and foraging areas 

for the Rocky Mountain population of greater sandhill cranes, which migrate through the valley in the 

spring and fall. Wet meadows also provide habitat for a 

variety of regionally rare or unusual amphibian 

species, such as northern leopard frog and Plains 

spadefoot toad (USFWS 2005). Also present in this 

habitat, particularly in areas of alkali soils, is the 

somewhat rare slender spiderflower, which once had 

a wide range in the southern Rocky Mountains but 

now occurs almost exclusively in the San Luis Valley.

Seasonal and Semipermanent Wetlands. Seasonal and semipermanent wetlands have hydrologic 

regimes that typically allow for the persistence of 

water throughout the growing season. Water in these 

areas is often deeper than 1 foot. Semipermanent 

wetlands may have substantial areas of open water 

with aquatic vegetation beds, and are often fringed 

by tall emergent vegetation. Tall emergent wetlands 

can also be seasonal and are typically dominated by 

bulrush and cattails.

Swimming birds, including grebes, coots, and 

waterfowl, as well as aerial species such as swallows 

and terns, use open-water areas of these wetlands 

for foraging. Emergent vegetation provides breeding habitat for diving and dabbling ducks, Canada 

The semidesert shrublands and sagebrush habitats of the San Luis Valley Conservation Area, while stark in appearance, 

are important habitat for declining bird species such as the sage sparrow and sage thrasher.

© Trinchera Ranch
16 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

The American pika “hays” the alpine grasses as a means 

of surviving the harsh winters above the treeline in the 

surrounding mountains.

Steve Torbit / USFWS

geese, American bitterns, snowy and cattle egrets, 

black-crowned night-herons, white-faced ibis, and 

marsh passerines (songbirds) such as marsh wrens, 

common yellowthroats, and yellow-headed blackbirds. 

Northern harriers and short-eared owls will also nest 

in residual patches of tall emergent vegetation. Tall 

emergent wetlands with a high density of sedges and 

a shallow seasonal water regime host rails and provide 

nesting sites for dabbling ducks.

Floodplains and Playa Wetlands. Botanical studies 

and limited historical accounts indicate floodplain 

depressions and playa wetlands in the Closed Basin 

of the San Luis Valley exhibited dynamic flooding 

regimes and periods of equally dramatic drying. These 

wetlands received water from surface sources including snowmelt and monsoonal rains. During a series of 

wetter years, the result was emergent plant communities, including spikerush, scarlet smartweed, and 

pondweed. During extended dry periods, these same 

wetlands plant communities converted back to desert 

shrub vegetation, such as greasewood, rabbitbrush, 

and saltgrass, during extended periods of low precipitation (Heitmeyer and Aloia, 2013). 

Riparian Habitats

Riparian habitat has trees, shrubs, and other 

streamside vegetation and is associated with intermittent and perennial waterways. This community may 

flood every year. The historical extent on the valley 

floor has been reduced by the diversion of surface 

water and depletions from ground water use. Woody 

riparian habitat is sensitive to excessive grazing and 

browsing from both domestic and wild ungulates, 

which limits regeneration of the dominant willows and 

narrowleaf cottonwood trees. Shrubs that contribute 

to the structural diversity of riparian habitat include 

redosier dogwood and greasewood. These shrublands 

and forests provide important stopover habitat for 

migratory passerines, as well as nesting habitat for 

species such as Lewis’ woodpecker, willow flycatcher, 

and possibly yellow-billed cuckoo. In addition, the 

shade and streambank stabilization provided by riparian vegetation is important in keeping temperature 

and water quality in streams and rivers for species 

such as the endemic Rio Grande cutthroat trout, Rio 

Grande chub, and Rio Grande sucker. 

Upland Vegetation

Upland vegetation in the conservation area ranges 

from semidesert shrublands and grasslands to montane forests and above treeline. 

Semidesert Shrublands and Grasslands. Shrublands are the most common natural vegetation on the 

San Luis Valley floor. Many of the plants within these 

communities are drought resistant and tolerant of high 

soil salinity. These shrublands are characterized by 

an open to moderately dense assemblage of rubber 

rabbitbrush, greasewood, fourwing saltbush, shadscale, 

and winterfat. Also present in these communities are 

yucca, cactus, and various grasses. At slightly higher 

elevations, rabbitbrush shrublands transition to desert 

scrub and shrub-steppe habitats that have a substantial cover of big sagebrush or sand sagebrush and that 

intergrade with the pinyon-juniper woodlands above. 

Grasses in these areas include Indian ricegrass, alkali 

sacaton, western wheat grass, and blue grama.

Bird diversity and density tend to be relatively 

low in semidesert shrublands because of structural 

and floristic simplicity (Wiens and Rotenberry 1981). 

Species common to this habitat include the horned 

lark, mourning dove, western meadowlark, and loggerhead shrike. Upland grassland habitats have the 

potential to support grassland-dependent species such 

as burrowing owl, long-billed curlew, and a variety of 

sparrows. The sagebrush-dominated habitats are also 

home to the declining sage thrasher and the federally 

proposed as endangered Gunnison sage-grouse. 

Montane Forests. Above the semidesert shrubland, 

the vegetation transitions into pinyon-juniper woodland. This open-canopy forest is dominated by pinyon 

pines and junipers, with an understory consisting of 

shrubs and grasses. According to the Colorado Natural Heritage Program, this woodland’s threat status is 

“fair” and its protection status is “poor-fair.” Pinyonjuniper woodland is particularly threatened by the 

spread of invasive grasses that increase its susceptibility to fire (Colorado Natural Heritage Program and 
Chapter 2—Area Description and Resources 17

The Nature Conservancy 2008). Much of the existing 

pinyon-juniper woodland in the San Luis Valley is 

managed by BLM, though there are extensive stands 

on private lands in Costilla County. Pinyon jays are 

obligate nesters in the pinyon-juniper woodlands, and 

although their population is stable in Colorado, they are 

effective indicators of forest health and are therefore 

a priority species for Partners in Flight throughout 

the Intermountain West (Colorado Partners in Flight 

2000). Other pinyon-juniper associated species include 

black-throated gray warbler and juniper titmouse.

As the elevation increases, the forest becomes a 

mixed conifer forest, which is sometimes part aspen, 

and finally becomes a subalpine spruce-fir forest. These 

forests are home to some bird species, including olivesided flycatcher, yellow warbler, and mountain chickadee; they also provide habitat and migration corridors 

for some important large mammals such as elk, black 

bear, and the threatened Canada lynx. 

Above Treeline. The highest elevations in the SLVCA 

are dominated by alpine tundra, scree fields, and bare 

stone, which can have the appearance of being stark 

or even lifeless. Upon closer inspection, however, one 

observes a remarkable diversity of plants adapted to 

this cold and arid environment, including impressive 

displays of summer wildflowers. These plants provide 

the foundation for an ecosystem containing a suite of 

charismatic fauna, many of which are imperiled by 

habitat shifts because of climate change such as the 

American pika. The high elevations are also home to 

State game species such as bighorn sheep. 

WILDLIFE

The diverse mix of wetland, riparian, shrubland, 

forest, and alpine habitats throughout the SLVCA 

provide for the habitat needs of many assemblages 

of reptiles and amphibians, aquatic species, birds, and 

mammals, including several species of special concern. 

Appendix D lists the wildlife species found in the San 

Luis Valley and surrounding mountains.

Amphibians and Reptiles

The San Luis Valley is a cold desert, so it supports 

only a limited number of reptiles and amphibians. The 

large areas of semidesert shrubland and the scattered 

wetlands and riparian areas are home to a handful of 

snakes and lizards as well as the snapping turtle. The 

arid nature of the region restricts amphibians largely 

to wetlands and riparian corridors; these areas provide 

habitat for tiger salamander and seven species of frogs, 

toads, and spadefoot toads. Among the latter group 

is the boreal toad, a high-elevation toad that appears 

to have declined substantially because of infection 

by Batrachochytrium dendrobatadis, a pathogenic 

fungus. This species is State listed as endangered by 

both Colorado and New Mexico (Colorado Parks and 

Wildlife 2012).

The Rio Grande cutthroat trout, once found throughout 

the Rio Grande and Pecos River watersheds, is now found 

only in scattered cold-water, high-elevation streams.

USFWS

Fish and Aquatic Species

The project area contains the headwaters of the 

Rio Grande. The Rio Grande and its tributaries and 

the valley’s marshes are home to several native fish 

as well as a range of introduced species. Most of the 

challenges faced by these aquatic species are due at 

least in part to anthropogenic causes such as competition with exotic species and water diversions. These 

impacts have been magnified by persistent drought 

conditions since the 1990s. In some cases, conservation easements offered by the SLVCA may be used 

to protect land use practices on watersheds that are 

beneficial to water quality and temperature. Easements that tie water use to the land will have neutral 

effects on aquatic species.

The Rio Grande chub is thought to have once been 

the most common fish throughout the Rio Grande drainage and in the San Luis Closed Basin, but it has been 

extirpated from much of its range, including from the 

main stem of the Rio Grande. The Rio Grande chub 

is now found in several small streams in the San Luis 

Valley, including Crestone Creek on Baca National Wildlife Refuge. The Colorado Natural Heritage Program 

considers the Rio Grande chub to be an S1 (critically 

imperiled) species. It is thought to have declined 

because of habitat fragmentation by impoundments 

for diversions, habitat destruction because of poor land 

use practices, and predation by, and competition with, 

introduced fish species (Rees et al. 2005a). 

The Rio Grande sucker once had a historical range 

similar to that of the Rio Grande chub, and faces similar threats. It appears to have been particularly hard 

hit by competition with the introduced white sucker. 

At one point, the Rio Grande sucker was reduced to 

a single population in Hot Creek in Conejos County, 

Colorado, but it has since been discovered in Crestone 

Creek and reintroduced to several more streams. It is 

considered a State endangered fish in Colorado (Rees 

et al. 2005b).
18 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

In historical times, Rio Grande cutthroat trout1

were found in large numbers in the main stem of the 

Rio Grande and its major tributaries, such as the 

Conejos River; one account from the Conejos River 

in 1877 states that “fishing was so successful ... our 

catch amounted to over a hundred pounds by midafternoon,” which the fishermen shipped off to a restaurant 

in Denver (Sanford 1933). Now, the native trout are 

restricted to high-elevation streams descending from 

the San Juan and Sangre de Cristo Mountains. The 

Rio Grande cutthroat trout occupies approximately 

10 percent of its historical range. Threats to the species include competition and hybridization with, and 

predation by, introduced trout; reduction in habitat 

quality because of water diversions and other hydrological changes; and changes in stream temperature 

because of human water use and global climate change. 

Formerly identified as a candidate species under the 

Federal Endangered Species Act, it was recently removed from consideration in late 2014. 

Some 57 species of nonnative fish have been introduced to the San Luis Valley, either as naturalized 

aquarium fish, escaped aquaculture species, or intentionally introduced sport fish. The latter category has 

brook, brown, golden, and rainbow trout; northern pike; 

bluegill; pumpkinseed; yellow bullhead; common carp; 

largemouth and smallmouth bass; blue, channel, and 

flathead catfish; walleye; and yellow perch. Nongame 

species such as American eel, grass carp, Mozambique 

tilapia, white suckers, and even neotropical tetras and 

armored catfish have become naturalized in the Rio 

Grande drainage as well (USGS 2012).

Birds

The diverse range of habitats along the elevational 

and hydrologic gradient of the SLVCA provide habitat 

for at least 274 species of birds. Some of these birds are 

year-round residents, but many migrate through the 

valley on their way to and from wintering and breeding grounds while others come to the valley to breed 

or spend the winter. Among the migratory species 

are neotropical migrants that winter in Central and 

South America and breed in North America. Riparian corridors and forests are particularly important 

to these species. 

Cordilleran flycatchers breed in forested areas of the 

SLVCA, including cottonwood riparian forest. These 

gallery riparian forests are also thought to host a limited number of yellow-billed cuckoos, recently federally listed as threatened. Olive-sided flycatchers breed 

in the coniferous forests of the mountains surrounding the valley. The southwestern willow flycatcher, a 

subspecies of the more widespread willow flycatcher, 

1

76 Federal Register No. 207, Wednesday, October 26, 2011. Endangered 

and Threatened Wildlife and Plants; Review of Native Species That 

Are Candidates for Listing as Endangered or Threatened; Annual 

Notice of Findings on Resubmitted Petitions; Annual Description 

of Progress on Listing Actions. 66403.

The endangered southwestern willow flycatcher nests in 

the willows along the Rio Grande and its tributaries.

C. Suzanne Langbridge / USGS

breeds in shrub riparian and tree riparian with a willow 

understory; the southwestern willow flycatcher is 

federally and State listed as endangered. Examples of 

other neotropical migrants in the SLVCA include two 

species of phoebe, several more flycatchers, western 

tanager, gray catbird, Bullock’s oriole, and many 

species of warblers. 

Passerines are not the only migrants to make use of 

the area. Black-necked stilts and American avocets are 

shorebirds that migrate from winter ranges in Mexico, 

Central America, and South America to breed in the 

wetlands of the San Luis Valley. At least 25 other 

species of shorebirds use these wetlands as either 

stopover or breeding habitat. Six of these shorebirds, 

including the snowy plover, which breeds in the playa 

wetlands of the Closed Basin, are either focal species 

for the Service’s Migratory Bird Program or are the 

Service’s Region 6 Birds of Conservation Concern. 

Given the scarcity of water in high desert and 

mountain environments, it is perhaps not surprising 

that the San Luis Valley is regionally important for 

both resident and migrant waterbirds. The marshes of 

the valley support 27 species of waterfowl. Approximately 30 percent of the cinnamon teal that summer 

in Colorado breed in the valley (Stephanie Jones, 

USFWS Migratory Birds, personal communication 2012). 

The secretive American bittern breeds in the valley, 

and has experienced population declines throughout 

its range, likely because of wetland disturbance. The 

white-faced ibis breeds in wet meadows and makes 

extensive use of natural and agricultural habitats in 

the valley. Nearly the entire Rocky Mountain population of sandhill cranes uses the San Luis Valley as 

migratory stopover habitat, particularly on and around 
Chapter 2—Area Description and Resources 19

the Monte Vista National Wildlife Refuge, where they 

are the focus of an annual crane festival and a draw 

for thousands of tourists every year. Rookeries of 

great blue herons, snowy egrets, and black-crowned 

night-herons are also present. Conservation of wet 

meadow, playa, and emergent wetland habitat is 

crucial for these species. 

The San Luis Valley hosts an array of diurnal raptors and owls throughout the year. Prairie falcons are 

common year-round residents and use uplands extensively for feeding and resting. The trees and snags 

along waterways are nesting sites for great horned 

owls, long-eared owls, red-tailed hawks, American 

kestrels, and Swainson’s hawks (USFWS 2011). 

The latter species is a bird of conservation concern 

in the Service’s Region 6 and is known to be sensitive to habitat fragmentation. Northern harriers and 

short-eared owls nest in wet meadows and emergent 

wetlands. These two species as well as ferruginous 

hawks, rough-legged hawks, golden eagles, and bald 

eagles overwinter in the valley, where they forage 

for small mammals and other prey in riparian areas, 

uplands, and short-emergent wetlands where cover is 

abundant (USFWS 2011). The higher elevation parts 

of the project area are home to the northern goshawk, 

a generalist predator of rodents and birds that inhabits 

the montane forests of the surrounding mountains. It 

is probable that the forested canyons above the valley 

floor provide habitat for the Mexican spotted owl; these 

species are both State (Colorado) and federally listed 

as threatened, although no designated critical habitat 

for the species occurs in the project area. 

The San Luis Valley is also in the eastern corner 

of the sagebrush region of the Intermountain West 

(Pitkin and Quattrini 2010) and, as such, has some 

strongly sagebrush-associated or sagebrush-obligate 

bird species, meaning those species whose life history 

needs cannot be met in other habitats. The Gunnison 

sage-grouse has a small population at the north end 

of the San Luis Valley (D. Reinkensmeyer, personal 

communication with M. Dixon, February 2012). This 

species is now listed as threatened under the Federal 

Endangered Species Act and is a species of special 

concern in Colorado. Gunnison sage-grouse likely had 

much broader distribution than they do now (Schroeder 

et al. 2004). The Colorado Parks and Wildlife identified 

that some of this former range has potential habitat 

for the species (Gunnison Sage-Grouse Rangewide 

Steering Committee 2005). Sage sparrows have similar 

habitat associations, preferring sagebrush-dominated 

habitats with open to closed canopies (Williams et al. 

2011). Sage thrasher is another denizen of the upland 

shrub habitats of the valley, including sagebrush and 

rabbitbrush scrub. It is one of the Service’s migratory 

bird focal species and one of the Service’s Region 6 

species of concern. It is thought that the primary reasons for the decline of Gunnison sage-grouse are the 

loss and fragmentation of sagebrush habitat (OylerMcCance et al. 2001), so this species is likely to benefit 

from the protection of remaining potential habitat that 

the project will provide. Given the overlap in habitat 

needs of sage-grouse and other sagebrush obligates 

(Rowland et al. 2006), species like sage thrasher and 

sage sparrow will likely benefit from conservation of 

sagebrush and steppe habitat as well.

Mammals

The arid uplands, wetlands, and stream and river 

corridors of the SLVCA provide habitat for large game 

species, including pronghorn, elk, and mule deer. The 

higher elevations hold Rocky Mountain bighorn sheep. 

American bison were once an important part of both 

the San Luis Valley ecosystem and the socioeconomic 

system of the Ute and Pueblo peoples; however, the 

last bison were extirpated from the San Luis Valley 

by 1870 (Colville 1995). The Nature Conservancy now 

manages a bison herd on their Medano-Zapata Ranch 

as a means of simulating natural grazing regimes; however, their stated goal is to introduce a free-ranging 

genetically pure bison herd of at least 3,000 animals 

to the valley by 2015 (The Nature Conservancy 2008). 

The mountains surrounding the San Luis Valley provide important habitat for the threatened Canada lynx. 

Steve Torbit / USFWS
20 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

The San Luis Valley and surrounding mountains are home to thousands of elk.

USFWS

The bison and other megafauna provide opportunities for wildlife-dependent recreation, but are not 

without controversy. Perceived overpopulation of elk, in 

particular, is contentious among farmers and ranchers 

in the valley who are concerned about the crop damage 

and competition for forage between elk and cattle. 

Additionally, managers of the Baca and Alamosa Refuges are concerned about the documented effects of 

elk overbrowsing riparian vegetation important to 

migratory birds.

The elk herd on the east side of the valley has been 

estimated to number approximately 5,000 animals (R. 

Rivale, wildlife biologist, Colorado Parks and Wildlife, 

personal communication, cited in USFWS 2005). A 

recent study of elk carrying capacity in the Great Sand 

Dunes ecosystem found that, under current management practices, the carrying capacity of the region 

should be 6,104 elk (Wockner et al. 2010). Development 

of plans for elk management in the valley is ongoing. 

Small mammals in the SLVCA are those typical 

of the greater Southern Rockies ecosystem. Riparian 

areas and marshes provide resources for beaver and 

common muskrat. Forested areas are home to North 

American porcupine and snowshoe hare. Uplands 

contain other rabbits, such as white-tailed jackrabbits 

and mountain cottontails, as well as the Ord’s kangaroo 

rat. In the highest reaches of the project area, primarily above the tree line, are the charismatic American 

pika and the vocal and inquisitive yellow-bellied marmot. The Gunnison’s prairie dog is a species which 

inhabits the valley floor. This species has suffered a 

sharp decline for reasons that include human persecution and outbreaks of plague. Formerly, it was listed 

as a candidate for protection under the Endangered 

Species Act, but was recently removed following a 

genetic reevaluation of its taxonomic status.1

The aforementioned species serve as prey for 

several predator species in the project area. Black 

bear is a generalist omnivore whose flexibility makes 

it common in many habitat types in the valley. The 

coyote is often found hunting small mammals and 

occasionally larger prey throughout the study area. 

Similarly, both mountain lion and bobcat are quite 

catholic in their habitat needs, though the mountain lion 

has much larger home ranges and tends to specialize 

in hunting ungulates, whereas the bobcat is more 

opportunistic. In contrast to those two cats, the State 

endangered and federally threatened Canada lynx 

is largely a specialist predator of snowshoe hare; in 

the SLVCA, lynx is primarily found in the spruce-fir 

forests of the Sangre de Cristo and San Juan Mountains, where its preferred prey are found. 

The grizzly bear once roamed the mountains of the 

area but was extirpated from Colorado in the early 

20th century; the San Luis Valley grizzlies are remembered now as the mascot of Adams State University 

in Alamosa, Colorado. Similarly, the gray wolf historically hunted in the San Luis Valley and surrounding 

mountains, but was extirpated from Colorado by 1945 

(though it is still State and federally listed as endangered in Colorado). A mounting body of research 

shows the potential ecological benefits of natural or 

1

Federal Register 78, No. 220. November 14, 2013. Endangered and 

Threatened Wildlife and Plants; 12-Month Finding on a Petition to 

List the Gunnison’s Prairie Dog as an Endangered or Threatened 

Species. 68660
Chapter 2—Area Description and Resources 21

human-facilitated reintroduction of wolves, particularly on vegetation adversely affected by unnaturally 

high elk browsing (Ripple and Beschta 2012). Neither 

State nor Federal agencies presently plan to reintroduce wolves to the project area.

Finally, the SLVCA is home to nine species of bats. 

All are insectivorous and hunt primarily by capturing 

insects in flight. The hoary bat and silver-haired bat 

are solitary tree-roosting bats that are present during 

the summer and migrate to warmer climates during 

the winter. The presence of mature cottonwood riparian forests likely supports their presence on the valley 

floor. The migratory Mexican free-tailed bat has an 

exceptionally large summer colony of approximately 

100,000 individuals (Freeman and Wunder 1988) in the 

historic Orient Mine in the northern San Luis Valley 

outside the SLVCA, though there are certainly other 

old mines within the project area that may provide 

roosts for smaller colonies. The remaining species are 

either resident or regionally migratory hibernators.

Cultural Resources

On the hottest days it is cool in the shade, and 

on the very coldest days it is comfortable in 

the sunshine.

—Geologist C.E. Siebenthal, describing the San Luis 

Valley in 1910

Humans have inhabited the San Luis Valley and 

surrounding mountains for more than 12,000 years. 

Their uses of the land reflect both the traditions of 

those who moved to the valley and local adaptations. 

The following summary of the prehistory and history 

of the valley provides an overview of some of the major 

themes and events that illustrate the human interaction with the land. There is an abundance of prehistoric 

evidence as well as early historical accounts, records, 

photographs, and local histories for the valley. This 

synopsis provides only a glimpse into the resources 

and information available with an emphasis on environmental references. 

PREHISTORY

The prehistory of the San Luis Valley has four 

stages: Paleo-Indian, Archaic, Late Prehistoric, and 

Protohistoric. 

Paleo-Indian Stage

Current archaeological evidence shows that the 

earliest humans, called the paleo-Indians, migrated to 

the region near the close of the last ice age approximately 12,000 years ago. These people had a highly 

mobile lifestyle that depended on the hunting of large, 

now-extinct mammals, including mammoths and a huge 

ancient bison. The hallmark of most paleo-Indian sites 

are the beautiful but deadly spear points that were 

launched with the aid of a simple yet expertly engineered spear-thrower called an atlatl. These projectile 

points are generally recovered as isolated occurrences 

or in association with animal kills, butchering sites, or 

small temporary camps. Although the timing of this 

stage varies throughout the region and is constantly 

being refined as more data become available, the stage 

generally lasted until about 7,500 years ago.

Information from the Colorado Office of Archaeology and Historic Preservation shows that 62 paleoIndian resources have been identified in the San Luis 

Valley and surrounding mountains. These sites are 

often located near wetlands and along the shorelines 

of ancient lakes, reflecting the use of abundant floral 

and faunal resources available in these locations. Several paleo-Indian sites in the valley and surrounding 

mountains have been excavated, including the high altitude Black Mountain Site (5HN55) located at 10,000 

feet in the San Juan Mountains south of Lake City in 

the SLVCA. This campsite dates from approximately 

10,000 to 7,000 years ago and has yielded a variety of 

stone tools suggesting animal procurement and processing (Jodry 1999a). 

Several paleo-Indian sites on the valley floor have 

been excavated and provide an extensive record of 

the early occupations. Three of these sites, the Cattle 

Guard site (5AL101), the Linger site (5AL91), and the 

Zapata site (5AL90), are located just south of Great 

Sand Dunes National Park and Preserve and represent camps with an abundance of bison bone and associated stone tools (Cassells 1997, Jodry 1999a). The 

Reddin site (5SH77) near the town of Hooper yielded 

nearly 500 paleo-Indian artifacts suggesting a variety 

of activities and uses (Cassells 1997, Jodry 1999a).

Climatic fluctuations during the Holocene Epoch 

(which started about 12,000 years ago and has continued to the present) are often reflected in the archaeological record. Pollen remains, faunal assemblages, 

and geomorphological deposits suggest periods of 

significant and rather abrupt vegetation changes and 

variations in the amount of moisture (Jodry 1999b, 

Martorano 1999a). Bison remains associated with archaeological sites on the southern plains also show 

oscillations in bison numbers in response to climatic 

conditions (Creel et al. 1990). Although more research 

is needed and archaeologists’ ability to recover and 

interpret the prehistoric record is continually improving, these preliminary studies are an intriguing look 

into the evidence for and the consequences of longterm climatic change.

Archaic Stage

There was a gradual but definite shift in the pattern of human use of the region that began about 

7,500 years ago and continued until approximately 

1,500 years ago. The changes were the result of a 
22 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

The San Luis Valley contains archaeological sites extending thousands of years into prehistory.

Meg Van Ness / USFWS

combination of regional climatic fluctuations and an 

increasing population coupled with technological innovation and regional influences. Although the Archaic 

stage is better represented in the archaeological record 

than the preceding paleo-Indian stage, the identification and interpretation of the remains continues to be 

expanded and refined. Evidence of a greater diversity 

of tools and the use of a larger variety of plants and 

animals than during the preceding paleo-Indian stage 

is found on many sites. 

There have been 618 Archaic stage resources recorded in the Colorado part of the study area. As with 

the earlier inhabitants, the Archaic peoples made 

extensive use of the valley’s wetland resources and 

occupied the rock shelters and several high-altitude 

locations found in the surrounding mountains. Speaking of Archaic sites in the northeastern part of the 

valley, Hoefer states: “Most of the Closed Basin archaeological sites are open camps containing debitage 

and fire-cracked rock scatters, approximately half 

of which contain ground stone implements such as 

metate fragments or manos. Many of these sites are 

located around seasonal wetland marshes and lakes” 

(Hoefer 1999).

The use of the atlatl with spear points continued and 

basketry, cloth, and cordage came into use. Although 

still mobile, the population increasingly made shortterm use of small groupings of structures with storage features. Former hunting blinds and other rock 

structures are fairly common but often difficult to interpret. Archaic Stage rock art is scattered throughout 

the region and the influences of surrounding regions, 

particularly the Plains and the Great Basin, are identifiable at several sites.

Late Prehistoric Stage

Beginning approximately 1,500 years ago, several 

innovations greatly influenced life in the valley (Martorano 1999b). Although these changes were adopted 

at different rates and degrees throughout the area, 

the advent of pottery and the bow and arrow coupled 

with a larger and more sedentary population defines 

the period until approximately 600 years ago. Early 

archaeological research in the valley identified many 

regional influences, with several sites exhibiting 

pueblo-inspired attributes (Renaud 1942). In 1694, 

Don Diego de Vargas documented his visit to the valley, thus providing an early historical written account 

and ushering in the historical period.
Chapter 2—Area Description and Resources 23

The 442 Late Prehistoric resources in the Office of 

Archaeology and Historic Preservation database are 

listed under a variety of designations for this stage, 

but all date to about the same time period. The distribution of Late Prehistoric sites in the valley reinforces 

the trend of intensive use of wetland habitats (Martorano 1999b). This is not surprising as the available 

resources, both floral and faunal, would have continued to be abundant in these areas. Site types include 

camps, stone tool scatters, rock art, rock alignments 

and enclosures, and quarries where the lithic material 

for stone tools was collected.

Protohistoric Stage

By the late 1600s, Spanish incursions into the valley were beginning to affect the lives of the native 

populations. The Utes, who, based on archaeological 

evidence, came to the valley sometime after A.D. 1100 

(Reed 1994) and were the most prevalent occupants 

of the valley, quickly acquired horses and other trade 

items. Although many other Native American groups 

probably visited or traveled through the valley, the 

Comanche, Apache, Navajo, Arapaho, Cheyenne, and 

several northern Pueblos also had a significant if not 

sustained presence (Martorano 1999c).

The 59 recorded Office of Archaeology and Historic 

Preservation sites from this stage include the traditional stone tools and ceramics mixed with used or 

flaked glass, trade beads, and metal projectile points. 

Wickiups (conical timbered structures) and trees with 

peeled bark (indicating the harvesting of the edible 

cambium layer) were common, as is rock art with motifs and depictions of postcontact goods. 

EARLY HISTORY

The historical period for the valley began with the 

reoccurring contact of the native peoples with people 

of European decent and ended in the mid-twentieth 

century. This interaction generally followed many 

years of occasional contact, often for the exchange of 

trade goods. The narrative below briefly summarizes 

some of the major historical influences, patterns, and 

themes in the region.

Early Exploration and Trade

I take and seize one, two, and three times, 

one, two, and three times, one, two, and three 

times, and all those which I can and ought, the 

Royal tenancy and possession, actual, civil, 

and criminal, at this aforesaid River of the 

North, without excepting anything and without any limitation, with the meadows, glens, 

and their pastures and watering places. And 

I take this aforesaid possession, and I seize 

upon it, in the voice and name of the other 

lands, towns, cities, villas, castles, and strong 

houses and dwellings, which are now founded 

in the said kingdoms and provinces of New 

Mexico, and those neighboring to them, and 

shall in future time be founded in them, with 

their mountains, glens, watering places, and 

all its Indian natives ....

—Capitán Gaspar Pérez de Villagrá in La Historia de la 

Nuevo Mexico, 1610

With these bold words in 1598, Spain claimed all 

lands, structures, and people along the Rio Grande—

including the San Luis Valley—forever. This followed 

several years of sporadic Spanish incursions into 

northern New Mexico and southern Colorado, which 

ushered in several decades of trade, conflict, and 

settlement. Many Spanish traveled along the North 

Branch of the Spanish Trail, which had both western 

and eastern routes through the valley. Although the 

Spanish relinquished ownership of the valley in 1821, 

their influence survives as a vital part of the landscape 

and people today.

There are many explorers and settlers who left a 

legacy of journals, maps, and other accounts of their 

time in the San Luis Valley. These documents offer 

a wide variety of historical and environmental information. The examples summarized below provide 

a glimpse into the types of information and insight 

available in these early accounts. 

Don Diego de Vargas, 1694. The 1694 journal of Don 

Diego de Vargas survives as the earliest written account of the San Luis Valley. The journal is a wealth of 

information about the native peoples, topography, and 

environment (Colville 1995). After leaving Santa Fe, 

De Vargas followed the North Branch of the Spanish 

Trail northward, traveling east of the Rio Grande, and 

entering the valley just southeast of Ute Mountain. 

From there he continued north, crossing what would 

become the New Mexico and Colorado State line and 

paralleling the western side of San Pedro Mesa before 

heading west along Culebra Creek. When he reached 

the Rio Grande, he turned south and crossed the river 

about five miles south of the confluence. His return trip 

to Santa Fe took him along the Rio San Antonito on 

the west side of the Rio Grande, exiting the valley on 

the west side of San Antonio Mountain (Colville 1995). 

His six days in the valley included contact, trade, 

and occasional skirmishes with the Utes and confrontations with Taos Puebloans. He also documented 

large herds of bison and some “very large deer.” This 

reference is the earliest known historical account of 

bison in the valley (Colville 1995), the last being a 

brief mention of bison by Juan Bautista Silva along 

the Rio San Antonio south of present-day Antonito in 

the spring of 1859 (Kessler 1998). During de Vargas’s 

travels, the use of sign language and smoke signals 

for communication is well documented, as is the need 

to be near water during midsummer.
24 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Notable features of the de Vargas journal include 

the advantageous yet temporary alliance of de Vargas’s 

men with the Utes and Apaches to combat a mutual 

enemy: the Comanche. As he traveled along the west 

side of the valley, de Vargas refers to the San Juan 

Mountains by their early Spanish name: Sierra de la 

Grulla, or Mountains of the Cranes. And, in an interesting meteorological observation, de Vargas states 

on August 24 that, “From the beginning of the march 

we suffered from bitter cold”—this during a month 

that now has an average daytime high temperature 

in the upper 70s.

Juan Bautista de Anza, 1779. Eighty-five years 

later in 1779, Juan Bautista de Anza, the Governor and 

Military Commander of New Mexico, left Santa Fe and 

headed north to quell the Comanche raids that were 

devastating Spanish settlements in the region. Traveling 

by night to avoid detection, de Anza followed the 

North Branch of the Spanish Trail along the eastern 

foothills of the San Juan Mountains, crossed Poncha 

Pass, and then headed east to the plains near Pikes 

Peak. From there he headed south along the foothills, through the areas that would become Colorado 

Springs and Pueblo, where he fought several victorious battles with the Comanche. He concluded his 

campaign by crossing back into the valley at Sangre 

de Cristo Pass (which is also known as La Veta Pass) 

and taking the eastern route of the North Branch of 

the Spanish trail back to Santa Fe (Kessler 1998). He 

initially entered the valley on August 19, 1779, and by 

September 4 of that year he had reentered the valley 

near Fort Garland on his return trip to Santa Fe. 

Zebulon Montgomery Pike, 1807. Unlike the earlier 

Spanish explorers, Captain Zebulon Montgomery Pike 

entered the San Luis Valley from the east, having 

traveled west from St. Louis across Missouri, Kansas, 

and the plains of Colorado. Pike’s mission was to map 

and describe the southern parts of the newly acquired 

Louisiana Purchase. On January 27, 1807, he and most 

of his men (except five that were left along the trail 

because they were unable to walk on their frozen feet) 

crossed the Sangre de Cristo Mountains and entered 

the valley near the Great Sand Dunes (Carter 1978, 

Hart and Hulbert 2006, Ubbelohde et al. 2001). Pike 

built a simple stockade near where the current town 

of Sanford is located and stayed there until February 26, when Spanish officials took him prisoner and 

escorted him down to Santa Fe because “it was necessary his Excellency should receive an explanation 

of my business on his frontier ....” (Zebulon Pike, 

Thursday, February 26, 1807).

Although Pike’s journal in the days preceding the 

ascent into the valley often mentions seeing “a gang of 

buffalo,” including in the Wet Valley, there is no mention of buffalo after he enters the San Luis Valley. In 

contrast, deer are often mentioned in the valley and 

goose was a part of at least one meal. Pike grew fond 

of the valley and concluded that “it was at the same 

time one of the most sublime and beautiful prospects 

ever presented to the eyes of man” (Zebulon Pike, 

Thursday, February 5, 1807).

Jacob Fowler, 1821 to 1822. The journal of Jacob 

Fowler, which dates from 1821 to 1822 and which The 

New York Times referred to as “quaint and interesting” 

(The New York Times 1898), is a wealth of information 

about the environment and the interactions between 

the various peoples who occupied the valley (Coues 

1965). The New York Times further describes the 

journal, just published by noted ornithologist Elliott 

Coues, as “ ... a notable contribution to our knowledge 

of early adventure and pioneering in the Great West. 

His style is straightforward and his wonderful power 

of observation has made the narrative very attractive.”

Fowler was a fur trader who left Fort Smith, Arkansas, in September 1821 and entered the valley via La 

Veta Pass on February 4, 1822. For the next 3 months, 

he traveled between Taos and the central part of the 

valley, going as far north as near where Fort Garland 

would be later established. Many animals are noted 

in the valley, including beaver, elk, deer, bear, pronghorn, otter, bighorn sheep, wild horses, geese, ducks, 

and a wolf. Although great herds of “buffelow” were 

noted as the party crossed the Plains, and as far west 

as the Wet Valley, there is no mention of them once 

they reach the San Luis Valley. As with the references 

to animals, the descriptions of plants, particularly 

the distribution (or lack thereof) of cottonwoods and 

willows along specific creeks, is frequent and often 

detailed. These descriptions are mixed with wonderful 

accounts of life in the many small Spanish settlements 

that dotted the landscape and interactions with the 

native peoples.

Fowler recorded an exceptionally astute observation while crossing the southern part of the valley on 

February 18, 1822:

I Have no doubt but the River from the Head 

of those Rocks up for about one Hundred miles 

has once been a lake of about from forty to 

fifty miles Wide and about two Hundred feet 

deep—and that the running and dashing of 

the Watter Has Woren a Way the Rocks So as 

to form the present Chanel.

With this Robert Fowler had speculated about some 

of the complex geological processes that formed the 

valley—processes that were studied and confirmed a 

hundred years later.

Many other explorers and settlers visited the valley 

and left behind journals of varying detail (Hart and 

Hulbert 2006, Kessler 1998, Preuss 1958, Richmond 

1990, Sanchez 1997). Among these are the following: 
Chapter 2—Area Description and Resources 25

■ George Frederick Ruxton, 1846

■ John C. Fremont, 1848 to 1849

■ Charles Preuss, 1848 to 1849 (traveling with Fremont)

■ Gwinn Harris Heap, 1853

■ John Williams Gunnison, 1853

■ John Heinrich Schiel, 1853 (traveling with Gunnison)

■ Randolph Barnes Marcy, 1858

■ William Wing Loring, 1858

■ Juan Bautista Silva, 1859

POLITICAL BOUNDARIES, LAND GRANTS, AND 

PUBLIC LANDS

The San Luis Valley has endured many changes in 

governance over the last 300 years. Following nearly 

12,000 years of sovereignty by various Native Americans, the control (or at least the declared control) and 

political boundaries of the region shifted continually 

until Colorado and New Mexico obtained statehood. 

The brief timeline below summarizes some of these 

changes in “ownership” of the San Luis Valley:

1598 Don Juan de Onate claims the San Luis 

Valley and surrounding areas for Spain.

1763 The Treaty of Paris at the end of the 

French and Indian War divides much of 

the North American interior between 

Spain and France. The San Luis Valley 

is considered Spanish territory.

1803 The Louisiana Purchase is negotiated 

between the United States and France 

but the western boundaries are not clarified and remain ambiguous.

1819 The United States negotiates the AdamsOnis Treaty with Spain to clarify the 

boundaries of the Louisiana Purchase. 

The San Luis Valley remains part of 

Spain’s New Mexico Territory. 

1821 Mexican War of Independence (1810 to 

1821). The valley becomes a part of the 

new nation of Mexico.

1836 The Republic of Texas achieves independence from Mexico. Texas claims the land 

in the valley east and north of the Rio 

Grande. Mexico does not recognize the 

Republic, disputes this boundary, and 

continues to claim the entire valley.

1837The United States recognizes the 

Republic of Texas, including the San 

Luis Valley.

1845The United States annexes Texas, 

including the San Luis Valley, and Texas 

achieves statehood.

1848 Following the Mexican-American War 

(1846 to 1848), the Treaty of Guadalupe 

Hidalgo establishes the present MexicoUnited States border except for the 

later 1853 Gadsden Purchase (southern 

Arizona and southern New Mexico).

1850Amid much controversy about the 

admittance of free versus slave States, 

and as a result of the Compromise of 

1850, Texas surrenders its claim to New 

Mexico, and the New Mexico Territory, 

including the San Luis Valley generally 

south of the Rio Grande (38th parallel), 

is established. 

1854 The Kansas Territory, which includes 

the northern part of the San Luis 

Valley (above the 38th parallel), is 

established out of unorganized lands of 

the Louisiana Purchases.

1861 The Colorado Territory is created by 

the Colorado Organic Act with the same 

boundaries that would later become the 

State of Colorado.

1876 Colorado becomes a State.

1912 New Mexico becomes a State.

Beginning in 1833, many Mexican land grants were 

issued in the valley as a direct result of the political 

turmoil noted above and the desire for Mexico City 

to keep control over the distant northern borderlands 

of their newly independent nation. These land grants 

were intended to encourage Mexican settlement in 

the borderlands, thereby dissuading any thoughts of 

Texas independence and discouraging encroachment 

by American fur traders. 

The first grants consisted of many small parcels along 

the Conejos River in Colorado in 1833 (Athearn 1985). 

These small grants were ineffective in establishing 

permanent settlement, but the much larger 1842 Conejos 

Grant proved to have more success in persuading the 

founding of farms and towns. This grant covered more 

than 2.5 million acres and included all of what would 

become the Colorado counties of Conejos and Rio Grande 

with parts of the counties of Mineral, Saguache, and 

Alamosa. As with other Mexican land grants in the 

valley, the grants were considered invalid following 

the Mexican-American War. The Court of Private Land 

Claims in 1900 ruled against the grantees and negated 

the claim (Colorado State Archives 2001).

The Sangre de Cristo grant included all of what is 

now Costilla County and extended a short distance into 

the current State of New Mexico. The grant consisted 
26 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

of 1 million acres and was originally awarded to two 

Mexican nationals in 1844, but following their deaths 

during the Pueblo Revolt of 1847, the land was sold to 

Charles (Carlos) Beaubien. Unlike the Conejos Grant, 

Beaubien’s claim to the land was upheld by the courts 

in 1860. The land was later sold to William Gilpin (Colorado’s first Territorial Governor) in 1864. Large tracts 

of the grant have been sold to various developers and 

disputes over the rights of local people to use the land 

have continued through 2009 (The Center for Grant 

Studies 2003, The Pueblo Chieftain 2009).

The Baca “Land Grant” in the San Luis Valley was 

the result of a land dispute. The Baca land patents, of 

which there are five, were granted to the heirs of Luis 

Maria Baca in replacement for his 1825 grant near Las 

Vegas, New Mexico, which was also claimed by Juan 

de Dios Maiese in 1835. These conflicting claims came 

to light when the United States took control of the 

lands in the mid-1840s. The Baca claim was settled in 

1860 and patented in 1903, when the Baca heirs were 

given five parcels of land: two in New Mexico, two in 

Arizona, and one in the San Luis Valley—Baca #4. In 

various configurations and sizes, the Baca #4 lands 

have changed hands many times over the ensuing 

hundred years, with a large part established as the 

Baca National Wildlife Refuge in 2000. 

The broader San Luis Valley region contains more 

than 40 percent public land. This includes large parts 

of the Rio Grande and the Pike-San Isabel National 

Forests in Colorado, with small sections of the Carson 

National Forest in New Mexico. The National Forest 

System was established at the turn of the 20th century as the American public became alarmed at the 

destruction of forests by timber and mining interests. 

The BLM was established in 1946 as a result of combining several agencies and policies into one bureau and 

now owns large parcels of land in the area, primarily 

in the western and northern parts of the valley floor. 

Great Sand Dunes National Park and Preserve was 

initially established as a national monument in 1932 

and was expanded to include many upland parcels in 

2004. Three national wildlife refuges, Monte Vista 

(1953), Alamosa (1962), and Baca (2003), were established to protect wetland habitat for migratory birds 

along the central flyway. Additional lands are owned by 

the Bureau of Reclamation and the State of Colorado.

NATIVE PEOPLES

The postcontact history of Native Americans in the 

San Luis Valley involves both cooperation and conflict 

and ends with the establishment of reservations outside of the valley. Although several Native American 

tribes are now represented in the valley, today they 

compose less than 1 percent of the current population.

The Utes consist of several bands and at the time 

of contact were the primary Native American inhabitants of much of Utah, central and western Colorado, 

and parts of northern New Mexico. Increased settlement after the United States gained possession of 

the valley in 1848 and the surrounding gold rush of 

1859 brought new people to the valley and ushered 

in several decades of escalating pressure to remove 

the Utes (Ellis 1996). Fort Massachusetts (1852–58) 

and Fort Garland (1858–83) were established in the 

valley primarily to protect settlers from Ute attacks. 

The 1863 and 1868 treaties between the United States 

and the Utes gave parts of Colorado, including the San 

Luis Valley, to the United States. Over the next four 

decades, a series of treaties and agreements continued 

to reduce Ute lands and relocate the Ute peoples, 

with the eventual establishment of three reservations 

in southwestern Colorado and northern Utah by the 

early years of the 20th century. 

Many other Native Americans visited or lived in 

the valley, including the Apache, Arapaho, Cheyenne, 

Comanche, Kiowa, and Navajo (NPS 2011). Early historical accounts frequently mention various members 

of pueblos along the Rio Grande coming north into 

the central San Luis Valley to hunt bison, causing 

occasional confrontations with the Utes (Carson 

1998, Colville 1995). The first Pueblo revolt of 1680, a 

response to the expanding Spanish control in northern New Mexico, effectively ceased Spanish rule in 

the region until Don Diego de Vargas reestablished 

control over the pueblos in 1692 and 1696. The Taos 

Pueblo rebelled against the occupation of United 

States troops during the Mexican-American War in 

1847, but the rebellion was soon repelled, effectively 

ending major conflicts in the region. 

SETTLEMENT

Settlement of the San Luis Valley reflects cultural, 

economic, and political influences as well as creative 

adaptation to a unique environment. Following the 

1610 establishment of Santa Fe as the capital of the 

New Mexico province, explorers and traders slowly 

made their way north into the central San Luis Valley. 

Jacob Fowler encountered several small Spanish 

settlements during his travels north of Taos and into 

southern Colorado in 1821 and 1822 (Coues 1965).

The Catholic Church, which was a primary influence 

during the initial exploration of the region, continued 

to play a major role in the establishment of settlements 

and in the day-to-day lives of most of the inhabitants. 

Members of various church orders were often part of 

the early explorations, such as the 22 Franciscans who 

accompanied de Onate during his 1598 exploration and 

settlement in northern New Mexico (Athearn 1989). 

The church was instrumental not only in matters of 

faith, but also as educators, trade coordinators, keepers of public records, and builders of comparatively 

grand architecture. On the other hand, the oppressive 

condemnation and suppression of the Native American religious practices were a major contributor to 
Chapter 2—Area Description and Resources 27

The ranching heritage extends back into the 17th century 

and is an important part of the San Luis Valley’s history 

and culture, as evidenced by the National Historic 

Register–listed Trujillo Homestead on Baca Refuge.

Meg Van Ness / USFWS

the unrest that led to the Pueblo Revolt of 1680 and 

the destruction of several missions. Nonetheless, the 

Catholic church began the 18th century as one of the 

few institutions in the area to prosper, and soon missions were established throughout the region (Athearn 

1989). The journals of a Jesuit order near Conejos from 

1871 to 1875 reveal days full of baptisms, marriages, 

deaths, prayers, attending to the sick, and rituals, 

with a persistent concern for obtaining basic supplies 

(Stoller and Steele 1982).

In her 1997 book on the San Luis Valley, Olibama 

Lopez-Tushar describes the first attempted settlement 

of the valley as that of George Gold (Gould) near the 

town of Costilla in 1848 (Lopez-Tushar 1997). This 

settlement was found to be in trespass of the lands held 

by the Sangre de Cristo Grant and Gold was evicted 

before establishing a colony, although the town of San 

Luis de Culebra was established on the land grant 3 

years later (Athearn 1985, Wyckoff 1999). The establishment of towns on the land grants was encouraged 

and within a few years the towns of San Pedro, San 

Acacio, Chama, and San Francisco were on the Sangre 

de Cristo Grant and the towns of Conejos, Guadelupe, 

Ortiz, and Magote were on the Conejos Grant.

Early settlements in the valley were established 

based on the traditional pattern of the Spanish plaza 

with homes, churches, and public buildings clustered 

around a central square and long narrow fields radiating out around the buildings and fronting a nearby 

creek, sometimes referred to as cordillera or plaza 

farming (Colville 1995). The extensive systems of early 

irrigation canals and water control structures supported small grain fields and gardens, some of which 

are still in use today. Several large canals and their 

associated laterals, including the Travelers Canal, the 

Empire Canal, and the Monte Vista Canal, were built 

in the 1880s in response to the increasing demand for 

the valley’s beans, corn, grains, and other vegetables. 

The extensive irrigation in the valley was recognized 

early as a source of future problems as noted by Major 

John Wesley Powell in his 1890 testimony before the 

Senate Special Committee on Irrigation and Reclamation of Arid Lands:

Passing into New Mexico, then, the water 

that practically heads in the high mountains 

of Colorado is largely, almost wholly, cut 

off from the Rio Grande, so that no portion 

of the water that heads in these mountains 

where there is great precipitation will cross 

the line into New Mexico (in the dry season). 

In a dry season, nothing can be raised in the 

lower region and sometimes the dry seasons 

come two or three together. (Siebenthal 1910)

The mining boom in the surrounding mountains in 

1859, the completion of the Denver and Rio Grande 

Railroad over the Sangre de Cristo Mountains and into 

the valley in 1877, and a vigorous advertising effort 

by land speculators led to a slow but steady increase 

in population in the latter half of the 19th century. 

Before the discovery of gold in 1859, the valley was 

the home of Colorado’s largest non-Native American 

population, and by 1870 the population of Conejos, 

Costilla, and Saguache Counties is estimated to have 

been approximately 5,000 (Wyckoff 1999). Speculators 

capitalized on the increasing number of immigrants 

heading west from the eastern United States and 

Europe, as is illustrated by the description of the 

valley in a 1884 promotional brochure:

Society is very good. The intelligence of average 

western people is far above those of the eastern 

States. Under the duck or buckskin coat of 

many a miner, farmer or stockman of Colorado 

is concealed diplomas from the best colleges 

of the east and Europe.

The climate is almost perfect. Extremes 

of heat or cold are unknown, and the land 

is one of almost perpetual sunshine by day, 

and cloudless skies at night. The healthfulness of the country is notorious, sickness 

almost unknown. No malaria, no cyclones, 

no deluges, and when the orchards of small 

fruits, apples, cherries and plums, and groves 

of shade trees are planted, the country will be 

as fruitful and beautiful as the land of Italy. 

(The Republican Publishing Company 1884)

By the early 1870s, the effect of hunting and 

development was already taking a toll on Colorado’s 

wildlife. In 1872, the Colorado Territorial Governor 

Edward N. Cook passed the first game laws to protect certain birds, bison, deer, elk, and bighorn sheep 
28 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

(Colville 1995). His words sounded the alarm that 

the wildlife needed protection:

I desire to say a word in favor of protecting 

our game—birds, beasts, and fishes—all of 

which are being wastefully destroyed ... and 

unless some law is passed ... the buffalo, elk, 

deer antelope and trout will soon become 

extinct, and Colorado will be robbed of the 

many attractions she today possesses.

SUMMARY OF KNOWN HISTORIC RESOURCES

Information about the recorded resources in the 

Colorado part of the San Luis Valley is summarized from data obtained from the Colorado Office of 

Archaeology and Historic Preservation in February 

2012. Similar trends can be extrapolated for the New 

Mexico part of the area. The Office of Archaeology and 

Historic Preservation data represent the efforts of 

hundreds of agencies, organizations, and individuals 

to document and study the past. The counts include 

sites, buildings, structures, and isolated finds; however, an individual resource may have many of these 

elements and may represent more than one time 

period (multicomponent) and therefore may be counted 

more than once. It is also important to note that the 

distribution of the known resources often shows where 

modern activities have mandated cultural resource 

surveys and may also potentially show recorder bias 

as much as actual prehistoric or historic settlement 

or use patterns. 

A total of 6,490 cultural resource sites or properties have been recorded in the Colorado part of the 

San Luis Valley. Another 2,740 isolated artifacts or 

features have also been recorded in this area. These 

resources include 4,719 prehistoric components, 4,091 

historic components, 62 components lacking a temporal 

designation, and 3 paleontological locations, with some 

resources representing multiple components. 

Nearly 20 percent of the prehistoric components 

are lithic scatters. These locations consist of stone 

tools or the remains associated with stone tool manufacture. Camps, which are lithic scatters in association 

with the remains of a campfire, are only slightly less 

common and have been recorded at approximately 

19 percent of the sites. The third most frequent prehistoric site type, representing 4 percent of the sites, 

is architectural, and generally consist of stone circles 

or alignments. Other relatively frequent site types 

found in the valley but never consisting of more than 

1 percent include peeled trees, rock art, and human 

burials. More than half of the prehistoric components 

on sites in the valley have not been classified into a 

particular type.

The 4,091 historic components include standing 

buildings or structures or historic archaeological 

deposits. Many of these are homes, commercial 

buildings, or public buildings within the towns in the 

valley, with 100 or more each recorded in Alamosa, 

San Luis, and Monte Vista. Rural sites with historical components often include water control structures 

(111 recorded), cabins or homesteads (68 recorded), 

roads or trails (62 recorded), and railroad-related 

features (28 recorded). The 1,635 historical archaeology 

components include both isolated rubbish scatters 

and small features in addition to artifacts or deposits 

associated with a building or structure.

Two resources in the valley have been designated 

as National Historic Landmarks. These include Pike’s 

Stockade (5CN75) from 1808 and the Pedro Trujillo 

Homestead (5AL706) from the late 19th century. 

Approximately 100 cultural resources in the valley are 

listed on the National or State Register of Historic 

Places. Another 435 resources are officially eligible to 

be listed on the National or State Registers but have 

yet to be formally nominated. 

Socioeconomic Environment

This section describes the socioeconomic profile, 

land use and ownership, SLVCA land conservation 

efforts, and water law in the area.

SOCIOECONOMIC PROFILE

The following narrative contains information 

about the area’s population and economics, including 

employment and the major industries of agriculture, 

recreation, and tourism.

Population 

The combined SLVCA and SCCA spans nine counties: Alamosa, Conejos, Costilla, Hinsdale, Mineral, 

Rio Grande, and Saguache Counties in Colorado and 

Rio Arriba and Taos Counties in New Mexico. Table 

1 lists population statistics for these counties. The 

nine-county region has a population of roughly 120,000 

people (U.S. Census Bureau 2010a). The counties in 

Colorado are home to approximately 47,000 residents. 

Most Hinsdale County residents live in the Gunnison 

river drainage. Consequently, four of the six counties 

in the Rio Grande drainage experienced population 

declines from 2000 to 2010. Slow growth may be the 

result of increasing unemployment, decreasing nonresidential construction, and declining prices of key 

agriculture commodities (such as barley, alfalfa, and 

potatoes in 2009) (Colorado Legislative Council Staff 

2011). From 2000 to 2010, the nine-county region experienced a 2-percent increase in population, representing slow growth relative to the statewide figures 

for Colorado (which had a 17-percent increase from 

2000 levels) and New Mexico (which had a 13-percent 

increase from 2000 levels). 
Chapter 2—Area Description and Resources 29

Population growth in the San Luis Valley region 

is expected to continue at a slow pace over the next 

decade. From 2010 to 2025, the population of the local 

area is projected to increase by 14 percent, indicating 

slow growth compared to the projected statewide figures for Colorado (which has a projected 26-percent 

increase) and New Mexico (which has a projected 

19-percent increase) (Colorado Department of Local Affairs 2002, University of New Mexico 2002). In 

the SLVCA, the smallest projected increases are in 

Costilla County (8 percent) (Colorado Department of 

Local Affairs 2002, University of New Mexico 2002).

Race, Ethnicity, and Education 

Hispanic and Latino residents (57 percent of the 

total population) represent the largest ethnicity in the 

nine-county San Luis Valley region. The prevalence 

of this ethnic group is because of the presence of two 

large Hispanic communities in the local area. The region is home to a large population of White residents 

who consider themselves to be of Hispanic or Latino 

ethnicity. This is particularly true in Alamosa, Conejos, Costilla, Saguache, Rio Arriba, and Taos Counties, where, collectively, White Hispanics represent 

32 percent of the county-wide population on average 

(U.S. Census Bureau 2010a). The occurrence of this 

race-ethnicity pairing in the San Luis Valley may be 

because of residents of Hispano heritage (such as descendants from Spaniards) (Sangre de Cristo National 

Heritage Area 2012). Hispanics of Mexican descent also 

represent a substantial share of the population in Costilla County (34 percent) (U.S. Census Bureau 2010a). 

Whites (including Whites of Hispanic and Latino 

origin) represent the largest race in the nine-county 

region (66 percent of the total population). Native 

Americans and Alaska Natives account for 8 percent 

of the total population of the region. Collectively, Black 

or African-American residents, Asians, and native Hawaiians and other Pacific islanders account for about 

1 percent of the total population of the region (U.S. 

Census Bureau 2010a). 

Table 2 shows the percent of the population that 

has obtained a bachelor’s degree or higher within 

each of the SLVCA States and counties. Of the two 

States, Colorado has the highest percentage of individuals with a bachelor’s degree or higher (36 percent 

of the population), followed by New Mexico (26 percent) (U.S. Census Bureau 2010a). Costilla County 

residents were less likely to hold a bachelor’s degree 

than the average Colorado resident; in New Mexico, 

the opposite is true for Taos County (30 percent of 

the county-wide population with a bachelor’s degree 

or higher) relative to the State average (26 percent) 

(U.S. Census Bureau 2010a). 

Regional Economy, Employment, and Income 

Table 2 also shows median household income and 

poverty rates for each of the SLVCA States and counties. Among the two States, Colorado had the highest 

median household income in 2010 ($56,456 per year), 

followed by New Mexico ($43,820 per year) (U.S. 

Census Bureau 2010b). At a statewide level, New 

Mexico had the highest poverty rate at 18.4 percent, 

and Colorado had the lowest at 12.2 percent. However, 

the San Luis Valley is one of the most impoverished 

regions of Colorado. Costilla County has the highest 

poverty level, more than twice the State average, 

and its median household income is less than half the 

State average at $24,388 per year. Taos County has 

somewhat higher median household income ($35,441 

per year) and its poverty level is lower than the State 

of New Mexico’s. (U.S. Census Bureau 2010b). 

Table 1. Population statistics for counties in Colorado and New Mexico that contain the San Luis Valley 

Conservation Area.

Residents (2010)

Persons per square 

mile (2010)

Percentage 

population change 

(2000–2010)

Percentage 

population change 

(2010–2025)†

Colorado 5,029,196 48.5 17 26

Alamosa County 15,445 21.4 3 25

Conejos County 8,256 6.4 –2 10

Costilla County 3,524 2.9 –4 8

Hinsdale County 843 0.8 7 26

Mineral County 712 0.8 –14 16

Rio Grande County 11,982 13.1 –3 7

Saguache County 6,108 1.9 3 18

New Mexico 2,059,179 17 13 19

Rio Arriba County 40,246 6.9 –2 11

Taos County 32,937 15 10 17

Sources: U.S. Census Bureau 2010a and †Colorado Department of Local Affairs 2002, University of New Mexico 2002.
30 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Table 3 shows the percent of employment by sector within the San Luis Valley region. The combined 

nine-county region had a total employment of more 

than 62,000 individuals in 2009 (U.S. Department of 

Commerce 2009). The highest percentage of total 

employment in 2009 was in public administration (18 

percent of total local employment), the second highest was in the arts, entertainment, recreation, and 

accommodation and food services (11 percent), and 

the third highest was in agriculture, forestry, fishing, 

hunting, and mining (11 percent) (U.S. Department 

of Commerce 2009).

Agriculture, Recreation, and Tourism 

Agriculture is a prominent industry in the San Luis 

Valley. Crops grown in the valley include alfalfa, native grass hay, wheat, barley, sorghum, canola, spinach, 

lettuce, carrots, and potatoes (Colorado Division of 

Wildlife 2010). Agriculture, forestry, fishing, hunting, 

and mining accounted for roughly 11 percent of the 

total jobs in the region in 2009 (U.S. Census Bureau 

2009). The total number of agricultural jobs in the local 

area increased from about 3,700 jobs in 1970 to 4,446 

in 2009 (U.S. Department of Commerce 2010a). Costilla County, Colorado, had the largest percentage of 

employment in agriculture in the region (22 percent) 

(U.S. Department of Commerce 2010a, U.S. Department of Commerce 2010b; data compiled using the 

EPS–HDT system [Headwaters Economics 2011]). 

Approximately 29 percent of the land in the ninecounty region is in agriculture (U.S. Department of 

Agriculture 2009, data compiled using the EPS–HDT 

system [Headwaters Economics 2011]).

Tourism is a cornerstone of the local economy, and 

the tourism industry in the San Luis Valley shows 

strong development potential. With a diverse collection of natural and heritage assets, the local tourism 

industry is able to cater to a variety of recreationists, 

including outdoor recreationists; visitors to the Great 

Sand Dunes National Park and Preserve; resort tourists; vacation and second home owners; ecotourists; 

heritage, arts, and cultural tourists; and visitors who 

pass through the area on their way to other regional 

attractions (Center for Rural Entrepreneurship 2008). 

According to the 2006 National Survey of Fishing, 

Hunting, and Wildlife-Associated Recreation, approximately 3.1 million residents took part in wildlifeassociated recreation activities in Colorado and New 

Mexico in 2006 (USFWS 2008). It was estimated that 

residents and visitors combined spent $3.8 billion on 

wildlife-associated recreational activities in 2006 in 

the two States combined, with Colorado accounting 

for approximately 79 percent of this spending. Among 

participants, wildlife watching was the most frequently 

reported activity, followed by fishing and hunting. In 

Colorado, 82 percent of individuals’ surveyed watched 

wildlife, 30 percent fished, and 12 percent hunted, 

while in New Mexico, 83 percent watched wildlife, 26 

percent fished, and 10 percent hunted (USFWS 2008). 

LAND USE AND OWNERSHIP CHANGES 

SURROUNDING THE CONSERVATION AREA 

The current land use and changes in land use are 

described below.

Table 2. Income, education, unemployment, and poverty rates for counties in Colorado and New Mexico that 

contain the San Luis Valley Conservation Area.

Median 

household 

income

(average 

$2006–2010)†

Percentage 

bachelor’s degree 

or higher†

Percentage unemployed‡ Percentage of 

individuals 

below poverty 

(average 

2008 2011 2006–2010)†

Colorado 56,456 36 4.8 7.9 12

Alamosa County 35,935 27 5.2 7.5 24

Conejos County 33,627 19 7.3 9.5 18

Costilla County 24,388 14 7.7 12.4 28

Hinsdale County 74,659 42 3.4 6.1 4

Mineral County 53,438 39 5.4 7.3 8

Rio Grande County 39,871 19 5.6 7.8 17

Saguache County 30,430 19 7.2 9.9 24

New Mexico 43,820 26 4.5 6.6 18

Costilla County 41,437 16 5.4 8.9 20

Taos County 35,441 30 5.5 10.4 17

Sources: †U.S. Census Bureau 2010b and ‡ Bureau of Labor Statistics 2011a, Bureau of Labor Statistics 2011b, Bureau of Labor 

Statistics 2008.
Chapter 2—Area Description and Resources 31

Current Land Use 

The San Luis Valley is a large intermountain basin 

covering approximately 3,200 square miles of land in 

southern Colorado and northern New Mexico. The 

valley is bordered by the Sangre de Cristo Mountains 

to the east and northeast, the San Juan and La Garita 

Mountains to the west and northwest, and the Taos 

Plateau to the south. Snowmelt from the mountains 

around the valley is responsible for most of the area’s 

stream flow in the associated watershed, including the 

Rio Grande and Conejos Rivers (Emery [no date]). 

The valley floor is primarily grassland and shrubland, 

while the hills surrounding the valley are forested. 

Collectively, grasslands (40 percent of all land cover 

in the nine-county region), forests (30 percent), and 

shrublands (22 percent) account for most of the land 

cover in the local area (NASA 2006; data compiled 

using the EPS-HDT system [Headwaters Economics 

2011]). Approximately 56 percent (2,944,353 acres) of 

the project area is in private ownership. The remaining acres are protected and managed by the Service, 

USFS, BLM, National Park Service, and State of Colorado. Most of the private land and wetland habitat 

occurs on the valley floor, creating one of the largest 

intermountain valleys in the world (USFWS 2010a). 

The nine-county region is relatively rural, and 

population densities in the San Luis Valley are among 

the lowest in Colorado. Only 2 percent of land cover in 

the region area is urban (NASA 2006, data compiled 

using the EPS–HDT system [Headwaters Economics 

2011]), U.S. Census Bureau 2010a). Major municipalities 

in the region include Alamosa, Crestone, Del Norte, 

Monte Vista, Saguache, and San Luis. 

Changes in Land Use

The SLVCA contains a rich diversity of trust species 

and habitat types. The San Luis Valley is the southernmost significant waterbird production area in the 

central flyway and is the most important waterfowl 

production area in Colorado. According to Partners 

in Flight, riparian habitats in the region support the 

highest bird diversity of any western habitat type 

(USFWS 2010a).

Historically, land use remained unchanged in the San 

Luis Valley until the early 1800s, when Euro-American 

settlement began to alter the presettlement landscape 

(USFWS 2010a). During this period, livestock grazing, farming, and water development began to affect 

ecosystem processes such as the natural hydrological 

regime. Since then, nearly 50 percent of Colorado’s 

wetlands have been lost (Dahl 1990, 2000). 

The highest remaining concentration of wetlands 

in Colorado occurs in the San Luis Valley, and protection of every remaining wetland acre is a high priority 

(USFWS 2010a). Manipulation of the natural hydrological cycle in the San Luis Valley for agricultural purposes likely has resulted in a significant conversion of 

upland habitat to wetland habitat through the extensive 

development of flood-irrigation infrastructure. These 

conversions have benefitted many wetland-dependent 

species, with tradeoffs. The results of these conversions of uplands to wetlands included the 

Table 3. Percentage employment by sector for counties in Colorado and New Mexico that contain the San Luis 

Valley region.

Employment sectors

Percentage of nine-county

 region employed

Total employment in 2009a was 62,121

Agriculture, forestry, fishing, hunting, and mining 11

Arts, entertainment, recreation, and accommodation and food services 11

Construction 6

Educational services, health care, and social aid 8

Finance and insurance, real estate, rental, and leasing 6

Information 1

Manufacturing 2

Other services, except public administration 4

Professional, scientific, management, administrative, and waste-management services 5

Public administration 18

Retail trade 10

Transportation and warehousing, and utilities 2

Wholesale trade 2

Source: U.S. Department of Commerce 2009

aNot every sector category for every county was fully disclosed because of confidentiality requirements; the table reflects the best and 

most correct information available.
32 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

shortening of some streams and the alteration of annual hydrographs in many stream reaches, which have 

lowered the peak in the hydrograph yet increased flows 

after the irrigation season due to unconsumed water 

returning to the stream system. Stream depletions 

from the use of wells have compounded these effects. 

Chronically reduced levels of runoff from the San Juan 

and Sangre de Cristo Mountains have increased all of 

these effects on streams. Most wetland habitat in the 

SLVCA is on private ranch and farm lands and relies 

on surface and ground water diversions to maintain 

its value to wetland-dependent wildlife. Through the 

SLVCA, we hope to maintain these land management 

practices with willing landowners to support priority 

wildlife habitat. 

In recent years, human population growth has occurred in rural areas causing fragmentation of wetland habitat types throughout the SLVCA. Statewide, 

Colorado’s population grew by more than 36.9 percent 

between 1990 and 2003. During that same time, Mineral County’s population grew by 57.9 percent and 

Saguache County’s by 45.2 percent. While population 

densities are still low in these counties, the amount of 

habitat loss and fragmentation resulting from subdivision of lands for residential and commercial development is a significant threat to trust wildlife species 

in the SLVCA. 

Exurban housing development typically occurs 

within riparian areas in the SLVCA. This is detrimental 

to wildlife habitat because riparian habitats account 

for only a limited portion of Colorado’s landscape, but 

contain high species richness and abundance. Additionally, most of the wetland and riparian habitat in the 

SLVCA occurs on private ranchland and farmland. 

The recent downturn in the economy coupled with 

depressed agricultural markets have increased the 

rate of exurban development, as some ranchers and 

farmers have been forced to subdivide their properties to continue operating (USFWS 2010a). 

As agricultural lands are subdivided, the resulting fragmentation can affect habitat use for a wide 

array of waterfowl, shorebird, colonial waterbird, 

and songbird species. Many of these species require 

specific habitat conditions for successful reproduction 

and building energy reserves for breeding and migration. As habitats are lost, the spatial juxtaposition of 

available habitat is altered, disrupting wildlife movement, dispersal, and migration patterns. 

In addition to the direct loss of wildlife habitat from 

fragmentation, the water rights associated with these 

properties are subject to sale, potentially resulting in 

not only the loss of wetland habitat and wetland functions on the subdivided property but also on adjoining 

lands as the water is redistributed off of the property. 

Keeping the current connectedness of habitat through 

permanent protection will limit the risk for disruption 

of species’ movement patterns because of fragmentation. Connectivity will also keep important migration 

Agricultural practices such as haying and grazing are a primary part of the economy in the San Luis Valley, and often 

provide habitat for wildlife as well.

USFWS
Chapter 2—Area Description and Resources 33

corridors and linkages between seasonal ranges necessary to meet the life history needs for many species 

(USFWS 2010a).

Currently, the landscape of the San Luis Valley has 

not been altered to the extent found in many other 

western regions with more rapid population growth. 

The downturn in the national and regional economy 

has slowed population growth and development pressures. Although the overall population of the project 

area only increased by 2 percent between 2000 and 

2010, it is projected to increase by 16 percent between 

2010 and 2025, with greater increases in Alamosa, Hinsdale, and Taos Counties (U.S. Census bureau 2010a). 

Any pressures on the agricultural economy of the San 

Luis Valley can result in conversion of agricultural land 

to other uses potentially resulting in fragmentation 

and loss of critical wildlife habitat, including riparian 

habitat. Whether or not agricultural lands change 

ownership, there is potential for water to be sold and 

transferred off the property, often to the detriment 

of wildlife habitat, but only after a change of water 

right is filed and approved by the court. 

As explained previously, the overall population in 

the SLVCA increased by only 2 percent between 2000 

and 2010. The largest increase in population growth 

occurred in Hinsdale County (7 percent increase from 

2000 levels) and Taos County (10 percent increase from 

2000 levels), while five of the nine counties in the region (Conejos, Costilla, Mineral, Rio Arriba, and Rio 

Grande) experienced population declines during these 

years (U.S. Census Bureau 2010a). From 2010 to 2025, 

the population in the SLVCA is projected to increase 

by 16 percent, indicating slower growth relative to 

the projected State-level increases of 26 percent for 

Colorado and 18 percent for New Mexico (Colorado 

Department of Local Affairs 2002, University of New 

Mexico 2002). However, the population is projected 

to increase at rates similar to the Colorado State average in Alamosa County (25 percent increase) and 

Hinsdale County (26 percent increase) and above the 

New Mexico State average in Taos County (21 percent increase). 

In 2000, the American Farmland Trust identified 

4.9 million acres of prime ranchlands in Colorado and 

2.6 million acres in New Mexico as being vulnerable 

to low-density development by the year 2020. Within 

the Rocky Mountain region (which includes 263 

counties in Idaho, Montana, Wyoming, Utah, Colorado, Arizona, and New Mexico), Saguache County, 

Colorado, and Rio Arriba County, New Mexico (both 

close to the project area), ranked in the top 25 counties for acres of strategic ranchland at risk (American 

Farmland Trust 2000). While population densities are 

still low in these counties, development has been occurring within sensitive riparian areas in the valley 

floor. Taking added steps to conserve wildlife habitat 

in the San Luis Valley now, while land prices are still 

Much of the plant and animal diversity of the San Luis 

Valley is dependent on its sensitive wetland habitats. 

© Joe Zinn

affordable and irreplaceable habitat has not been lost, 

may be proper. Protecting this land from residential 

and industrial development is the only way to ensure 

the long-term resiliency of the ecosystem and support 

viable wildlife populations and habitats in the face of 

climate change and other threats (USFWS 2010a).

Water quantity, quality, and use issues are major 

threats to the sustainability of wetland and riparian 

habitats in the SLVCA. Changes in water quality and 

quantity have adverse effects on the function of the 

wetland complex located in the valley floor. There are, 

for example, growing concerns about the impacts of 

new contaminants, such as endocrine-disrupting chemicals, that can affect water quality on both private and 

public lands (USFWS 2010a). 

Ground water usage, especially artesian well development, started during the early 1900s. The result has 

been the construction of more than 7,000 wells in the 

San Luis Valley and development of one of the world’s 

largest concentrations of center pivot irrigation systems, some of which depend solely upon ground water. 

As a consequence, water users and regulators have 

acknowledged that annual ground water use chronically exceeds recharge under the current hydrologic 

cycle. New ground water use rules were developed 

by the Colorado Division of Water Resources in late 

2015 and may soon be applied to well owners in the 

San Luis Valley (USFWS 2010a). 
34 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Once the new ground water rules are carried out, 

ground water users will be responsible for eliminating 

injury to senior water rights through a process with 

the State (USFWS 2010a). The Rio Grande Water 

Conservation District, who is working with ground 

and surface water users, is offering an alternative 

approach of establishing ground water management 

subdistricts. These self-taxing entities will be responsible for collectively replacing injurious depletions 

to senior water right holders caused by the ground 

water use of its members and ensuring ground water use within the subdistricts is sustainable. In most 

cases, this will require ground water users to acquire 

and, in many cases, remove senior water rights from 

other properties to replace depletions from well use. 

These circumstances threaten healthy riparian 

systems along the tributaries of the Rio Grande, including in the SLVCA, where senior water rights 

are now used to irrigate meadows and grasslands in 

the floodplain. The evolving economic and regulatory 

environment in the SLVCA may likely result in the 

acquisition of some of these water rights to augment 

distant wells, moving water out of the floodplain and 

degrading migratory bird habitat (USFWS 2010a).

SAN LUIS VALLEY CONSERVATION AREA LAND 

CONSERVATION EFFORTS

Land protection is a relatively new practice in 

the San Luis Valley, as most conservation easements 

have been completed within the last 10 years. However, during this short timeframe, more than 232,000 

acres of land have been protected in the region, which 

suggests that public support for land protection in the 

SLVCA is strong (USFWS 2010a). In fact, there are 

so many landowners interested in entering into conservation easements that organizations like the Rio 

Grande Headwaters Land Trust, The Nature Conservancy, Ducks Unlimited, and NRCS are challenged 

to meet the demand (USFWS 2010a). Citizens of the 

San Luis Valley understand that the rural lifestyle 

and wildlife habitat is what makes this area unique 

and have voiced their concern over the loss of these 

values. They recognize that conservation easements 

are a tool to keep both ranches and wildlife habitat 

intact (USFWS 2010a).

The Service plans to conserve up to 280,000 acres 

to protect the remaining expanses of wildlife habitat 

in the SLVCA. This will be accomplished primarily 

through the purchase of conservation easements by 

the Service on a voluntary basis from private landowners. Other Federal, State, and nongovernmental 

partners may assist in acquiring conservation easements or fee title to a lesser extent. On a limited basis, we may use fee-title acquisition to acquire land 

and water to facilitate more efficient management of 

the three national wildlife refuges. For example, we 

hope to explore the feasibility of acquiring more land 

on the west side of the Rio Grande next to Alamosa 

Refuge to reduce fencing problems and enable consistent management of this important stretch of riparian habitat. Examples of water acquisitions we are 

considering are (1) those needed to maintain current 

ground water rights on the refuges, (2) those rights 

associated with any fee-title land acquisitions, and (3) 

purchase of more shares in mutual ditch companies 

that currently serve the Alamosa and Monte Vista 

Refuges because of the need to also replace depletions 

from existing ground water uses.

Acquisition of these lands will occur over a period 

assumed to range from 15 to 20 years but, based on 

past acquisition rates, could reasonably be expected 

to occur over a longer period, possibly up to 100 years. 

Conservation Easements

One of the Service’s high-priority objectives is to 

guide residential and commercial development away 

from high-priority conservation areas by securing 

strategic conservation easements. The SLVCA will 

focus on the protection of wetlands, riparian areas, 

montane forests, and sagebrush habitats on private 

land within the area through acquisition of conservation easements from willing sellers. Conservation 

easements leave land in private ownership, protecting private property rights, while providing the Service with a cost-effective conservation strategy that 

enables the conservation of large blocks of habitat. 

A conservation easement is a voluntary legal agreement entered into between a landowner and a conservation entity. Conservation easements are binding in 

perpetuity; the landowner reserves the right to sell 

or bequeath the property, but the easement and its 

associated restrictions remain with the property forever. Owners of land that does not contain a conservation easement have a set of rights associated with 

their land. For example, landowners have the right 

to run cattle, grow crops, harvest trees, build structures, and subdivide and sell their land. Under a conservation easement, landowners keep ownership of 

their property, but transfer some of their ownership 

rights to the conservation entity. The most common 

right transferred under a conservation easement is 

the right to develop or subdivide the land. 

Conservation easements in the SLVCA may require 

the transfer of more rights. A conservation easement 

on a parcel of land may have restrictions for all types of 

human development, such as surface disturbance from 

solar, mineral, or wind energy development, depending upon the particular wildlife values of the habitat. 

In most cases, a conservation easement acquired 

for wetland values will be associated with appurtenant 

irrigation water rights that have resulted in desirable 

wildlife habitat. Doing anything less may often result 

in separation of water use from the land, reducing the 

easement’s value to trust wildlife species. 
Chapter 2—Area Description and Resources 35

Several nonprofit organizations active in the SLVCA 

that hold many easements are already acquiring the 

property rights to separate water from the land subject to the easements. Water use must respect State 

requirements; therefore, water issues will need to be 

addressed individually for each easement. In all cases, 

the terms of a conservation easement must be mutually agreed-upon by the landowner and the easement 

holder. Conservation easements acquired from private 

landowners will not affect their property rights beyond those purchased through conservation easement. 

Subsurface rights are often severed from the surface 

rights of a parcel of land. In such cases, conservation 

easements apply only to surface rights; therefore, the 

mineral interest may be extracted at any time by the 

person who holds the qualified mineral right (Byers 

and Ponte 2005). For this reason, the Service is unlikely 

to enter into a conservation easement agreement for a 

parcel of land that has a viable subsurface mineral interest. Exceptions may be made if the parcel has high 

habitat value and the probability of mineral extraction 

is low as determined by a formal remoteness survey. 

Fee-Title Purchases

Within the SLVCA, the Service may purchase limited property in fee title at fair-market value to protect 

up to 30,000 acres of significant wildlife habitat and 

maintain wildlife populations, plant communities, and 

ecosystem processes in perpetuity (USFWS 2010a). 

Under fee-title purchases, full ownership of the land, 

including the underlying title, is transferred to another 

party. This gives the new owner maximum interest in 

the purchased land and allows the new owner to manage the land in any manner that is consistent with local, State, and Federal laws. For fee-title acquisitions, 

the Service intends to evaluate the purchase of water 

rights with each property. We will consider acquiring 

land in fee title only where the Service’s conservation 

objectives could not be met with conservation easements. The Service will consider fee-title acquisition 

under the following scenarios:

1. A priority of this plan is the protection of wetlands 

still further west of Alamosa Refuge—identified as 

the Alamosa Marshes by the 1874, 1875, and 1877 

Wheeler Expedition (U.S. Army Corps of Engineers 

1878). The area still provides one of the largest intact wetland complexes in the San Luis Valley and 

provides significant migration and breeding habitat for waterfowl, shorebirds, and wading birds on 

average or above water years. We envision that 

conservation easements—with nonprofit organizations, the Service, or other agencies—will be 

the primary method of protecting these wetlands. 

We also recognize that some landowners may be 

willing to sell property for wildlife conservation 

purposes but unable or unwilling to pursue easements. To allow for this circumstance, the Service 

will have the ability to acquire fee-title interest in 

lands within the Alamosa Marshes.

The tributaries of the Rio Grande are some of the last refuges of genetically pure populations of Rio Grande cutthroat 

trout, and provide important nesting and migration habitat for countless birds.

Sue Olievira / USFWS
36 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

1. An important acquisition idea is to expand the 

western boundary of the Alamosa Refuge to include 

riparian habitat along the Rio Grande that is not 

already part of the refuge. Currently, some of the 

refuge boundary runs down the middle of the Rio 

Grande. Other parts of the boundary are located 

on the east side of the river, while the remainder 

includes land only on the west side of the river. 

This configuration makes livestock management 

very difficult on both sides of the refuge boundary. 

By including the entire riparian zone within the 

refuge, we will be able to improve management 

for riparian habitat species like the southwestern 

willow flycatcher.

2. The Service needs to have the ability to meet administrative challenges such as those resulting 

from upcoming ground water regulation that may 

require the Service to acquire surface water for 

ground water augmentation purposes. Although 

Colorado allows water to be sold separately from 

the land, the owner may choose not to do so. In 

this situation, the Service’s best alternative may 

be to buy from willing sellers both the land and 

the associated water rights to achieve our ground 

water management goals. The Service also wants 

the ability to make small boundary adjustments to 

all three national wildlife refuges to prevent refuge 

management conflicts.

The total lands acquired in fee title by the Service 

over the life of this plan depend on several variables 

including the following:

■ the priorities and success of our partners in protecting these lands

■ the willingness of private landowners to sell any 

property rights

■ private landowner preference of whether to sell 

fee-title or much more limited property rights

■ the availability of refuge operation and maintenance funds

■ the availability of land acquisition funding. 

This plan places a maximum cap of fee-title acquisition by the Service at 30,000 acres, but these influencing factors will inhibit or preclude the need for such 

acquisition and dictate the amount of land acquired 

over the life of the plan.

WATER LAW

To address water rights affecting the SLVCA, the 

following narrative describes water law in Colorado 

and New Mexico. In either State, water rights that 

the Service owns or acquires must conform to the 

respective State water adjudication process as required 

by the McCarran Amendment (43 U.S.C. § 666), 1952.

Colorado

Colorado is divided into seven water divisions using watershed boundaries. Each division has a Water 

Court and a division engineer who administers water 

rights by priority. The Rio Grande is in division 3. This 

method of administration has been in use since 1969, 

when the original statutes governing water were revised and rewritten.

Water rights in Colorado are subject to the prior 

appropriation doctrine, which is enshrined in the Colorado Constitution and dates from before statehood in 

1876. The first entity to claim the water right has the 

first right to use the full amount of water they claimed 

for beneficial use. The prior appropriation doctrine allows State officials to properly manage and distribute 

water according to the decreed priority dates. There 

are four elements of a water right under the prior appropriation doctrine: intent, diversion, beneficial use, 

and priority. An applicant must show that there is intent to use the water, construct the diversion works, 

and put the water to beneficial use, which establishes 

a priority date. In Colorado, every water right must 

be adjudicated through the Water Court. Colorado 

law now recognizes certain beneficial uses that do not 

require a diversion, such as instream flows.

If there is not enough water to satisfy all water 

right holders in a particular stream, the State must 

shut off junior rights as necessary to make sure that 

senior water right holders receive their full appropriation. The Rio Grande basin in Colorado is considered 

overappropriated, meaning that more water rights 

exist than can be continuously served by the average 

amount of available water supply. 

Ground water in Colorado is designated as either 

tributary or nontributary. Tributary ground water 

is water contained in aquifers that have a direct hydraulic connection to surface water. The unconfined 

and confined aquifers in the San Luis Valley are both 

considered tributary ground water. Tributary ground 

water is treated administratively the same as a surface water diversion.

Water rights in Colorado can be transferred from 

one entity to another, but a change application must 

be filed and approved by the Water Court. The amount 

available for transfer is limited to the consumptive 

use part of the right. Water rights in Colorado are 

considered real property and they may be bought or 

sold. A water right can be conveyed either as part of 

a piece of property or separate from a property. If a 

water right is transferred separately from the land, 

it is necessary to file a change application through the 

Water Court to use it at any other location.
Chapter 2—Area Description and Resources 37

In 1973, the Colorado Legislature passed Senate 

Bill 97, creating the State’s Instream Flow Program. 

This program, one of the first of its kind, vested the 

Colorado Water Conservation Board with exclusive 

authority to protect streamflow through a reach of 

stream rather than just at a point, and to protect 

levels in natural lakes. Until this law was passed, all 

appropriations of water in Colorado were required to 

divert water from the natural stream. 

Since about 1990, Colorado clarified the Colorado 

Water Conservation Board’s authority to acquire existing, decreed senior water rights on a voluntary basis from willing owners for instream flow uses. New 

appropriations are junior water rights claimed by the 

board to preserve the natural environment. New appropriations are considered by the board each year 

and are filed annually with the Water Court for adjudication. New appropriations are generally limited to 

the minimum amount necessary to protect the natural 

environment to a reasonable degree.

New Mexico

New Mexico’s water law is also based on the doctrine of prior appropriation. All waters in New Mexico 

are declared to be public and subject to appropriation 

for beneficial use. Apart from water rights acquired 

before 1907 and small-scale stock watering (10 acre-feet 

or less), a permit from the State engineer is required 

to appropriate water, change the point of diversion, 

change the location of wells in declared basins, divert 

or store water, or change the place or purpose of water 

use. There is a new requirement in New Mexico that 

before obtaining a water right involving the use of public lands, the person seeking the right must prove that 

he or she actually has a permit to use the public lands. 

The New Mexico ground water code was enacted in 

1931. Ground water procedures closely parallel those 

for surface water, with several important differences. 

A permit to drill a well and appropriate water is not 

required in areas outside of declared “undergroundwater basins.” Within underground water basins, 

however, use is regulated by the State engineer. The 

State engineer has the authority to establish these 

basins when regulation is necessary to protect prior 

appropriations, make sure that water is put to beneficial use, and support orderly development of the 

State’s water resources. There are now 33 declared 

underground water basins throughout New Mexico.

Water rights in New Mexico can be transferred from 

one entity to another, but a change application must 

be filed and approved by the State engineer. Water 

rights in New Mexico are considered real property 

and they may be bought or sold. A water right can 

be conveyed as part of a piece of property or separate from a property, as long as that water right has 

been severed from the land by an approved application through the State engineer. Water rights in New

Mexico are considered real property and they may be 

bought or sold. A water right can be conveyed as part 

of a piece of property or separate from a property, as 

long as that water right has been severed from the land 

by an approved application through the State engineer.

New Mexico has had adjudicated water rights 

since 1907. In an adjudication suit, each claimant has 

an opportunity to present evidence of water right to 

the court. The completion of adjudication results in a 

court decree outlining the priority, amount, purpose 

(determination of use), periods, and place of water use.

New Mexico’s instream flow program is complex, 

unclear, and continually evolving. New Mexico does 

not have a legislated instream flow program, and instream flow is not a recognized beneficial use. Recent 

case law, however, has allowed the development of an 

instream flow program in New Mexico. In 1998, the 

New Mexico Attorney General issued a legal opinion 

concluding that the transfer of a consumptive water 

right to an instream flow right is allowable under State 

law. The legal opinion found that instream uses such 

as recreation and fish and wildlife habitat are beneficial uses, and that transfers of existing water rights 

to instream flows are not expressly prohibited. Before 

this opinion, New Mexico was the only State that did 

not recognize instream flow as a beneficial use.

The 1998 Attorney General’s opinion is limited 

to the transfer of existing water rights. The opinion 

notes that new appropriations of water for instream 

flow are not subject to this precedent. Although the 

opinion concludes that there are no legal barriers to 

the transfer of existing water rights to an instream 

flow right, the State engineer still has the responsibility for approving such a transfer. Although 

instream flow in itself is not recognized as a beneficial use, it appears that water can be dedicated to 

instream flow for the purpose of recreation or fish 

and wildlife habitat.

The Attorney General’s opinion does not explicitly 

address the issue of ownership of instream flow rights. 

Since ownership of other types of water rights are 

not limited, it could be interpreted that instream flow 

rights could be held by a public or private entity. Current law is unclear and continues to develop.

Chapter 3—Threats to and 

Status of Resources

Threats to Resources

The land cover of the San Luis Valley was largely 

unaltered, except by natural processes, until the 

19th century, when human land use associated with 

settlers of European origin began to alter the landscape. During this period, livestock grazing, farming, 

and water development also began to affect ecosystem 

processes such as the historical hydrological regime. 

Since then, Colorado has lost nearly 50 percent of its 

wetlands (Dahl 1990, 2000). The highest remaining 

concentration of wetlands in Colorado occurs in the 

San Luis Valley, and their protection is a high conservation priority. Sagebrush-dependent birds are 

often sensitive to vertical structure in their habitat, 

and thus the protection of these habitats from development is a priority.

DEVELOPMENT

Population growth, primarily exurban development, 

led to habitat fragmentation in the San Luis Valley in 

the latter part of the 20th century and the first part 

of the 21st century. Colorado’s population increased 

by nearly 17 percent between 2000 and 2010 (U.S. 

Census Bureau 2010a). The absolute population numbers and densities are still low in the project area, as 

with the population growth. However, habitat loss and 

fragmentation because of residential and commercial 

development remain a threat to trust species in the 

SLVCA based on population growth projections. This 

rapid statewide growth has lessened somewhat during 

the current economic downturn, with relatively stable 

populations in the counties of the San Luis Valley from 

2000 to 2010 (U.S. Census Bureau 2010a). However, 

subdivision of ranchlands and farmlands will continue 

and may increase as ground water regulation goes 

into effect and changes the economic viability of some 

properties currently in agriculture. It is not the intent 

of the SLVCA to freeze all residential development 

at today’s level but to give owners of important wildlife habitat an alternative to such development in the 

effort to protect the highest priority habitat. 

As the country increases its dependence on renewable energy sources, we need to take care to minimize the effects on high-priority wildlife habitat. The 

effects on wildlife populations from solar energy 

development are of particular concern in the San Luis 

Valley, as interest in industrial solar electric–generating facilities has increased during the last decade. The 

San Luis Valley is already the site of two, large photovoltaic projects. Economically viable wind energy 

potential is generally quite low in most of the valley 

(Hanser 2010) and thus unlikely to be an issue in the 

near term. Hydrocarbon potential is low throughout 

the valley (Copeland et al. 2009), although some oil 

has been found during mineral exploration (Watkins 

et al. 1995). There is potential for further oil and gas 

exploration in this region, which the Service has found 

is unlikely to have significant impacts on the living 

resources of the valley (USFWS 2011). 

FRAGMENTATION

Changes in land cover because of exurban development, energy development, roads, and changes in 

agricultural land use (such as transition from flood 

irrigation to center-pivot irrigation) not only cause a 

loss of habitat, they also fragment the remaining habitat. There is a robust body of literature on the effects 

The forests along the mountains are a corridor for 

movement of wide-ranging species such as mountain 

lions.

Steve Torbit / USFWS
40 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

of habitat fragmentation, summarized eloquently by 

Collinge (2009). Countless manipulative and observational studies have shown that habitat area and connectivity among types of similar habitat are important 

for everything from soil decomposers (Rantalainen et 

al. 2005) to passerine birds (Telleria and Santos 1995). 

Corridors between fragments promote use of, and persistence in, those habitats by migratory birds (Haas 

1995), large carnivores (Shepherd and Whittington 

2006, Tremblay 2001), and ungulates (Tremblay 2001) 

that are native to the SLVCA. Perhaps the most obvious way to protect corridors throughout the SLVCA, 

while protecting valuable habitat at the same time, 

is to focus on the conservation of the riparian corridors that cross and connect existing protected areas. 

This action will protect wildlife movement corridors 

for both seasonal migration and colonization following large-scale disturbance or environmental change.

INVASIVE SPECIES

Increased human disturbance associated with 

development has also been shown to negatively affect 

adjoining habitat because of the invasion and establishment of invasive plant species. Invasive plants 

can have many detrimental effects; besides displacing 

native vegetation, they can alter nutrient cycling and 

soil chemistry, change hydrology, increase erosion, and 

change fire regimes (Dukes and Mooney 2004). Noxious weeds, such as tall whitetop, Canada thistle, and 

Russian knapweed, can have severe negative effects 

on wildlife habitat (such as reducing the quality of 

nesting and foraging areas) when these weed species 

begin to replace native vegetation. The San Luis Valley 

already has one of the densest concentrations of 

Russian knapweed in the State of Colorado (Goslee et 

al. 2003). Other invasive species that could threaten resources in the SLVCA include New Zealand mudsnail, 

quagga and zebra mussels, and Asian clam. Diseases 

such as white-nose syndrome, chytrid fungus, whirling disease, and chronic wasting disease also threaten 

wildlife and fish in the San Luis Valley.

WATER RESOURCES

In addition to the threats of the direct loss of habitat and fragmentation that accompany subdivision for 

exurban development, water rights can be sold with 

the property, or can be severed and sold to other landholders. This can result in the loss of wetland habitat 

and wetland functions not only on the property, but 

also on adjoining lands as the water is redistributed 

off of the property, directly affecting wildlife populations that depend on the wetlands to complete their 

life cycle. As fragmentation increases, remaining 

habitats become geographically isolated and wildlife 

Water is a critical resource to breeding and migratory birds in the high desert. Many wetlands and riparian areas have 

been lost due to ground water pumping and surface water diversion.

USFWS
Chapter 3—Threats to and Status of Resources 41

populations with limited dispersal abilities may potentially become genetically and spatially isolated. 

Another threat to the sustainability of wetland and 

riparian habitat in the SLVCA is the chronic overuse 

of ground water. In 2004, the Colorado Legislature 

directed the State Engineer to develop ground water 

rules and regulations for the San Luis Valley to bring 

use to sustainable levels and protect senior surface 

water users. The complicated and contentious process of developing and carrying out regulations is well 

underway. However, there have been delays because 

of court challenges and daunting technical hurdles in 

developing the ground water model that will be used 

to quantify depletions to individual streams caused by 

ground water use throughout the valley. 

Ground water usage, especially artesian well 

development, started during the early 1900s. The 

result has been construction of more than 7,000 wells 

and development of one of the world’s largest concentration of center pivot irrigation systems, many of which 

depend solely upon ground water. As a consequence, 

water users and regulators have acknowledged that 

annual ground water use during a period of belowaverage precipitation exceeds recharge. It is important to note that in addition to traditional agricultural 

irrigation, the existing national wildlife refuges in the 

San Luis Valley also use ground water adjudicated for 

both wildlife and irrigation extensively for irrigation 

and impoundments to create wildlife habitat. Ways to 

reduce reliance on ground water are being explored 

in the planning process for the comprehensive conservation plan for the San Luis Valley National Wildlife 

Refuge Complex. 

CULTURAL RESOURCES

The SLVCA is considered an important area for 

cultural resources because of the abundance of cultural sites that date to almost 12,000 years ago that 

are located throughout the valley. However, much of 

the archaeological research associated with the San 

Luis Valley has been conducted on public lands, such 

as the Closed Basin, San Juan National Forest, and 

Great Sand Dunes National Park and Preserve (Jones 

2000). Permanent protection of wildlife habitat on 

private land will benefit the preservation of cultural 

sites from future disturbance on all acquired lands.

CLIMATE CHANGE

Climate change has quickly moved to the forefront 

of conservation challenges during the 21st century, and 

the Service has made it a high priority in conservation 

planning (USFWS 2010b). Mountain ecosystems in the 

western United States are expected to be especially 

sensitive to climate change. In fact, data show that 

many places in the Rocky Mountains have experienced 

three times the global average temperature increase 

over the past century. Measurements have shown that 

Colorado’s temperature has increased by approximately 

2  ̊F between 1977 and 2006 (Ray et al. 2008). The 

western United States has seen a shift toward earlier 

spring snowmelt (Karl et al. 2009). The Rio Grande 

Basin is predicted to experience significantly warmer 

temperatures, decreasing snowpack, earlier runoff, 

increased intensity of droughts and floods, and an 

overall decrease in water availability (Bureau of Reclamation 2013).

Wetland and riparian habitats, such as those found 

in the SLVCA, that are dependent on snowmelt from 

surrounding high mountain ecosystems are expected 

to be more acutely affected than other ecosystems. The 

San Luis Valley is predicted to have a 10- to 20-percent 

reduction in runoff by midcentury compared to the 

1900 to 1970 baseline (Karl et al. 2009). As with many 

areas across the West, it is difficult to predict what the 

specific effects of climate change may be in a given 

area, particularly because of the complex interplay 

between the timing of temperature change and precipitation. The Western Water Assessment predicted that 

Colorado’s ecosystems will be affected by climate change 

in nine broad ways: increased frequency and severity 

of forest-insect interactions; increased frequency 

and severity of wildfires; changes in the hydrologic 

cycle that affect aquatic species, including reduction 

in overall streamflow, shift to earlier spring runoff, 

and warming of water temperatures; northward and 

upward shift in animal ranges, causing shifts in ecosystem composition; increased range and spread of 

wildlife pathogens; increase in tree mortality because 

of drought stress; increased risk of desertification in 

dryland ecosystems; and an overall reduction in biodiversity because of the above impacts (Averyt et al. 

2011). We must be cognizant of the potential impacts 

that climate change may have on wetland, riparian, 

and upland habitat in the SLVCA. 

The SLVCA intends to support and restore habitat 

connectivity to promote San Luis Valley and Southern 

Rockies ecosystems that will be robust in the face of 

climate change. Protection of large intact expanses of 

wetland habitat types where natural ecosystem processes can be sustained will help wetland-dependent 

species resist some of the impacts of a changing climate. 

Some of these may not be the same type of wetland 

in the future, but the use of hydrogeomorphic modeling to assess historical hydrology should allow us to 

predict where and what kind of wetlands will persist 

in a potentially warmer and more arid future. We will 

respond by targeting these habitats for acquisition in 

the SLVCA. Besides intrinsically providing habitat for 

wildlife, riparian areas also serve as corridors, as do 

the montane forests along the flanks of the surrounding 

mountains. Protection of such corridors will preserve 

a network through which wildlife can recolonize or 
42 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

disperse following disturbance, making the ecosystem 

more resilient to short-term change and increasing its 

adaptive capacity to long-term change.

Effects on the Natural and 

Human Environment

For a thorough discussion of the effects of the 

easement program, see the EA (appendix A) in this 

volume. Effects of the land protection strategy discussed in this volume are analyzed as alternative B 

in the EA (appendix A).
Chapter 4—Project Implementation

Willows and cottonwood trees line a streamside at the base of the San Juan Mountains in Colorado.

© Joe Zinn

Land Protection Choices

The following summarizes the two alternatives in 

the EA (appendix A) that led to the Service’s approval 

of the SLVCA land protection project.

NO ACTION

Under the no-action alternative, the areas outside 

of existing protected areas would largely remain in 

private ownership and subject to changes in land use 

and land cover. Some protection in addition to the 

SLVCA is likely because of ongoing conservation 

easement initiatives in the San Luis Valley by public 

entities such as NRCS and nongovernmental organizations such as Rio Grande Headwaters Land Trust 

and Colorado Open Lands. 

CONSERVATION EASEMENTS AND LIMITED FEETITLE ACQUISITION (PREFERRED ALTERNATIVE)

It is the Service’s policy to acquire the minimum 

interest in a property necessary to accomplish its 

conservation objectives. It can be possible to achieve 

most of these objectives with conservation easements. 

The preservation of working landscapes such as farms 

and rangeland is more cost effective, socially acceptable, and politically popular than acquiring fee-title 

land, and it often promotes the preservation of unfragmented, quality habitat. Under this project, the 

Service and potential partners will protect through 

conservation easements up to 250,000 acres to address 

habitat priorities described in this plan.

There are instances when the management and 

objectives of the three refuges in the San Luis Valley refuge complex may be simplified with small-scale 

acquisitions, but not with conservation easements. In 

such circumstances (for example, boundary simplification or surface water rights acquisition for an existing 

refuge), the Service will consider the acquisition of up 

to a total of 30,000 acres of fee title under the SLVCA. 

This acreage cap represents an estimate of the effort 

required to protect most of the first-priority habitat 

for the eight focal species described later in the document. Although this land protection plan in no way 
44 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

binds or directs other land protection organizations, if 

their efforts result in protection of the same habitats 

identified in this plan, our efforts may be correspondingly reduced.

Project Objectives and 

Actions

The SLVCA sits in the San Luis Valley of central southern Colorado and northern New Mexico. 

The project area contains land in Alamosa, Conejos, 

Costilla, Hinsdale, Mineral, Rio Grande, and Saguache 

Counties in Colorado, as well as a small portion of 

Rio Arriba and Taos Counties in New Mexico. The 

SLVCA boundary approximates the headwaters and 

upper watershed of the upper Rio Grande. Within the 

project boundary, the Service will strategically identify and acquire from willing sellers an appropriate 

interest in upland, wetland, and riparian habitats on 

privately owned lands.

The Service plans to buy or receive donated conservation easements or fee-title lands on identified areas 

within the project boundaries. These easements and 

limited fee-title acquisitions will connect and expand 

existing lands under public and private conservation 

protection. Based on the area of privately held priority 

habitat and the amount protected by other organizations in the San Luis Valley, the SLVCA will protect 

up to 250,000 acres of uplands, wetlands, and riparian 

areas through easements and up to 30,000 acres 

through fee title.

COLLABORATION WITH LAND PROTECTION 

ORGANIZATIONS

The San Luis Valley is fortunate to have many 

active land conservation organizations. Although 

the mission of each organization may be unique, they 

all share many common objectives. In general, the 

Service’s goal is protecting land with priority habitat 

from development and, in some cases, preventing 

water transfer when that water is supporting valuable 

habitat. We recognize that other organizations are doing 

the same thing with the same result, at times on land 

supporting important habitat for focal species identified in this plan. Our intent is to participate in land 

protection in the San Luis Valley as a partner, simply 

adding capacity to the collective effort to protect 

these habitats.

We met twice with the following organizations to 

discuss joint collaboration on the land protection plan:

■ Trust for Public Land

■ The Nature Conservancy

■ Natural Resources Conservation Service

■ Rio Grande Water Conservation District 

■ Colorado Cattlemen’s Agricultural Land Trust

■ Rio Grande Headwaters Land Trust

■ Colorado Open Lands

We are excited to work with these and other entities 

interested in the objectives of the land protection plan. 

We are committed to institutionalizing a process that 

provides a suite of options for landowners and that 

results in easements being held by the most appropriate 

organization to meet specific circumstances. For 

example, concern has been expressed that Service-held 

easements may potentially interfere with the ability of 

the Rio Grande Water Conservation District to meet 

mitigation requirements of the habitat conservation plan 

for the southwestern willow flycatcher. This is a valid 

concern since the only conservation easements that can 

be credited to mitigation goals are those funded from 

non-Federal sources. Such conflict would be counterproductive for endangered species conservation. It is 

clear that land conservation in potential southwestern 

willow flycatcher habitat would need to be carried out 

in coordination with other conservation parties.

EASEMENT TERMS AND REQUIREMENTS

The Service has successfully carried out easements 

in many projects, and existing language and guidelines will contribute substantially to the drafting of 

the SLVCA easement language. Given the Service’s 

conservation goals in the SLVCA, the easements will 

be drafted with standard language to preclude subdivision and development and conversion of native 

vegetation to cropland, as well as to protect existing 

wetlands from being drained or filled. 

In addition, because of the scarcity of water resources 

in the valley and impending changes to ground water 

law in the State of Colorado, there may be provisions 

about water use. The types of wetland and associated 

upland habitats in which we are interested are largely 

supported by current water use practices. Easements 

may include a stipulation that any sale of water cannot 

adversely affect the quality of habitats that we seek to 

protect in the easements, and that water rights now 

owned for use on a property under an easement cannot be sold or transferred for use on other properties 

unless such a transfer was deemed beneficial to wildlife. These will be new easement terms for the Service 

and require further investigation before they can be 

carried out as part of the SLVCA program.

The protection of riparian corridors is important in 

the SLVCA, particularly because much of the lower 

elevation habitat has, or has the potential to have, 

the constituent elements of critical habitat for the 
Chapter 4—Project Implementation 45

southwestern willow flycatcher1. While easement language will not prescribe specific management practices 

on these lands, landowners with suitable or potentially 

suitable riparian habitat will be encouraged to work 

with the Partners for Fish and Wildlife Program or 

the new Working Lands for Wildlife Program (NRCS 

2012) to develop alternative strategies such as fencing 

of riparian corridors and off-river stock watering to best 

manage grazing of regenerating riparian vegetation. 

CONTAMINANTS OR HAZARDOUS MATERIALS

Level 1 pre-acquisition site assessments will be 

conducted on individual tracts before the purchase 

of any land interests. The Service’s environmental 

contaminants specialists from the Ecological Services 

offices in Colorado and New Mexico will be contacted 

to make sure that policies and guidelines are followed 

before acquisition of conservation easements or fee title.

ACQUISITION MONEY

The Service will acquire easements in the SLVCA 

primarily through Land and Water Conservation Fund 

monies. These monies are derived primarily through 

revenue generated from oil and gas leases on the Outer 

Continental Shelf, motorboat fuel taxes, and the sale 

of surplus Federal property. These monies are not 

derived from general taxes. While Land and Water 

Conservation Fund monies are intended for land and 

water conservation projects, payment is subject to 

annual appropriations by the U.S. Congress for specific 

acquisition projects. If it is reauthorized by the U.S. 

Congress, the Federal Land Transaction Facilitation 

Act could also be used to pay for specific acquisitions. 

This act is a law that allows the BLM to dispose of 

certain public lands to generate revenue for strategic conservation of habitat not now in Federal trust.

The SLVCA project area has several other government and nongovernmental organizations with overlapping conservation objectives. In the development of the 

SLVCA, land for acquisition has been ranked by the 

Service, but the LPP may also guide acquisitions for 

conservation by the NRCS Wetland Reserve Program, 

The Nature Conservancy, Colorado Open Lands, and 

the Rio Grande Headwaters Land Trust, among others. 

Incorporating Science 

and Strategic Habitat 

Conservation in the SLVCA

The Service uses the best available science to help 

figure out which areas are appropriate to consider adding 

1

FR 76(157), 50542–629. Endangered and Threatened Wildlife and 

Plants; Designation of Revised Critical Habitat for Southwestern 

Willow Flycatcher. Agency: U.S. Fish and Wildlife Service. Action: 

Proposed Rule. August 15, 2011

to the National Wildlife Refuge System. Continuing 

to look at the resources and objectives and gathering 

more data will help us be strategic in ongoing and 

future conservation efforts.

STRATEGIC GROWTH OF THE NATIONAL WILDLIFE 

REFUGE SYSTEM

The SLVCA encompasses approximately 4.2 million acres in a region where demand for conservation 

easements already far exceeds available funding. Given 

the likelihood that there may be more land available 

for conservation easements than appropriated funding, it is important to ensure that the money that is 

available is spent in a way that maximizes returns 

for trust species or helps ensure the connectivity, 

resiliency, and long-term function of the ecosystems in 

the project area, or both. In recognition of the limited 

resources available for land protection, the National 

Wildlife Refuge System is narrowing our focus to 

acquiring interests in land that contributes to the goals 

of one or more of the following national conservation 

objectives. We describe our contribution to these 

objectives below.

Aid in the Recovery of Threatened and 

Endangered Species

The SLVCA provides habitat for six listed species 

(southwestern willow flycatcher, Mexican spotted owl, 

and Canada lynx, Gunnison sage-grouse, yellow-billed 

cuckoo, and New Mexico meadow jumping mouse).

A section 7 biological evaluation for federally listed 

species found that the actions of the SLVCA “may 

affect but [are] not likely to adversely affect” listed 

species or designated critical habitat (appendix E). 

Descriptions of several of these species follow.

Southwestern Willow Flycatcher. This is a genetically 

distinct subspecies (Paxton 2000) of willow flycatcher 

that inhabits the woody riparian corridors of the desert 

southwest. Its population has declined significantly 

because of habitat loss, and it is listed as endangered 

by the States of Colorado and New Mexico as well 

as under the Federal Endangered Species Act. The 

recovery plan for the southwestern willow flycatcher 

specifically lists conservation easements and land 

acquisition as ways to implement recovery criterion 2: 

“Provide protection and create/secure sufficient habitat to assure maintenance of these populations and/or 

habitats over time.” The recovery plan also identifies 

segments of the Rio Grande and Conejos River within 

the project area as having substantial recovery value 

(USFWS 2002). As of 2009, there were 15,128 acres 

of woody (willow- or cottonwood-dominated) riparian 

vegetation in the San Luis Valley (ERO 2012). Of 

these, approximately 11,475 acres are on unprotected 

private lands within the SLVCA boundary. Many of 

these acres are in very small, scattered parcels and 
46 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

may not be suitable for hosting breeding birds, but 

there is documentation of willow flycatchers on the 

Rio Grande breeding in patch sizes as small as 0.25 

acre (Cooper 1997, as cited in USFWS 2002). Using 

the estimate of 11 acres per territory that was used in 

the Service’s Biological Opinion for the San Luis Valley 

Regional Habitat Conservation Plan (ERO 2012), it 

is likely that the SLVCA could help conserve habitat 

for several dozen more pairs of flycatchers in addition 

to the 68 pairs known as of 2005 (T. Ireland, U.S. Fish 

and Wildlife Service, personal communication, March 

2013). This could substantially enhance the redundancy 

of breeding pairs in the San Luis Valley management 

unit of the Rio Grande recovery unit, which requires 

a minimum number of 50 territories for downlisting.

Canada Lynx. The lynx is federally listed as threatened and State-listed in Colorado as endangered. 

Canada lynx range through the montane forests of 

the Rocky Mountains. They are resident in the San 

Juan and Sangre de Cristo Mountains, and the junction between the Sangre de Cristo Range and the 

Culebra Range of the Sangre de Cristo Mountains has 

been identified as a particularly important corridor 

for the species (L. Ellwood, the Service’s Ecological 

Services Colorado Field Office, personal communication, 

January 2012). This land falls within the adjoining 

SCCA. Within the SLVCA, the vast majority of lynx 

habitat is already protected, largely in Rio Grande, 

San Isabel, and Carson National Forests. However, 

the Canada lynx could benefit from the SLVCA, 

particularly from protection of the willow riparian 

corridors that the lynx prefer (Mowat and Slough 

2003), which also surround the habitat of the Rio 

Grande cutthroat trout.

Gunnison Sage-Grouse. The sage-grouse has been 

listed as threatened, wherever it is found, primarily 

due to “habitat loss, degradation, and fragmentation 

due to residential, exurban, and commercial development and associated infrastructure such as roads and 

power lines” (USFWS 2013c). These are precisely the 

threats that the SLVCA’s conservation easement program is designed to counter. The smallest of the existing sage-grouse populations is found in the sagebrush 

habitat on the south side of Poncha Pass at the far 

northern end of the SLVCA. Although the area was 

originally proposed as critical habitat for this population which covers 48,292 acres, of which 15,921 acres 

are unprotected private lands (USFWS 2013b), it was 

not included in the final critical habitat designation 

because of concerns that this small population may 

need to be augmented by translocation or release of 

captive-reared birds to be sustainable (USFWS 2013b). 

Nonetheless, both occupied and adjacent suitable but 

unoccupied habitat in the SLVCA could be protected 

under this plan, in part due to the high landowner 

support in this portion of the project area.

Yellow-billed Cuckoo. The San Luis Valley Regional 

Habitat Conservation Plan and its associated woody 

riparian vegetation mapping also inform estimates of 

the SLVCA’s potential conservation benefits to the 

federally threatened yellow-billed cuckoo. Cuckoos 

breed in cottonwood-dominated riparian forest and 

occupy territories that average 54.4 acres in size. The 

extent of breeding by yellow-billed cuckoos in the San 

Luis Valley has not been well documented, but the 

birds have been observed along the Conejos River 

and Rio Grande. Of the 10,019 acres of cottonwooddominated riparian forest in the valley, 8,239 acres 

is on unprotected private lands within the SLVCA 

boundary. There are seven patches greater than 54.4 

acres, which could host at least 10 pairs of cuckoos. 

New Mexico Meadow Jumping Mouse. Listed 

as endangered under the Endangered Species 

Act, the New Mexico meadow jumping mouse is a 

strongly genetically divergent lineage (King et al. 

2006) of the more widespread meadow jumping mouse 

that inhabits the southwestern United States. The 

mouse prefers riparian habitat and requires permanent free-flowing water (Morrison 1990). Poor grazing 

management is one of the mouse’s primary stressors, 

although drought, development, and other factors are 

influencing its decline (Frey and Malaney 2009). The 

presence of the New Mexico meadow jumping mouse 

in the SLVCA is unknown, but it was historically found 

along the Rio Grande and in the Jemez and Sangre 

de Cristo Mountains just south of the project area 

(Morrison 1992). Because the SLVCA is at the northern 

boundary of the mouse’s range, we performed a cursory analysis of its potential for range expansion in 

the project area using the correlative environmental 

niche modeling technique implemented in Maxent 

(Phillips et al. 2006). A thorough overview of this 

method is beyond the scope of this plan, but essentially the program uses known locality data (species 

occurrence records from museum specimens) and 

candidate correlative variables (in this case, 30-arc-second 

resolution bioclimatic data) to define the probability 

of the species’ occurrence across the landscape. This 

was then graphically displayed as a map of the species’ 

potential range. It is important to recognize that this 

method does not account for physical factors (such as 

mountains that prevent dispersal to suitable habitat) 

or ecological factors (like similar species already occupying the same niche) that constrain the species’ actual 

distribution; nor does the model account for the mouse’s 

restrictive habitat requirements. The resulting model 

was then used to forecast the potential distribution of 

the mouse under climate change, specifically in an A2 

emissions scenario in the year 2080 (www.worldclim.org

/download). It is apparent from figure 4 that the New 

Mexico meadow jumping mouse may undergo both 

expansion and contraction of in different portions of 
Chapter 4—Project Implementation 47

Figure 4. Spatial graphic of predicted distribution of the New Mexico meadow jumping 

mouse in the 20th century (top) and the late 21st century (bottom) in the San Luis Valley 

Conservation Area, Colorado and New Mexico.

(Note the contraction of its southern range and expansion into a more northern distribution.)
48 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

its range, and most relevant to the SLVCA, it has the 

potential to expand into the riparian corridors of the 

San Juan and northern Sangre de Cristo Mountains 

within the SLVCA boundary. Protection of riparian 

habitats in this region could give the species the 

adaptive capacity to persist in the face of likely range 

contractions in more southerly portions of its range.

Rio Grande Cutthroat Trout. Recently removed as 

a candidate species under the Endangered Species Act, 

the Rio Grande cutthroat trout is primarily threatened 

by introduction of nonnative trout. However, these 

trout are also susceptible in their present range to anthropogenic habitat disturbance due to things such as 

“grazing, logging, mining, road construction, and water 

extraction” (Pritchard and Cowley 2006). Some of 

these disturbances, such as construction, could be 

reduced or prevented on streams that cross properties with SLVCA conservation easements. Of the approximately 168 miles of designated “conservation 

population” (managed for less than 10-percent genetic 

introgression from other trout) stream segments in 

the SLVCA, just over 50 miles are on private lands 

without protection. These stream segments range 

from less than 50 fish per mile to more than 400 fish 

per mile (USFWS 2008b), so minimization of disturbance in these watersheds could protect significant 

numbers of these fish. 

Conserve Migratory Birds in Decline

The San Luis Valley hosts 32 species which were 

identified as declining or of conservation concern 

by staff of the Region 6 Migratory Birds Program 

(table 4). Of these species, the Partners in Flight North 

American Landbird Conservation Plan identifies the 

following species’ considerations:

■ Gunnison sage-grouse is a watch list species with 

multiple causes for concern across it entire range.

■ Swainson’s hawk, short-eared owl, olive-sided 

flycatcher, and willow flycatcher are watch list species that are moderately abundant or widespread 

with declines or high threats.

■ Lewis’ woodpecker is a watch list species because 

of its restricted distribution or low population size.

■ Sage thrasher and Williamson’s sapsucker are 

“Additional Stewardship Species” because a high 

percent of their global populations occur in a single 

biome (Rich et al. 2004). 

For those species with a significant portion of their 

global population in the Intermountain West biome 

(which contains the project area), estimates of the 

proportion of their breeding and wintering populations are provided in table 4.

Consistent monitoring is essential for assessing whether we are being successful in meeting our conservation objectives, 

particularly in a dynamic environment.

© Joe Zinn
Chapter 4—Project Implementation 49

Table 4. Resident, migratory, and breeding birds of concern within the San Luis Valley Conservation Area, Colorado 

and New Mexico, with their status and objectives from a relevant continental or regional conservation plan or list.

Partners in 

Flight 

percent of global 

population in 

Colorado 

North American Landbird 

Conservation Plan 

U.S. Shorebird 

Conservation Plan

Common name

Watch list (WL) and 

stewardship (S) species 

and population objective

Percent of global breeding 

and winter population 

in Intermountain West 

avifaunal biome

Relative 

importance of 

Intermountain 

West to species 2

Conservation 

category 3

American avocet B, M, W 3

American bittern1,a,b

Baird’s sandpiper M 2

Black-bellied plover M, W 3

Black-headed grosbeak1 3.2

Black-necked stilt B, M, W 2

Cinnamon teal1, b

Cordilleran flycatcher1 14.6

Greater yellowlegs M, W 3

Gunnison sage-grouse1, a WL, increase 100% 100/100

House wren1 2.2

Least sandpiper M, W 3

Lesser yellowlegs M, w 3

Lewis’s woodpecker1,a,b 16.1 WL, maintain/increase 87/52

Long-billed curlewa,b,c B, M, W 5

Long-billed dowitcher M, W 2

Marbled godwitb,c B, M, W 4

Northern goshawk1,a 0.9

Olive-sided flycatcher1,a,b 1.8 WL, increase 100% 21/0

Pectoral sandpipera m 2

Sage thrasher1,b 5.7 S, maintain 99/31

Sanderling m 4

Semipalmated plover M, w 3

Short-billed dowitcherb m 4

Short-eared owl1,a,b WL, increase 100%

Snowy plovera,b,c B, M, W 5

Solitary sandpiperb m 4

Stilt sandpipera m 3

Swainson’s hawk1,a,b 9.8 WL, maintain/increase 15/0

Warbling vireo1 4.4

Western sandpiper M, W 4

Willet B, M, W 3

Williamson’s sapsucker1,a,b 9.3 S, maintain 94/15

Willow flycatcher1,a,b 0.7 WL, increase 50%

Wilson’s phalarope B, M 4

a Colorado Species of Greatest Conservation Need, Tier 1 and 2 (CPW 2015)

b Service’s Region 6 Bird of Conservation Concern (FWS 2008c).

c Service’s Migratory Bird Program focal species (FWS 2015).

1 Known to breed in the San Luis Valley Conservation Area.

2 B=breeding, M=migration, W=wintering: common or locally abundant, region important to the species.

 B=breeding, M=migration, W=wintering: high concentration, region extremely important to the species relative to the majority of other regions.

 b=breeding, m=migration, w=wintering: uncommon to fairly common, region within species range but occurs in low relative abundance 

 relative to other regions.

3 Low (1) to high (5) priority.
50 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

The U.S. Shorebird Plan identifies the Intermountain 

West region, of which the SLVCA is part, as important 

for several species of shorebird. For example, some 90 

percent of the world’s adult Wilson’s phalaropes stage 

in the Intermountain West during migration, many 

of them in the San Luis Valley. The biggest threat to 

shorebirds in this region is human-driven competition 

for water, which is why the preservation of wetlands 

is a primary focus of this project. The importance of 

the region to these species, as well as their conservation category, is shown in table 4. 

Implement the North American Waterfowl 

Management Plan

While there are certainly many species of waterfowl 

that use the San Luis Valley for breeding, wintering, 

or migration, none of them do so in numbers significant 

at a continental scale. However, there is a regionally 

significant breeding population of cinnamon teal in 

the project area, and these are identified as a priority species by the Intermountain West Joint Venture.

STRATEGIC HABITAT CONSERVATION

To ensure that our efforts to deliver conservation 

are effective, the SLVCA will incorporate the elements 

of strategic habitat conservation. Strategic habitat 

conservation is based on an adaptive management 

framework and entails starting with strategic conservation planning, followed by conservation design, 

conservation delivery, and monitoring and research 

to assess results.

Strategic Biological Planning

Biological planning requires the identification of 

specific biological objectives or focal species so that 

the relative success of a strategy can be assessed 

following implementation. The focal species identified to guide prioritization of the SLVCA were chosen 

because of the Service’s obligations to them as Federal trust species (candidate, threatened, and endangered species and migratory birds). Another factor is 

that the land protection undertaken to benefit focal 

species is likely to have conservation benefits for other 

species of conservation concern, such as species that 

are federally or State-listed as threatened or endangered, the Service’s Region 6 birds of conservation 

concern, and the Service’s migratory bird focal species. For example, protection of cottonwood riparian 

habitat for Lewis’ woodpecker, a conspicuous regional 

bird of conservation concern, may also protect habitat for the more elusive yellow-billed cuckoo, recently 

listed as threatened under the Endangered Species 

Act. Because of a lack of systematic nesting surveys 

for these species in the project area, assumptions were 

made based on scientific literature and expert opinion 

regarding which types of habitat were important for 

maintaining viable populations of the focal species. In 

particular, given the limited amount of quality wetland 

and riparian habitat present compared to presettlement conditions, it was assumed that the continued 

presence of those riparian types was a limiting resource in the life history of species that are thought 

to be obligate breeders in such habitat. 

These focal species were chosen with the knowledge that there are gaps in existing data and that the 

habitat in the project area is likely to evolve over time 

in the face of environmental change and changes in 

human water use. As new data become available or 

as conditions change to the point that this conservation strategy is no longer effective, biological planning 

will be revisited.

Conservation Design and Delivery

Preventing loss of habitats identified for the diverse 

suite of focal species is the goal of the prioritization 

scheme outlined in section 4.4. Decisions about how to 

rank competing parcels with limited available funds 

will follow the outline described in that section. 

The recovery plan for southwestern willow flycatcher requires a minimum of 50 occupied breeding 

territories in the San Luis Valley (USFWS 2002), and 

specific reaches of the Rio Grande were identified as 

critical habitat to maintain that level (USFWS 2013a). 

As previously discussed, this habitat will be granted 

high priority for land protection. Some of these reaches 

have poor or nonexistent habitat but were included in 

the designation due to their potential and proximity 

to known concentrations of southwestern willow flycatchers. All easement opportunities within the priority lands for southwestern willow flycatcher should be 

considered in the interest of providing redundancy to 

currently occupied habitat, even if the priority lands 

are unoccupied.

In the absence of specific population goals for the 

remaining focal species, no population targets or breeding pair densities have been selected. Following the 

principle that between 25 and 75 percent of a region 

must be conserved to meet targets for biodiversity 

(Noss et al. 2012), the initial targets for easement 

acquisition are to protect 50 percent of existing priority 

habitat for these focal species. As survey data for 

the valley informs the role of the SLVCA in meeting 

specific regional or continental population objectives 

for other species, the acquisition of easements and 

limited lands in fee title can be adjusted accordingly.

Monitoring and Research

Essential to the success of strategic habitat conservation is an effective monitoring program to ensure 

that conservation delivery is resulting in net positive 

benefits for the focal species around which the project 

was designed. While the consensus conservation model 

is primarily meant to guide effective easement acquisition, the individual species maps are intended to 
Chapter 4—Project Implementation 51

guide conservation delivery for those species. Monitoring of populations will help ensure the efficacy of 

the program. If negative population trends for those 

species are detected within the project area or at a 

regional or continental scale, then further literature 

review or targeted research, or both, can be applied 

to adjust conservation planning for the SLVCA. 

Some of the monitoring phase of strategic habitat 

conservation can be carried out using the capacity 

of the refuge biologist and Service’s Inventory and 

Monitoring assistance. However, it is important to 

recognize that similar monitoring will be carried out 

by partner agencies, and communication among these 

agencies is crucial for effective monitoring in the face 

of limited personnel and financial resources. Further, 

Service staff should leverage biological expertise at 

regional academic institutions to facilitate basic and 

applied research while addressing research gaps as 

they are identified. 

Specifically, monitoring and research should include 

the following:

■ Developing, improving, and assessing landscape 

models for focal species. Emphasis will be placed 

on the highest priority species with the greatest 

degree of uncertainty regarding limiting factors 

and the effectiveness of management actions, 

including acquisition under the SLVCA program, 

at minimizing and reducing the limiting factors for 

those species. Data from existing surveys such as 

Breeding Bird Survey routes in the project area will 

be evaluated and incorporated into spatial models. 

When necessary, additional data will be collected 

to evaluate assumptions used in the modeling process and assessments will be adjusted accordingly. 

These methods will provide an estimate of the population response of trust species on easement lands 

and on noneasement properties. Similar modeling 

approaches may be developed or incorporated for 

priority nontrust species in cooperation with partners 

such as State wildlife agencies, nongovernmental 

organizations, and universities.

■ Evaluating assumptions and addressing uncertainties identified through the biological planning, 

conservation design, and conservation delivery 

elements. When warranted, the Service will evaluate assumptions such as increased redundancy of 

occupied southwestern willow flycatcher habitat 

through protection of riparian vegetation.

■ Identifying appropriate population goals for focal 

species and assessing the contribution of land protection toward meeting the population goals. This 

will allow the Service and conservation partners to 

evaluate the contribution of the program to meeting 

the population goals and to refine conservation 

delivery to ensure maximum effectiveness. 

■ Determining how changing environmental conditions may influence the effectiveness of this 

conservation design. The Service will look at how 

increased evapotranspiration, social and economically driven changes in water use, and evolution 

of the type and timing of precipitation and runoff 

influence the hydrology of the SLVCA.

Protection Priorities

The Service, in consultation with internal divisions 

(Migratory Birds, Fisheries, Ecological Services), 

nongovernmental organization partners, Colorado 

Parks and Wildlife, and BLM, selected eight focal species whose habitat needs have driven the prioritization within the SLVCA. Each of these focal species 

represents a group of species that are vulnerable to 

the same threat processes (Lambeck 1997):

■ Canada lynx

■ Rio Grande cutthroat trout

■ Southwestern willow flycatcher

■ Lewis’ woodpecker

■ Wilson’s phalarope

■ American bittern

■ Gunnison sage-grouse

■ sage thrasher

All of these are Federal trust species or have State 

or regional conservation status, or both, making them 

worthy of protection on their own. However, conserving habitat for these species will also protect habitat 

for other species with similar habitat requirements.

SPECIES-HABITAT MAPPING METHODOLOGY

Some of the chosen species, by virtue of their having 

special conservation status, had already been the subject of detailed habitat mapping in the project area. 

For others, simple conceptual models were developed 

based on literature reviews.

The willow and cottonwood riparian habitats necessary for southwestern willow flycatcher breeding 

in the San Luis Valley have been mapped in detail as 

part of the development of the San Luis Valley Habitat 

Conservation Plan for that species (ERO Resources, 

unpublished data). The data also capture the mature 

cottonwood habitat needed for both the Lewis’ woodpecker in this portion of its range and for the breeding 

habitat of the yellow-billed cuckoo. The existing data 

were used to define core habitat in this prioritization 
52 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 5. Map of southwestern willow flycatcher and Canada lynx habitat in the San Luis Valley Conservation Area, Colorado and New Mexico.
Chapter 4—Project Implementation 53

Protection of habitat for Federal trust species would also 

ensure connectivity for State-managed species such as 

the American black bear.

Steve Torbit / USFWS

scheme; as a second priority, a 656-foot (200-meter) 

buffer was used to minimize disturbance of the core 

habitat (Terry Ireland, the Service’s Ecological Services, personal communication, February 2012). These 

priorities are illustrated in figure 5. 

Canada lynx habitat in the project area has already 

been mapped by Colorado Parks and Wildlife and the 

U.S. Forest Service. A small portion of the project 

area in northern New Mexico had not been covered by 

previous mapping but is known to be actively used by 

lynx. Therefore, a minimum convex polygon for this 

region was created that captured the land cover that 

largely comprises the Colorado Parks and Wildlife 

habitat (Rocky Mountain aspen forest and woodland, 

Rocky Mountain lodgepole pine forest, Southern 

Rocky Mountain mesic montane mixed conifer forest 

and woodland, and Rocky Mountain subalpine drymesic spruce-fir forest and woodland) using 98-foot 

(30-meter) Landfire data (USGS 2010). Lynx habitat 

is identified in figure 5.

The habitat of the Endangered Species Act candidate Rio Grande cutthroat trout has been mapped 

throughout the species’ range; in addition, information on barriers to fish passage and data on genetic 

integrity has incorporated into a spatial database. 

Because interbreeding has been a problem for cutthroat trout species, the signatory parties to the 2009 

Rio Grande Cutthroat Trout Conservation Agreement identified populations with less than 10-percent 

genetic introgression and defined them as conservation 

populations (Rio Grande Cutthroat Trout Conservation Team 2009). These conservation populations were 

chosen as representing priority habitat for the species 

in this land protection plan (figure 6). 

The range of the Gunnison sage-grouse is much 

more geographically limited than it once was. The 

Gunnison Sage-Grouse Steering Committee revised 

early, coarse-scale, historical range mapping for the 

species (Schroeder et al. 2004) and identified current 

and suitable but unoccupied habitat (Gunnison Sagegrouse Rangewide Steering Committee 2005). In the 

project area, there is a small lek at Poncha Pass and 

some adjacent suitable but unoccupied habitat. Current range polygons were selected to represent priority habitat for this species; the historical range is also 

displayed for reference (figure 7). 

The San Luis Valley represents a regionally 

important breeding habitat for the Wilson’s phalarope (Scott Miller, San Luis Valley Refuge Complex, 

personal communication, January 2012) as well as habitat for many other species of migratory shorebirds. 

Because an applicable statistical or conceptual model 

for migratory shorebird breeding in the Southern 

Rockies was unavailable, a conceptual model based 

on published habitat associations of Wilson’s phalarope was developed. A study of waterbird nesting in 

the San Luis Valley found that phalaropes preferred 

seasonal and short-emergent wetlands, probably 

because these habitats have the highest invertebrate 

biomass of the habitats available to them (Laubhan 

and Gammonley 2000). Wetlands classified by the 

National Wetland Inventory as temporary and seasonal 

were given the highest priority, followed by areas of 

saturated soils, as these wetland classes most closely 

match the definitions of seasonal and short emergent. 

Because Wilson’s phalaropes are known to be sensitive 

to encroachment by woody vegetation (Cunningham 

and Johnson 2006), wetlands in the first and second 

priority classes were downgraded to third priority if 

they occurred within 328 feet (100 meters) of woody 

vegetation. In Colorado, Wilson’s phalaropes typically 

breed in intermountain valleys between 7,000 and 

10,000 feet (Kingsley 1998); however, the Service’s 

Migratory Birds staff believe that most breeding 

likely occurs below 8,000 feet (S. Jones, the Service’s 

Migratory Birds, personal communication, February 

24, 2012), and so more conservative criteria were used 

for characterizing important phalarope habitat in the 

SLVCA (figure 8). 

The secretive American bittern is an important 

representative species for a suite of waterbirds in 

the project area. Like the Wilson’s phalarope, neither 

San Luis Valley–specific habitat mapping nor applicable modeling from elsewhere were available. A review of American bittern biology demonstrates that 

the species will nest in a wide variety of wetland and 
54 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 6. Map of Rio Grande cutthroat trout habitat in the San Luis Valley Conservation Area, Colorado and New Mexico.Conservation populations are those stream reaches with Rio Grande cutthroat trout that have less than 10-percent genetic introgression from other species. Barriers indicate impediments to upstream movement, many of which prevent invasion by nonnative fish.
Chapter 4—Project Implementation 55 Figure 7. Map of present Gunnison sage-grouse habitat in and around the San Luis Valley Conservation Area, Colorado and New Mexico, with historical range indicated for reference.
56 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 8. Map of Wilson’s phalarope habitat in the San Luis Valley Conservation Area, Colorado and New Mexico.
Chapter 4—Project Implementation 57

associated upland types (Dechant et al. 2004). However, 

research has consistently shown a preference for tall, 

dense cover (Duebbert and Lokemoen 1977, Riffell et 

al. 2001), particularly bulrush- and cattail-dominated 

wetlands (Azure 1998; Bent 1963; Brininger 1996; 

Faanes 1981, as cited in Dechant et al. 2004; Weber 

1978; Weber et al. 1982). Bittern are also found occasionally in wet meadows (Faanes 1981), particularly 

those with some cattails (Middleton 1949). Therefore, 

wetlands that were classified by the National Wetlands 

Inventory as permanent, semipermanent, or seasonal 

(those with a tall emergent vegetation component) 

were selected as the highest priority for American 

bitterns. Because bitterns are area sensitive (Brown 

and Dinsmore 1986, Riffell et al. 2001) and prefer 

wetlands of greater than 7.4 acres (3 hectares) (Daub 

1993, as cited in Dechant et al. 2004), that area was 

used as a threshold. To define first-priority wetlands, 

wetlands of these types covering less than 7.4 acres 

were assigned second priority. Temporary and saturated wetlands, which are often wet meadows, were 

designated as third priority. In Colorado, American 

bitterns are residents of marshes between 3,500 and 

8,000 feet (Bailey and Niedrach 1967), so the latter 

elevation was used to constrain bittern habitat in the 

SLVCA. These priorities are illustrated in figure 9. 

Sage thrasher is a migratory bird that has been 

declining throughout its range due to habitat loss 

and degradation, and is one of the Service’s Region 6 

birds of conservation concern as well as a migratory 

bird focal species. A rangewide conceptual model for 

the species was developed by the American Bird Conservancy based on Rocky Mountain Bird Observatory 

sampling data (Beason et al. 2005) and ReGap land 

cover data. The population estimates they assign to 

these land cover classes are further stratified based 

on the classification of vegetation quality as good, fair, 

or poor, which was in turn derived from shrub cover 

density and prevalence of invasive plants. In the 

absence of data on vegetation quality for the San Luis 

Valley, “fair” quality was selected for all land cover 

types. The model developers determined that Intermountain basins big sagebrush shrubland, Intermountain basins montane sagebrush steppe, and Colorado 

Plateau mixed low sagebrush shrubland will support, 

on average, 0.0528252 birds per acre; this group of vegetation types was selected as the first priority in the 

sage thrasher–specific map (figure 10). Intermountain 

basins mixed salt desert scrub, Intermountain basins 

greasewood flat, and Intermountain basins semidesert 

shrub steppe support 0.009348 birds per acre; these 

vegetation classes were selected as the second priority 

for the species. Within these two priority levels, only 

polygons greater than 247 acres (100 hectares) in area 

were included because sage thrasher are known to 

be somewhat area sensitive and are found most commonly in patches of that size or greater (Knick and 

Rotenberry 1995). 

LANDSCAPE PRIORITIZATION

The species-specific maps are useful for determining where in the landscape the key habitats are for 

the identified focal species. However, the maps do not 

assist decisionmakers with determining which areas 

will provide the most effective conservation returns 

overall. In addition to the presence or absence of 

habitat for individual species, it is important to take 

into account issues such as connectivity, cost, and 

unequal conservation need for each species. Therefore, the simulated-annealing algorithm implemented 

in the software package Marxan (Ball et al. 2009) was 

used to identify optimal solutions for conservation 

prioritization within the SLVCA. Marxan permits 

the user to specify individual conservation targets 

for conservation features (in this case, area of focal 

species habitat) and species-specific penalties on 

models that do not meet conservation targets. This 

allows the user to individually weight features, such as 

upweight penalties for not including enough habitat for 

species of higher conservation concern, or reduce the 

amount of land necessary for generalist widespread 

species. By designating a boundary-length modifier, 

the user can generate a more compact reserve system. 

The landscape can also be classified by cost, which can 

be made as simple as land area or more complex and 

meaningful by accounting for variables like land costs.

Because of the degree of flexibility allowed by 

Marxan, the values for these parameters need to be 

optimized by successive iterations of the program. For 

this analysis, hexagonal planning units were selected, 

as these have been shown to result in less fragmented, 

more efficient reserve networks (Nhancale and Smith 

2011). Hexagons were 49.4 acres (20 hectares) in area, 

which provides resolution that is sufficient for making 

land protection decisions while covering the SLVCA 

in few enough planning units to not be computationally overwhelming. Hexagons already in a permanent 

protected status (existing conservation easements) 

were locked in to the model and counted toward the 

targets for the individual conservation features (focal 

species). Marxan was run for 1,000 runs at 100 million 

iterations. The species-specific data were included 

as features in the Marxan model. A boundary length 

modifier of 0.0001 was used to create a slightly more 

compact reserve network. Increasing that value to 

0.001 oversimplified the reserve network and did not 

meet the intent of the SLVCA. Targets for protection 

were set at 50 percent of the land holding a particular conservation feature. Two exceptions were Rio 

Grande cutthroat trout, which was set at 75 percent 

because the linearity of its habitat promotes connectivity between existing protected areas, and Gunnison 

sage-grouse, which was set at 90 percent because of 
58 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 9. Map of American bittern habitat in the San Luis Valley Conservation Area, Colorado and New Mexico.
Chapter 4—Project Implementation 59Figure 10. Map of sage thrasher habitat in the San Luis Valley Conservation Area, Colorado and New Mexico.
60 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure 11. Map of spatial conservation prioritization within the San Luis Valley Conservation Area, Colorado and New Mexico.The relative frequency at which an individual hexagon was selected is indicated by its color, with warmer colors denoting more important locations.
Chapter 4—Project Implementation 61

its relatively small size and the high landowner support and interest in that portion of the project area. 

The frequency with which individual hexagons were 

selected in the final solution for each of the 1,000 models is shown in figure 11.

EVALUATION OF EASEMENT POTENTIAL

As described in section 4.1, acquisition of conservation easements is not a new tool for achieving conservation objectives within the SLVCA; the NRCS has 

a small number of easements, and nongovernmental 

organizations hold tens of thousands of acres of easements in the project area. These organizations have 

overlapping, but not identical missions to the Service. 

The Service currently holds only three conservation 

easements in the project area; however, we have more 

than 50 years of experience acquiring conservation 

easements in other parts of the country.

The landscape modeling described above has generated maps of species-specific conservation priorities 

for each of the focal species, as well as a consensus 

map that shows where conservation returns for 

Federal funds could be maximized for the suite of 

species examined. Biologists and realty specialists 

will work cooperatively to use these tools to identify 

parcels whose conservation will result in the greatest 

benefit to trust species. 

When a willing seller approaches the Service or 

if the Service wishes to proactively seek out sellers, 

the following criteria will guide our decisionmaking:

■ Overall Conservation Value. Is the property located, 

in whole or in part, in an area that was selected 

frequently in Marxan, as indicated by figure 11?

■ Trust Species Value. Does the parcel contain priority habitat that was identified in any of the speciesspecific maps in the previous section? 

■ Previously Unidentified Conservation Value. If 

neither of the preceding thresholds are reached, 

is there another compelling reason (for example 

securing of important water rights, promoting 

critical habitat connectivity, identification of new 

species of conservation concern, simplified management of an existing refuge unit, or donation of 

intact or easily restored habitat) that justifies the 

property’s protection?

■ Interest of Collaborators. Is there a consensus 

among collaborators that a potential easement is 

best held by a land protection organization other 

than the Service? (See “Collaboration with Land 

Protection Organizations” under “4.2 Project 

Objectives and Actions.”)

Nothing in these guidelines is intended to limit 

the appropriate exercising of discretion and professional judgment by realty specialists and refuge staff. 

Acquisition will comply with realty policy and 

potential acquisitions will be subject to scrutiny to 

determine that the habitat for which the property 

was identified as a priority is, in fact, present on the 

parcel. As mentioned in the third criterion, there may 

also be additional reasons why acquisition of interest 

in a parcel is justified, even if it did not rank highly in 

models for selected priority trust species at the time 

that this plan was approved.

Socioeconomic 

Considerations

As discussed in detail earlier, the population in 

the project area is relatively low. Much of the land is 

cropland or rangeland. Landownership patterns vary 

widely, from dense 5- to 10-acre parcel subdivisions 

to ranches of more than 90,000 acres. Some facets of 

the agricultural economy are likely to be challenged 

by new ground water augmentation laws. The potential infusion of capital from the SLVCA conservation 

easement program may provide landowners with 

resources to invest that would allow them to continue 

operation. That money will largely be invested within 

the San Luis Valley, so there will be short-term benefits 

to the local economy as well. Local governments are 

supportive of the initiative for these reasons, and 

because the program is easement based and therefore 

should not significantly affect revenues.

Because the wildlife resources for which the SLVCA 

was designed already occur in these agricultural lands, 

sustaining this cornerstone of the regional economy is 

important to the mission of the Service. Maintaining 

these working, agricultural lands will also retain the 

character that defines the San Luis Valley.

Public Involvement and 

Coordination

Public involvement is important throughout the 

planning process, including scoping before plan development as well as public review of the draft environmental assessment and land protection plan. 

SCOPING

At the beginning of the planning process, the 

planning for the SLVCA was conducted in tandem 

with that for the San Luis Valley National Wildlife 

Refuge Complex CCP, at the time in the context of a 

broader, valley-wide conservation area. Public scoping 

meetings were held on March 29, 2011, in Alamosa, 

Colorado; March 30, 2011, in Monte Vista, Colorado; 
62 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

and March 31, 2011, in Moffat, Colorado. The scoping 

meetings were attended by approximately 50 people, 

many of whom provided input for the scoping process. 

Additionally, 14 written comments were received from 

organizations and members of the public. A press event 

and public meeting was held at Adams State College 

in Alamosa, Colorado, on January 4, 2012, at which the 

Secretary of the Interior, Ken Salazar, organized the 

presentation of several complementary initiatives for 

the San Luis Valley and Sangre de Cristo Mountains. 

One of these initiatives was landscape-scale conservation, which the Director of the Service presented as 

being embodied by the then SLVCA. Questions were 

answered and comments taken at a breakout session 

following the main meeting. The meeting was attended 

by more than 300 members of the public.

Together, these meetings and subsequent feedback 

helped the Service to see the questions and concerns 

of the public, as well as to refine the project boundary.

PUBLIC REVIEW OF THE DRAFT ENVIRONMENTAL 

ASSESSMENT AND LAND PROTECTION PLAN

The Service released the draft EA and LPP on 

May 9, 2012, for a 30-day public review period. The 

draft documents were made available to Federal 

elected officials and agencies, State elected officials and 

agencies, 17 Native American tribes with aboriginal 

interests, and other members of the public who asked 

to be added to our mailing list.

In February and May of 2012, refuge staff met with 

members of the land protection community in the San 

Luis Valley to discuss conservation priorities in the 

region. At these meetings, the Service discussed the 

SLVCA with representatives from entities including Rio Grande Headwaters Trust, Colorado Open 

Lands, Orient Land Trust, The Nature Conservancy, 

Colorado Cattlemen’s Agricultural Land Trust, the 

Natural Resources Conservation Service, Trust for 

Public Lands, and Colorado Parks and Wildlife. Positive, constructive feedback received at those meetings 

guided the Service in the development of the draft and 

final LPP and EA. 

In addition, three public meetings were held in 

Alamosa, San Luis, and Moffat, Colorado on May 14, 

15, and 16, 2012, respectively. Approximately 50 residents and representatives of elected officials attended 

the 3 meetings. 

Distribution and Availability

Copies of the land protection plan and environmental assessment were made available to Federal and 

State legislative delegations, tribes, agencies, landowners, private groups, and other interested individuals. 

Additional copies of the document are available 

from the following offices and contacts:

U.S. Fish and Wildlife Service

Region 6, Division of Refuge Planning

P.O. Box 25486–DFC

Denver, CO 80225

303 / 236 8132

http://www.fws.gov/mountain-prairie/

refuges/slv.php

U.S. Fish and Wildlife Service

San Luis Valley National Wildlife Refuge 

 Complex

8249 Emperius Road

Alamosa, CO 81101

719 / 589 4021
Glossary

acequia—A community-owned water distribution 

system found in Spain or former Spanish colonies; 

in the United States, found primarily in northern 

New Mexico and southern Colorado.

adaptive strategy—The ability of an ecosystem to 

keep ecological function while adjusting to longterm changes in the environment, or shifting to a 

new normal (such as climate change, established 

invasive species).

anthropogenic—Caused by human activity.

BLM—Bureau of Land Management, an agency of the 

U.S. Department of the Interior.

candidate species—A species of plant or animal for 

which the U.S. Fish and Wildlife Service has sufficient information on its biological status and 

threats to propose it for listing as endangered or 

threatened under the Endangered Species Act, 

but for which development of a proposed listing 

regulation is precluded by other higher priority 

listing activities.

CCP—See comprehensive conservation plan.

CFR—See Code of Federal Regulations.

Code of Federal Regulations (CFR)—Codification of 

the general and permanent rules published in the 

Federal Register by the executive departments and 

agencies of the Federal Government. Each volume 

of the CFR is updated once each calendar year.

comprehensive conservation plan (CCP)—A 15-year plan 

providing overall management guidance to a unit 

or complex of the National Wildlife Refuge System.

conservation easement—A legally enforceable 

encumbrance or transfer of property rights to a 

government agency or land trust for the purposes 

of conservation. Rights transferred could include 

discretion to subdivide or develop land, to change 

current land use practices, to sever water rights, 

or others as proper, and are specified by contract 

between the landowner and the conservation entity.

DOE—Department of Energy.

EA—See environmental assessment.

ecological resilience—The ability of an ecosystem to 

rebound from short-term changes to a landscape 

(such as wildfires, floods, pest outbreaks).

EIS—Environmental impact statement. 

endangered species—A species of plant or animal 

that is in danger of extinction throughout all or a 

substantial part of its range.

Endangered Species Act—A United States law passed 

by the U.S. Congress in 1973 with the purpose of 

protecting and recovering imperiled species and 

the ecosystems on which they depend.

environmental assessment (EA)—A National Environmental Policy Act (NEPA) compliance document 

that analyzes whether to prepare an environmental 

impact statement or a finding of no significant 

impact, facilitates compliance when no environmental 

impact statement (EIS) is necessary, or facilitates 

preparation of an EIS when one is necessary.

focal species—Species that represent a group of 

species vulnerable to similar threats.

HUC—Hydrologic unit code, a hierarchical system 

created by the U.S. Geological Survey to find 

locations and regions by hydrology.

LPP—See land protection plan.

land protection plan (LPP)—A document required by 

policy of the U.S. Fish and Wildlife Service before 

the establishment of new units of the National 

Wildlife Refuge System, or major expansions of 

existing units.

landscape conservation cooperative (LCC)—A publicprivate partnership intended to facilitate crosspolitical boundary conservation in the face of a 

changing environment through application of science.

Marxan—A software package used as a decision support tool for spatial conservation prioritization.

NEPA—National Environmental Policy Act.

NPS—National Park Service, an agency of the U.S. 

Department of the Interior.

NRCS—Natural Resources Conservation Service, 

an agency of the U.S. Department of Agriculture.

Region 6—An administrative unit of the U.S. Fish and 

Wildlife Service known as the Mountain–Prairie 

Region, which covers eight States: Colorado, 

Kansas, Montana, Nebraska, North Dakota, South 

Dakota, Utah, and Wyoming.

SCCA—Sangre de Cristo Conservation Area.

Service—U.S. Fish and Wildlife Service, an agency 

of the U.S. Department of the Interior.

SLVCA—San Luis Valley Conservation Area.

strategic habitat conservation—An iterative adaptive 

management framework designed to make sure 

that decisionmaking and management within the 

Service is science-based. Consists of four stages: 

biological planning, conservation design, delivery of 

conservation action, and monitoring and research. 
64 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

threatened species—A species of plant or animal that 

is likely to become endangered in the future.

trust species—Species for which the Federal Government has statutory responsibility, including 

threatened and endangered species, migratory 

birds, marine mammals, and interjurisdictional fish.

U.S.C.—United States Code.

USFS—U.S. Department of Agriculture Forest Service. 

USFWS—See Service.

USGS—United States Geological Survey, an agency 

of the U.S. Department of the Interior.
 Appendix A

Environmental Assessment 

This EA documents the purpose of and the issues, 

alternatives, and analysis for the SLVCA. The Service 

has already established the SCCA within the SLVCA 

boundary, as proposed in the draft EA. The SLVCA 

would be located largely in southern Colorado, but a 

small portion would be in northern New Mexico (figure 

EA–1). Section 1 provides background information and 

describes the conditions that led the Service to propose 

creation of the SLVCA for the protection of important 

wetland and upland habitats, primarily through conservation easements with willing landowners.

Introduction

The SLVCA is a landscape-level strategic habitat 

conservation initiative within the Southern Rockies 

Landscape Conservation Cooperative. The SLVCA 

would encompass the headwaters of the Rio Grande 

including its namesake San Luis Valley. The San Luis 

Valley is a large intermountain valley bounded by 

the San Juan and Sangre de Cristo mountain ranges, 

whose rain shadows create high desert conditions in the 

region. However, the complex hydrology of the valley, 

as well as the snowmelt runoff from the mountains, 

have created a variety of dynamic wetlands and riparian corridors on the mountain slopes and valley floor. 

These wetland areas support a diverse assemblage of 

plants and wildlife, including habitat for many trust 

species such as the southwestern willow flycatcher, 

western snowy plover, many species of migrating 

and nesting waterfowl, and 95 percent of the Rocky 

Mountain population of greater sandhill crane. The 

mountains themselves are also ecologically important, 

providing habitat for imperiled species such as Canada 

lynx and Mexican spotted owl, as well as serving as 

migration corridors for wildlife in this southernmost 

extension of the Rocky Mountains.

Anthropogenic practices including agriculture, 

changes in fire regime, and climate change have changed 

the historical vegetation of the San Luis Valley. Low 

human population density associated with the largely 

agricultural economy of the valley have resulted in the 

San Luis Valley and surrounding mountains keeping 

substantial parts of their biological value, particularly for migratory birds. However, rising agricultural costs, including those resulting from the recent 

State of Colorado requirement to augment surface 

flows to offset the impacts of ground water use, have 

led to an unsettled agricultural economy. The risk of 

second-home development could substantially reduce 

the quality of that habitat for sagebrush-dependent 

species. Surface and ground water diversions have 

significantly changed the amounts and timing of flows 

in most valley streams. In addition, ground water 

use has exceeded recharge rates in large portions of 

the valley. These factors, plus the impact of chronic 

drought, have resulted in a net loss of wetland habitat. 

The potential for farmers and ranchers to sell water 

rights from their lands or to convert current land use 

practices from agricultural to residential, industrial, or 

municipal uses would continue to grow and threaten 

the biological integrity of the San Luis Valley.

Proposed Action

The Service is moving to create the approximately 

4-million-acre SLVCA to conserve vital wildlife habitats and migration corridors through voluntary conservation easements. The SLVCA acquisitions would 

focus on the protection of riparian corridors, wetlands, 

sagebrush, and montane forests in the valley through 

the purchase of up to 250,000 acres of conservation 

easements. The lands protected via easement would 

remain in private ownership. These lands could continue to be grazed, hayed, farmed, or otherwise managed in accordance with current practices. However, 

subdivision and development would be restricted, 

subject to stipulations agreed-upon by the landowner 

and the Service. Furthermore, some easements may 

include stipulations that the exercise of water rights 

associated with these lands could be changed only if 

the proposed changes would be beneficial to wildlife.

Up to an additional 30,000 acres of fee-title acquisition from willing sellers has been proposed as part of the 

preliminary project proposal for this project. However, 

the present intent is to use fee-title acquisition only in 

SECTION 1—PURPOSE OF AND NEED FOR ACTION
66 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Figure EA–1. Map of the San Luis Valley Conservation Area, which would be part of a broader network of public 

and private conservation lands.
Appendix A—Environmental Assessment 67

limited circumstances to simplify the management of 

existing units of the National Wildlife Refuge System 

and when conservation objectives of those existing 

refuges clearly cannot be met using easements alone.

Unlike some other conservation areas of the 

National Wildlife Refuge System, in which objectives 

and the setting of priorities are largely based on modeling for one species or a guild of species, the SLVCA 

is intended to meet all the objectives of a complex 

geographic, ecological, and political environment. It 

therefore has a diverse range of goals:

■ conserve, restore, enhance, and protect wetland 

and riparian habitat, an important breeding and 

foraging resource in the high mountain desert for 

migratory shorebirds, waterfowl, and neotropical 

passerine birds

■ support the recovery and protection of threatened 

and endangered species that occur in the SLVCA, 

and reduce the likelihood of future listings under 

the Endangered Species Act by prioritizing key 

habitat for listed species and species that are candidates for listing 

■ protect the integrity of these habitats by preventing 

fragmentation and conversion of native vegetation

■ conserve working landscapes based on ranching 

and farming activities that support a viable agricultural industry 

■ promote ecological resiliency and adaptive capacity by connecting together the existing network of 

public and private conservation lands

Decisions to Be Made

Based on the analysis provided in this final EA, 

the Regional Director of the Service will make two 

decisions:

1. Figure out if the Service should establish the 

SLVCA, in accordance with its land protection 

planning policy.

2. If yes, figure out if the selected alternative would 

have a significant impact on the quality of the human environment. This decision is required by the 

NEPA. If the quality of the human environment 

would not be affected, a “finding of no significant 

impact” will be signed and will be made available 

to the public. If the preferred alternative would 

have a significant impact, an environmental impact statement will be prepared to further address 

those impacts.

Issues Identified and 

Selected for Analysis

A description of issues identified and selected for 

analysis is in chapter 1. 

Related Actions and 

Activities

A description of related actions and activities is 

in chapter 1.
68 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

This section describes the two alternatives identified for this project: 

■ no-action alternative

■ proposed action, giving the Service the authority 

to create the SLVCA

These alternatives were developed according to 

NEPA §102(2)(E) requirements to “study, develop, and 

describe proper alternatives to recommend courses of 

action in any proposal that involves unresolved conflicts 

concerning alternatives uses of available resources.” 

The alternatives consider the effects of a conservation 

easement program with limited fee-title acquisition 

within the project area boundary identified in this EA.

In addition, alternatives that were dropped from 

detailed study are briefly discussed.

Alternative A (No Action)

Under the no-action alternative, the areas outside 

of existing protected areas would largely remain in 

private ownership and subject to changes in land 

use or habitat type. Some added protection is likely 

because of ongoing conservation easement initiatives 

in the San Luis Valley by public entities such as the 

NRCS and nongovernmental organizations such as 

the Colorado Cattleman’s Agricultural Land Trust 

and Colorado Open Lands. 

Alternative B (Preferred 

Alternative)

Under the preferred alternative, the Service would 

establish the SLVCA in southern Colorado and northern New Mexico. The project boundary encompasses 

approximately 4 million acres. Within this boundary, 

the Service would strategically acquire from willing sellers perpetual conservation easements on up 

to 250,000 acres through purchase or donation. The 

Service would also consider fee-title acquisition on 

up to 30,000 acres. 

Conservation easements are both a cost-effective 

and politically effective means of land protection. They 

stem from the “bundle of rights” concept of land ownership (Merenlender et al. 2004), wherein, like severed 

surface and mineral rights for a given parcel, a part of 

the land title is severed and transferred to a land trust 

or public agency for conservation purposes. They are 

quite popular for a variety of reasons. Because they 

allow the property owner to continue using the land, 

subject to agreed-upon stipulations, they protect working landscapes, which is a priority of the America’s 

Great Outdoors initiative. Perpetual conservation 

easements provide a one-time source of income to the 

seller or a tax incentive to the donor, and can even be 

an estate planning tool (Engel 2007). In many cases, 

they can meet the conservation objectives of the 

Service without our incurring the costs associated 

with managing fee-title land; furthermore, the land 

remains on the county tax rolls. In the SLVCA, the 

Service seeks to protect up to 250,000 acres through 

conservation easements and 30,000 acres in fee title. 

Potential easements or fee-title lands would be 

prioritized based on wildlife needs in the project area, 

which include wetland, riparian, montane forest, and 

upland habitats. The Service may also investigate the 

possibility of acquiring properties with water rights 

whose protection may benefit habitat elsewhere in the 

valley. Chapter 4 describes these priorities in detail.

Alternatives Considered 

but Dropped from Further 

Analysis

The reasons for dropping three alternatives from 

further analysis are described by each nonconsidered 

alternative below.

Voluntary Landowner 

Zoning or County Zoning

Under this alternative, landowners would voluntarily petition their county commissioners to create 

a zoning district to direct the types of development 

that can occur in an area. An example of citizen-initiated zoning is when landowners would petition the 

county government to zone an area as agricultural, 

precluding certain types of nonagricultural development, such as residential subdivision or construction 

of a solar energy facility. However, zoning decisions 

are easily changed and thus do not ensure perpetual 

habitat protection. Also, agricultural zoning would be 

inadequate because water has become an increasingly 

expensive and limiting resource and it thus would not 

in itself stop continued conversion from flood-irrigated 

vegetation to less biologically diverse cultivated crops. 

SECTION 2—ALTERNATIVES
Appendix A—Environmental Assessment 69

This conversion has often been accompanied by the 

replacement of flood irrigation practices with centerpivot irrigation. Although center-pivot irrigation offers onsite water efficiency, it results in land cover that 

is far less suitable to wildlife than native vegetation 

or even flood-irrigated agriculture. Because of these 

reasons, this alternative was not investigated further. Management by others

Some governmental and nongovernmental organi-

zations are active in promoting conservation within 

the SLVCA and the broader San Luis Valley region. 

Current land managers include the Colorado Parks 

and Wildlife, Colorado State Land Board, BLM, Na-

tional Park Service, USFS, and the Service. Additional 

land is conserved in fee title by The Nature Conser-

vancy, and conservation easements are held by Ducks 

Unlimited, Rio Grande Headwaters Trust, the NRCS, 

and the Colorado Parks and Wildlife, among others.

Although the mission and focus of these organiza-

tions may be different than the mission of the Refuge 

System, they have made tremendous strides in pro-

tecting wildlife habitat in the San Luis Valley. The 

Service hopes to add capacity to these existing efforts 

and provide the ability to focus on habitats important 

for Federal trust species through the SLVCA. Fee-Title Acquisition Only

Much of the publicly owned land mentioned in 

the previous section has been managed for conserva-

tion purposes for decades; indeed, Great Sand Dunes 

National Park and Preserve was originally established 

in 1932 as a National Monument. Fee-title ownership 

allows the strongest protection for the habitat and 

allows the greatest flexibility for adaptive manage-

ment in response to new data or changing conditions. 

However, acquisition of new public land on the scale of 

the SLVCA is politically untenable and, given the low 

appropriation of Land and Water Conservation Fund 

monies, it is also financially unrealistic. For these rea-

sons as well as the expense of managing more public 

lands, it is the Service’s policy to acquire the minimum 

interest necessary to reach conservation objectives.
70 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

SECTION 3—AFFECTED ENVIRONMENT

For alternatives A and B described earlier, the 

following narrative documents the analysis of environmental effects expected to occur from carrying 

out each of the alternatives.

Effects on the Physical 

Environment

The estimated effects of each alternative on mineral, soil, and water resources, and on the Service’s 

ability to address climate change, are described below.

Alternative A (No Action)

Development and associated habitat loss could 

continue on lands outside of existing protected areas; 

in riparian areas, development may cause erosion and 

sedimentation that ultimately could adversely affect 

aquatic species like the Rio Grande cutthroat trout. 

Further land protection would be limited to the efforts 

of other agencies and organizations. The Service’s role 

would be limited to programs such as Partners for 

Fish and Wildlife; no Land and Water Conservation 

Fund monies would be expended in the project area 

by the Service for further land protection outside of 

the immediate vicinity of existing refuge units. Important water-dependent wildlife habitat would remain 

vulnerable to reallocation of surface water offsite or 

changes to how existing water rights are exercised.

Alternative B (Preferred Alternative)

The implementation of the goals of the SLVCA 

would primarily support current land use practices, 

and is therefore unlikely to substantially affect soil resources in the valley. There may be some reduction in 

erosion and sedimentation because of the prevention 

of subdivision and development. The SLVCA would 

not supersede existing third party mineral rights, and 

the program is therefore unlikely to affect mineral 

resources. If the mineral estate has not been severed, 

the easement may include restrictions on surface occupancy, but the Service would not, and cannot, prevent 

a mineral owner from accessing their minerals. The 

Service is unlikely to pursue acquisition of interests 

in lands with outstanding surface mineral leases or 

rights because the associated destruction of surface 

vegetation and need for reclamation diminishes the 

wildlife value of such land. In some circumstances, 

habitat that depends on continuation of current water 

use practices would be protected from degradation 

caused by the sale of surface water rights or substantial changes to water use. 

Effects on the Biological 

Environment

This section describes the likely effects of the project on species and their habitats.

Alternative A (No Action)

The Service’s Partners for Fish and Wildlife Program would remain active within the project area, 

where it works cooperatively with landowners to 

voluntarily improve habitat on private land. Habitats 

would continue to be protected because of the ongoing 

efforts of agency partners and nongovernmental 

organizations, primarily through easements paid for 

by private donations, the NRCS Wetland Reserve 

Program, and North American Wetlands Conservation Act grants. These efforts are laudable and have 

conserved valuable habitat, particularly wetlands. 

However, they tend to underrepresent nonwetland 

riparian forest and uplands such as sagebrush steppe, 

both of which are particularly important for federally 

listed species and candidates for listing in the project area. Further, the demand for money under both 

the North American Wetlands Conservation Act and 

the Wetland Reserve Program is much higher than 

for historically available money. Also, unlike a Land 

and Water Conservation Fund easement program, 

the North American Wetlands Conservation Act 

requires matching funds, which are currently available through funding sources such as Great Outdoors 

Colorado and State tax incentives. Therefore, there 

would likely continue to be erosion of habitat quality 

and a decrease in ecological resiliency because of land 

SECTION 4—ENVIRONMENTAL CONSEQUENCES

Discussions of the resources and affected environment are in chapter 2.
Appendix A—Environmental Assessment 71

cover changes and associated fragmentation, introduction of exotic species, and construction of structures 

that are incompatible with habitat use by some wildlife.

Outright habitat loss because of conversion of land 

to other uses is a chronic, long-term threat to wildlife 

in many parts of the San Luis Valley. In the SLVCA, 

this can take the form of changes in irrigation schemes 

and residential and industrial development. This habitat destruction, along with construction of associated 

infrastructure such as water diversion structures, can 

result in the fragmentation of habitat. The effects of 

fragmentation on wildlife have been intensively studied in ecology and wildlife biology (for a conceptual 

review, see Collinge 2009). 

Both the loss and fragmentation of riparian habitat are real concerns in the SLVCA. Riparian areas 

are necessary for the maintenance of medium and 

large mammal diversity in agricultural landscapes 

(for example, Hilty and Merenlender 2004), and for 

both breeding and stopover habitat for neotropical 

migratory songbirds in human-altered landscapes 

(Pennington et al. 2008). Riparian areas provide nest 

habitat for the threatened southwestern willow flycatcher and the threatened yellow-billed cuckoo, and 

the slow but continued loss of this habitat under alternative A would have an impact not just on regional 

species diversity but also on the potential persistence 

of imperiled species. 

Besides providing habitat in and of themselves, 

riparian areas also serve as corridors for animal movement. Facilitating animal movement across complex 

mosaic landscapes is essential in a time of global 

environmental change. One of the greatest ecological 

threats of climate change is that species and varieties 

that are adapted to specific environmental conditions 

may die out because they are isolated from habitats 

that may have those conditions in the future (Loss et 

al. 2011). Under alternative A, there would be continued risk of development in previously contiguous 

riparian corridors.

Alternative B (Preferred Alternative)

Establishment of the SLVCA, combined with the 

existing SCCA, would enable the Service to permanently protect up to 530,000 acres of vital wildlife 

habitat in addition to that already held in Alamosa, 

Baca, and Monte Vista Refuges. While there are conservation initiatives by other government agencies and 

private land trusts underway in the project area, the 

SLVCA specifically targets habitat that is necessary for 

migration or breeding of Federal trust species, namely 

migratory birds and a handful of federally listed and 

candidate nonbird species. The conservation area 

should complement and enhance the ecological benefits 

of existing public and private conservation lands and 

habitat improvement programs by capturing habitats 

not included in these programs and by helping to link 

together the existing protected area. 

The use of easements to protect and buffer riparian habitats under alternative B would benefit both 

obligate riparian species like the southwestern willow 

flycatcher, bats like the Yuma myotis, and species that 

simply use the riparian areas as corridors to move from 

point to point, like bobcat and black bear. Of particular interest are the willow and cottonwood riparian 

forests along the tributaries of the Rio Grande, which 

are used by dozens of species of migratory songbirds. 

In the rivers and tributaries themselves, the use 

of easements could support conditions suitable for 

fish such as the Rio Grande cutthroat trout, Rio Grande 

chub, and Rio Grande sucker by preventing development of houses and roads, which can cause siltation 

and changes in water chemistry and temperature. 

Easements would also prevent conversion of shrub 

steppe near riparian areas to cropland, which can lead 

to increases in sediment, nitrogen loads, and temperatures in associated streams.

The presence of mesic (wet) habitats in the midst 

of a high-mountain desert provides an irreplaceable 

resource to regional, and in some cases continental, 

populations of breeding and migrating shorebirds, 

wading birds, and waterfowl. Water costs in the San 

Luis Valley are increasing because of restrictions on 

the use of ground water, and water is likely to become 

an increasingly complex issue because of projected 

changes in runoff timing and uncertainty about future 

precipitation trends (Ray et al. 2008). Many wetlands 

in the SLVCA that are important to migratory birds 

rely on current land use practices. We hope to work 

with willing landowners to maintain these practices 

to benefit important habitat. Consequently, on some 

properties with important water-dependent habitat, 

the easements may restrict the sale of water off the 

property and prevent conversion of mesic, native plant 

communities to domestic crops. 

Sagebrush shrubland and steppe are not widespread 

in the project area, but are found in a ring above the 

desert scrubland and below the pinyon-juniper woodland 

in the far northern, southeastern, and southwestern 

portions of the valley. The Poncha Pass area was historically home to a small lek of the federally threatened 

Gunnison sage-grouse. Sage-grouse, as well as other 

sagebrush obligates, are particularly sensitive to disturbance, especially the construction of vertical structures in their habitat, which could happen if homes and 

associated power lines were constructed. With the 

lack of attention being given to that habitat type by 

conservation partners at present, land protection under alternative B is likely to play an important role in 

preventing modification of this important ecosystem.
72 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Effects on Cultural 

Resources

The estimated effects of each alternative on cultural resources are described below.

Alternative A (No Action)

Some cultural resources could be adversely affected 

by activities such as development and road construction on lands outside of existing public and private 

conservation lands. While the rate of development is 

not rapid now, the San Luis Valley is rich with millennia of human history, and much of the valley’s history 

is poorly documented. There are legitimate concerns 

that important sites may be destroyed or irreparably 

disturbed in the absence of protection.

Alternative B (Preferred Alternative)

There is the potential for greater protection of 

cultural resources than under alternative A because 

the easement terms that prevent development of land 

in ways that could adversely affect wildlife could also 

prevent destruction of Native American, Hispano, and 

other historic American sites.

Effects on the 

Socioeconomic Environment

This section describes the estimated effects of the 

alternatives on land use, ecosystem services, land 

ownership, and the regional economy.

Alternative A (No Action)

Landownership patterns would continue to change 

in accordance with market forces, as will resulting 

modification of ecosystem services and changes in cost 

of public service delivery by local government. Landowner compensation through conservation easements 

would remain available through other Federal programs 

and the efforts of nongovernmental organizations. 

Alternative B (Preferred Alternative)

Following are the social and economic impacts of 

conservation easements and fee-title acquisitions.

Conservation easements provide public benefits 

for local residents, communities, and governments. 

Easements and fee-title acquisitions also reshape 

future development patterns, affect property values, 

and inject new money into local communities. There 

are many dynamic variables at play when considering the social and economic effects of conservation 

easements, especially given that potential purchases 

may span decades. Because of future uncertainty surrounding such factors as the likelihood and timing of 

easements; the availability of Service money to buy 

lands; and population growth, land values, and agricultural commodity prices, the social and economic 

impacts of the easements cannot be quantified in this 

analysis. However, these impacts can be described 

qualitatively. This analysis discusses the following 

effects of conservation easements in the SLVCA:

■ conservation values in the region 

■ benefits to local communities

■ landowner compensation

■ effects to local government net revenue

Table A, located at the end of this section, provides a summary of the social and economic impacts 

of conservation easements and fee-title acquisitions 

in the SLVCA.

Conservation Value

Conservation easements can protect values associated with biodiversity and wildlife abundance, keep 

aesthetic beauty, and protect social and culturally significant features of landscapes and livelihoods (Millennium Ecosystem Service Assessment 2005, Ehrlich and 

Ehrlich 1992, Daily 1997). Ecosystem services, such 

as water purification, oxygen production, pollination, 

and waste breakdown, are also supported for local 

residents through land preservation (Millennium Ecosystem Service Assessment 2005). The primary public 

benefit of Service conservation easements is enhanced 

and preserved wildlife habitat. As development stressors increase over time, many key off-refuge habitat 

areas may become less available because of conversion 

to nonwildlife habitat uses. Habitat preservation has 

been shown to stabilize and increase wildlife populations (Reynolds et al. 2001). Conservation easements 

on private lands strengthen the resiliency of species 

habitat and provide opportunities for wildlife movement and adaptation for years to come. 

Benefits to Local Communities

Although local residents may not be able to 

explicitly use or access land protected by conservation easements, protected lands act as a buffer that 

benefits residents through increased biodiversity, recreational quality, and hunting opportunities on publicly accessible wildlife refuges and on some private 

lands (Rissman et al. 2007). It is well documented that 

open space carries positive values to local residents 

and communities, as well as to passersby (McConnell 

and Walls 2005). This is evidenced by the success of 

open space preservation ballot initiatives at the local, 

county, and State levels. Banzhaf et al. (2006) point 

out that between 1997 and 2004, more than 75 percent 

of the more than 1,100 referenda on open space conservation that appeared on ballots across the United 

States passed, most by a wide margin. 
Appendix A—Environmental Assessment 73

It is also well documented that open space and 

protected natural areas can increase surrounding 

property values (see McConnell and Walls 2005 for 

a comprehensive review). The reciprocating value of 

open space on property values varies depending on 

landscape characteristics and location attributes (for 

example, distance to the conserved area) (Kroger 2008). 

The permanence of the open space is also an influencing factor. Typically, open space that is permanently 

protected (such as refuge lands and lands protected 

with perpetual conservation easements) generates 

a higher enhancement value to local properties than 

land that has the potential for future development 

(Geoghegan et al. 2003). Location and demographic 

factors in the region can also influence the relative 

level of property enhancement value. For instance, 

open space may generate larger amenity premiums for 

property in more urbanized areas and where median 

incomes are higher (Netusil et al. 2000), which is not 

to say there is not the chance for property values to 

increase substantially in rural areas as well (Crompton 

2001, Phillips 2000, Thorsnes 2002, Vrooman 1978). 

Conservation easements would also inject new 

money into the local economy. The sale of conservation 

easements provides landowners with more revenue. 

Some percentage of this money may be spent in the 

local economy, including purchasing new real estate, 

consumer goods, or services in the local area. Conservation easements may also help keep the character 

of a region by protecting a traditional and historical way of life and the associated working landscape. 

Land with historical commercial use, such as ranching, forestry, and farming, is often compatible with or 

beneficial to wildlife refuge objectives (Jordan et al. 

2007, Rissman et al. 2007). Conservation easements 

provide financial benefits for landowners that may 

enable them to preserve the natural and historical 

value of their farm, ranch, and open space lands, and 

to pass this legacy on to their children and grandchildren. In addition to supporting a cultural heritage, the 

preservation of farming and ranching operations can 

result in economic benefits to the local economy. Farmers’ costs for equipment, supplies, and materials may 

be spent in the local economy, thus stimulating local 

businesses and supporting local employment. Farm 

workers would also spend their salaries in the local 

economy, thus supporting further local employment. 

Conservation easements may also result in increased 

recreation-related spending by visitors. 

Landowner Compensation

The Service would buy conservation easements from 

willing sellers at fair-market value. The fair-market 

value of a conservation easement is found through an 

appraisal process. An appraiser estimates how much 

the land would sell for unencumbered by the conservation easement (the “before” value) and how much the 

land would sell for with the conservation easement in 

place (the “after” value). The value of the conservation 

easement is equal to the before value minus the after 

value, or the difference in the fair-market value of the 

property with and without the easement. Landowners 

may also choose to donate conservation easements to 

the Service. The donation of a conservation easement 

may qualify as a tax-deductible charitable donation, 

which may result in Federal income tax benefits. The 

sale of a conservation easement for less than its fairmarket value (called a “bargain sale”) may also qualify 

for tax deductions. Landowners may be able to claim 

a charitable income tax donation equal to the difference between the fair-market value and the bargain 

sale price of their easement. Income from the sale of 

a conservation easement may be taxable. Please note 

that the Service does not give tax advice. Landowners considering entering into a conservation agreement with the Service should consult a tax advisor or 

attorney for advice on how a conservation easement 

would affect their taxes and estate. Additionally, the 

Service pays for appraisals and closing costs for easements negotiated under the SLVCA.

Conservation easements reduce the value of the 

encumbered property. A conservation easement would 

reduce the fair-market value of an estate because the 

easement permanently removes some of the estate’s 

development potential. The reduction in value depends 

on the potential development value of the land and the 

level of restriction agreed-upon in the easement. In 

general, an easement on land located in an area with 

high-development pressure would have a greater 

effect on the value of the land than an easement on 

land located in an area with low development pressure, and an easement that was more restrictive would 

have a greater effect on the value of the land than an 

easement that is less restrictive. The Service would 

buy easements at their appraised fair-market value; 

therefore, easements on lands with high-development 

pressure would receive higher payments. 

Effects on Local Government Net Revenue

The effects of conservation easements on the net 

revenue of local government are complex and speculative; many variables are at play, and realizing the 

effects often requires time. Local governments collect 

revenue through intergovernmental transfers, property taxes, sales taxes, personal income taxes, and 

other charges, such as permitting. These revenues are 

then spent to provide community services such as fire 

and police services, schools, infrastructure, and public 

spaces. Conservation easements affect the location of 

future development, and therefore affect both future 

revenues and costs for local governments. The following sections describe the possible effects to local 

government revenues and costs. Overall, the SLVCA 

conservation easement program is expected to have 
74 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

negligible effects on local government net revenues 

(revenues minus costs). 

Effects on Local Government Revenues. Property 

taxes constitute the largest source of local governments’ own revenue (Urban Institute and Brookings Institution 2008), and are not expected to be 

substantially affected by conservation easements in 

the SLVCA. Property taxes are assessed based on 

the value of property. For most types of properties, 

county assessors use fair-market value to find property tax liabilities; however, agricultural land is often 

assessed differently. In many States, the assessed 

value of agricultural land is based on the productive 

value of the land rather than on the fair-market value 

of the property. The fair-market value of land is the 

amount that a property is estimated to sell for. This 

value includes both the productive value of the land 

and any speculative value associated with the possibility of developing the land. Conservation easements 

reduce the fair-market value of property by removing 

the speculative value associated with possible development; however, conservation easements generally 

do not affect the productive value of agricultural land. 

The SLVCA would include land in two States: Colorado and New Mexico. In both States, property taxes 

for agricultural land are assessed based on the productive value of the land or farm income1

 (Colorado Division of Property Taxation 2006; New Mexico Taxation 

and Revenue Department 2011). In the SLVCA, most 

properties that would enter into conservation easement agreements with the Service would be classified 

as agricultural land; thus, there would be little effect 

on the current property tax base for the nine-county 

area. Some of the lands in the SLVCA that would 

enter into easements are now fallow and do not classify 

as agricultural lands. For these properties, assessors 

may assess the fair-market value of the land based 

only on the uses allowed by the easement. This could 

result in a small reduction in property tax revenue 

in some counties within the region. The reduction in 

property taxes would be dependent on the percent of 

easement acres that are bought on fallow land (versus 

agricultural land), and on the reduction in the market 

value of the fallow lands. 

The donation or purchase of any fee-title lands 

would reduce the amount of property tax revenue 

collected by local governments because the Service is 

exempt from taxation on its property holdings. Under 

Federal fee-title ownership, counties would qualify for 

reimbursement of some property tax revenue foregone 

under the Refuge Revenue Sharing Act of 1935, which 

allows the Service to make annual payments to local 

governments in areas where fee-title purchases have 

removed land from the tax rolls. Under provisions of 

1

Special rules and statutes apply in each State to figure out if land 

in agricultural production and land in conservation easements is 

eligible to be assessed as agricultural land

the Refuge Revenue Sharing Act, local counties receive 

an annual payment for lands that have been bought 

by full fee-title acquisition by the Service. Payments 

are based on the greater of 75 cents per acre or 0.75 

percent of the fair-market value. The exact amount 

of the annual payment depends on congressional 

appropriations, which in recent years have tended 

to be substantially less than the amount required to 

fulfill the authorized level of payments. In fiscal year 

2010, actual Refuge Revenue Sharing payments were 

22 percent of authorized levels.

Local government revenue associated with personal income is expected to remain relatively constant 

within the nine-county area. Conservation easements 

and fee-title acquisitions in the SLVCA would affect 

the location and distribution of development, but are 

not expected to change the rate or density of human 

population growth. Redistribution of population growth 

could affect the distribution of personal income–related 

revenues across the counties, but is expected to have 

little effect on total revenues within the nine-county 

area. There would be a one-time increase in landowner 

income as the Service buys the easements. 

Effects on Local Government Costs. Land protection through conservation easements could result in a 

reduction in future expenditures for local governments 

and municipalities. New residential developments 

require local governments to provide services such as 

fire protection, police services, and schools, and to construct new infrastructure such as roads, parks, and water 

and electric-delivery systems. The costs to provide 

government services for new residential developments 

often exceed new revenues derived from the developments. This is especially true for rural residences, which 

tend to have higher costs for county governments and 

school districts than urban residences. In 2001, the 

American Farmland Trust found that, on average, the 

cost to provide community services to new residential 

developments was $1.15 for every $1.00 of revenue 

generated by those developments (American Farmland 

Trust 2001; Coupal et al. 2002). A study conducted in 

Wyoming found that community service costs averaged 

$2.01 for every $1.00 of revenue for rural residential 

lands; in contrast, the average cost to provide services 

for lands under agricultural production averaged $0.54 

for every $1.00 of revenue (Taylor and Coupal 2000). 

Impacts on Federal Permitting and Property Rights of 

Nonparticipants

Neither the authorization nor the establishment of 

the SLVCA would affect the administration of lands by 

other Federal agencies; the SLVCA boundary is simply an acquisition boundary within which the Service 

could acquire easements or property. Landowners 

who choose to take part in the program would sell or 

donate certain property rights to the Service. There 

would be no impact on adjacent property owners.
Appendix A—Environmental Assessment 75

Unavoidable Adverse 

Impacts

This section describes adverse effects which may be 

unavoidable when carrying out alternatives A and B.

Alternative A (No Action)

Loss of wetland, riparian, and upland vegetation 

and their associated habitat values would continue 

because of development of areas outside of those protected by partner agencies and land trusts.

Alternative B (Preferred Alternative)

No direct or indirect unavoidable adverse impacts 

to the environment would result from choosing alternative B. An easement program would not result in 

adverse impacts on the physical or biological environment. Choosing an approved boundary for the SLVCA 

and concurrent authorization to go forward with an 

easement program would not, by itself, affect land 

ownership or value, or other aspects of the socioeconomic environment.

Irreversible and 

Irretrievable Commitment of 

Resources

Any commitments of resources that may be 

irreversible or irretrievable because of carrying out 

alternatives A or B are described below.

Alternative A (No Action)

There would be no commitment of resources by the 

Service if alternative A were selected. The Service 

could still exercise its authority to acquire inholdings 

or for minor expansions of existing refuges, but would 

not be obligated to do so.

Alternative B (Preferred Alternative)

The establishment of the SLVCA would not, of 

itself, constitute an irreversible or irretrievable commitment of resources. However, if interests in land 

were acquired through the use of Land and Water 

Conservation Fund or donations, the administration 

of the easement provisions or donated property would 

require an irreversible and irretrievable commitment 

of resources. The amount of annual monitoring activity and associated compliance actions will be directly 

related to the number and size of easements acquired 

over time. We anticipate these efforts will represent 

a minor increase in Service costs in the near future. 

However, these costs could grow to very significant 

levels if and when the conservation area grows and 

the Service holds easements on acreages approaching 

the limits set by the Director under this plan.

Short-Term versus LongTerm Productivity

Following is a discussion of short- and long-term 

effects of the alternatives.

Alternative A (No Action)

Continued efforts to conserve habitats would be 

ongoing through the efforts of Service activities like 

Partners for Fish and Wildlife and the efforts of other 

agency and nonprofit partners. Important wetland and 

upland habitats would be expected to continue to be 

lost at current rates of conversion, which would have 

long-term negative implications on the maintenance 

of the ecological communities they support.

Alternative B (Preferred Alternative)

The Service would be authorized to buy perpetual 

easements only from willing sellers, providing an immediate short-term economic benefit to landowners. 

This may provide capital for expansion of agricultural 

operations, or simply allow struggling operators to 

stay in business. This is particularly relevant given the 

changes to Colorado water law, which now requires 

ground water users to buy increasingly expensive surface water to decrease their impact on senior surface 

water users. This infusion of capital at an opportune 

time would likely have important long-term benefits 

to the economy of the San Luis Valley. The conservation of habitats under this program would also have 

important short- and long-term ecological benefits. The 

program would preserve habitat now used by wildlife, 

including federally protected species. This would result 

in the preservation of the area’s biodiversity, which 

is important for long-term ecosystem stability and 

function in arid environments (Maestre et al. 2012). 

By preventing fragmentation, particularly in wildlife 

corridors like riparian areas and along the Sangre de 

Cristo Mountains, the program would promote longterm ecological resiliency to habitat perturbations 

such as large wildfires and climate change.

Cumulative Impacts

As defined by NEPA regulations, a cumulative 

impact on the environment “results from the incremental impact of the action when added to other past, 

present, and reasonably foreseeable future actions 

regardless of what agency or person undertakes such 

other actions” (40 Code of Federal Regulations [CFR] 
76 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

1508.7). The following describes the past, present, and 

reasonably foreseeable actions related to the SLVCA. 

A discussion follows about the cumulative impacts of 

these actions in combination with the actions of alternatives A and B.

Past, Present, and Reasonably

Foreseeable Future Actions

Some private and public organizations have successfully conducted land protection programs in the 

San Luis Valley through negotiation of conservation easements with willing landowners. One specific 

example is a coalition of local governments, landowners, and nonprofit organizations that is working to 

conserve land as part of their mitigation strategy in 

the San Luis Valley Habitat Conservation Plan that 

was released in November 2012. The Service assumes 

this would likely continue in the future. 

The State of Colorado is carrying out new laws 

about ground water augmentation, where landowners 

who use ground water may have to buy surface water 

rights to offset any adverse impacts on downstream 

users. In response to these upcoming regulations, the 

community, largely through the leadership and support 

of the Rio Grande Water Conservation District and 

county governments, is developing locally managed 

subdistricts of the Rio Grande Water Conservation 

District. The subdistricts are meant to be locally designed and managed programs that will provide well 

users alternatives to individual augmentation plans.

There is ongoing interest in the San Luis Valley for 

renewable energy development. There are small-scale 

commercial solar facilities now deployed in the San Luis 

Valley, and the Department of Energy and the BLM are 

studying the impacts of more facilities being developed 

on public land (BLM and DOE 2010). The BLM is now 

reviewing the potential impacts of expanded geothermal 

leasing on public lands in the San Luis Valley (BLM 2012). 

Alternative A (No Action)

Under this alternative, there would be no cumulative impacts on the environment because the Service 

would not undertake any more land protection measures.

Alternative B (Proposed Action)

The continuing land protection efforts of others, 

combined with the proposed action, may have nonlinear, positive effects on wildlife populations. Because 

this alternative focuses on federally regulated species 

(such as priority migratory bird species and species 

listed or being considered for listing under the Endangered Species Act), implementation would result 

in accelerated protection of habitats for those species. 

Service seeks to coordinate its land protection efforts 

by promoting active communication with our conservation partners on land protection opportunities as 

they arise so that the organization whose program is 

most proper can seek the acquisition of a particular 

land interest. The public and private conservation 

entities in the San Luis Valley have a longstanding 

friendly relationship and view each other’s conservation objectives as largely complementary. However, 

there are specific instances where potential conflict 

could arise without this communication, such as riparian habitat of the southwestern willow flycatcher. The 

Service does not intend to compromise the ability of 

local government to meet their mitigation targets in 

the San Luis Valley Habitat Conservation Plan. To 

this end, the Service would not undertake any acquisition of southwestern willow flycatcher habitats along 

the Rio Grande or its tributaries without discussing 

the opportunity with our conservation partners. The 

Service would defer to partners in all instances where 

they need to seek an interest in the land first.

The impacts of new Colorado water law on water 

availability and cost may be cumulative with the 

impacts of the Service’s easements, which, depending on the habitat present on a specific property, may 

include language restricting the sale of surface water rights from lands protected under this program. 

Because the easements would keep current water use 

practices on lands where an interest is acquired, these 

impacts are unlikely to be significant.

The presence of a Service interest in land could 

preclude construction of commercial energy production or transmission infrastructure on that property 

if such activity is deemed to be incompatible with the 

purpose of the SLVCA. This would result in unknown 

effects because of potentially limiting where such 

facilities could be sited, but the impacts of such limitations on economics and the attainment State and Federal renewable energy requirements are speculative 

at best, and are outside of the scope of this analysis.

Any impacts of the proposed action that are 

cumulative with the actions of others would largely 

be decided by (1) the number of landowners willing 

to enter into easement agreements with the Service 

and (2) the amount of money available for acquisition 

of these easements. 
Appendix A—Environmental Assessment 77

Table A. Social and economic impacts of conservation easements and fee-title acquisitions.

Issue

Social and economic impacts

Conservation easements Fee-title acquisitions

Conservation 

value

■ Migration corridors and habitat for deer, elk, 

moose, and migratory birds would be preserved.

■ Same as for easements plus the conservation 

value of fee-title lands may be greater than easement lands because the Service has the ability 

to increase conservation value through projects 

on the land.

Affects to local 

communities

■ The public would enjoy increased biodiversity, 

recreational quality, and hunting opportunities 

on nearby publicly accessible refuges and some 

private lands.

■ Neighboring property values may increase.

■ Positive economic impacts may result from new 

landowner money injected into the local economy.

■ Traditional and historical ranching and farming 

landscapes would be preserved.

■ Same as for easements except traditional and 

historical ranching and farming landscapes may 

not be preserved.

■ Positive economic impacts may also result from 

increased Service habitat improvement expenditures injected into the local economy.

■ Possible increase in refuge visitation and associated impacts of visitor spending in the local economy. However, neighbors and other public may 

be affected by increased accesses to refuge lands.

Landowner 

compensation

■ Landowners would be compensated for the fairmarket value of the easement.

■ Easements would reduce the fair-market value 

of the encumbered property.

■ Landowners keep most use rights, but forfeit 

their right to develop or subdivide the land. Other 

possible restrictions include development of vertical structures, diversion or sale of water rights.

■ Landowners would be compensated for the fairmarket value of the land.

■ Landowners would forfeit all rights of ownership and turn the property over to the Service.

Affects on local 

government net 

revenue

■ No changes to property tax revenues are expected 

for agricultural lands.

■ Property tax revenues from fallow lands would 

decrease.

■ Other government revenues, such as personal 

income tax, may be redistributed throughout 

the region.

■ Land protection through conservation easements 

could result in reduced future service costs for 

local governments and municipalities.

■ The Service does not pay property taxes on land 

they own; thus, county tax revenue would decline.

■ Lost property tax revenues would be partially 

replaced with Refuge Revenue Sharing payments. 
78 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

SECTION 5—COORDINATION AND ENVIRONMENTAL REVIEW

This section describes how the Service coordinated 

with others and conducted environmental reviews of 

various aspects of the project proposal and analysis. 

Additional coordination and review will be needed to 

carry out the preferred alternative.

Agency Coordination

The Service has discussed the establishment of 

the SLVCA with other Federal (USFS, National 

Park Service, BLM, and NRCS), State of Colorado 

(Colorado Parks and Wildlife, Colorado Water Conservation Board), local county governments, and 

regional entities (Rio Grande Water Conservation 

District) through a series of meetings and correspondence. Tribes with an aboriginal interest in the San 

Luis Valley and surrounding mountains (Pueblo of 

Picuris, Cochiti Pueblo, Jemez Pueblo, Jicarilla Apache 

Nation, Navajo Nation, San Juan Pueblo, Pueblo of 

Acoma, Pueblo of Jemez, Pueblo of Laguna, Pueblo of 

Ildefonso, Pueblo of Santa Ana, Pueblo of Santa Clara, 

Pueblo of Taos, Pueblo of Zuni, Southern Ute Tribe, 

Uintah and Ouray Ute Indian Tribe, and Ute Mountain Ute Tribe) were invited to take part or formally 

consult in the planning process. The Service’s regional 

archaeologist consulted with the State Historic Preservation Officer, and was intimately involved with 

the development of this EA. Some nongovernmental 

organizations that are active in and around the San 

Luis Valley were also consulted, including Colorado 

Cattleman’s Agricultural Land Trust, Colorado Open 

Lands, Colorado Water Trust, Ducks Unlimited, The 

Nature Conservancy, Orient Land Trust, Rio Grande 

Headwaters Land Trust, and Trust for Public Land.

The Service coordinated internally in the development of this EA as well. Region 6 refuge planning 

staff and San Luis Valley National Wildlife Refuge 

Complex staff conducted the analysis and prepared 

this document, as well as the LPP. An intra-Service 

Endangered Species Act section 7 consultation was conducted and resulted in a finding of “May affect but not 

likely to affect” for Endangered Species Act–protected 

or candidate species (appendix E). Region 6 Migratory Birds staff guided the development of our focal 

species list, and both that office and staff from the 

Region 6 Fisheries office reviewed the document (See 

“Appendix B—List of Preparers and Reviewers”).

Contaminants and 

Hazardous Waste

The Service is required to invest in healthy lands. 

At a minimum, a level 1 pre-acquisition site assessment by the Service’s Ecological Services, Colorado 

Field Office or New Mexico Field Office, as appropriate, would be required before acquisition.

National Environmental 

Policy Act

The Service conducted this analysis under the 

authority of and in compliance with NEPA, which 

requires an evaluation of reasonable alternatives that 

will meet stated objectives, and an assessment of the 

possible effects on the natural and human environment.

Environmental Assessment

The EA will be the basis for determining whether 

the implementation of the proposed action would constitute a major Federal action significantly affecting 

the quality of natural and human environments. It 

involved other government agencies and the public in 

naming issues and alternatives for the project.

Distribution and Availability

The Service made available this final EA (with the 

associated LPP in the same volume) to the project mailing list, which includes Federal and State legislative 

delegations; tribes; Federal, State, and local agencies; 

nongovernmental organizations; and interested individuals. Copies can be requested from the Service’s 

Region 6 office. The documents are also available electronically on the refuge planning Web site.

■ Project Web site: http://www.fws.gov/mountainprairie/refuges/slv.php

■ Project email: slvrefugesplanning@fws.gov

Region 6 Division of Biological Resources

Attn: SLVCA EA

Branch of Refuge Planning

U.S. Fish and Wildlife Service

P.O. Box 25486, Denver Federal Center

Denver, CO 80225

303 / 236 8132
Appendix B

List of Preparers and Reviewers

Author’s name Position Work unit

Mike Blenden Project leader USFWS, San Luis Valley Refuge Complex, Alamosa, CO

Mike Dixon Land protection planner USFWS, Region 6, Planning Division, Lakewood, CO

Mark Ely Geographic Information Systems 

specialist

USFWS, Region 6, Planning Division, Lakewood, CO

Meg Estep Chief, water resources USFWS, Region 6, Water Resources Division, Lakewood, CO

Lynne Koontz Economist USGS, Fort Collins Science Center, Policy and Science 

Analysis Assistance, Fort Collins, CO

Erik Larsen Student intern USGS, Fort Collins Science Center, Policy and Science 

Analysis Assistance, Fort Collins, CO

Leslie Richardson Economist USGS, Fort Collins Science Center, Policy and Science 

Analysis Assistance, Fort Collins, CO

Catherine M. Cullinane 

Thomas

Economist USGS, Fort Collins Science Center, Policy and Science 

Analysis Assistance, Fort Collins, CO

Meg Van Ness Regional archaeologist USFWS, Region 6, Archaeology Division, Alamosa, CO

Reviewer’s name Position Work unit

David Lucas Chief, Division of Refuge Planning USFWS, Region 6, Planning Division, Lakewood, CO

Brooke McDonald Writer-editor North State Resources, Inc., Redding, CA

Kathryn McDonald Managing writer-editor North State Resources, Inc., Redding, CA

Sue Oliveira Chief, Division of Realty USFWS, Region 6, Planning Division, Lakewood, CO

Laurie Shannon Conservation planner USFWS, Region 6, Planning Division, Lakewood, CO

Mitch Werner Writer-editor USFWS, Region 6, Planning Division, Lakewood, CO

Appendix C

Environmental Compliance

This appendix contains several environmental compliance documents:

■ finding of no significant impact

■ environmental action statement

■ environmental compliance certificate

■ Service Director’s approval
82 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Finding of No Significant Impact 

U.S. Department of the Interior, U.S. Fish and Wildlife Service

Region 6, Lakewood, Colorado 

San Luis Valley Conservation Area

Alamosa, Conejos, Costilla, Hinsdale, Mineral, Rio Grande, and Saguache Counties, Colorado

Rio Arriba and Taos Counties, New Mexico

The U.S. Fish and Wildlife Service (Service) has 

completed the San Luis Valley Conservation Area 

Land Protection Plan and Environmental Assessment. 

This planning process considered the authorization of 

a new unit of the National Wildlife Refuge System, the 

San Luis Valley Conservation Area. The Service conducted a National Environmental Policy Act (NEPA) 

review of the proposed easement program. The resulting environmental assessment (EA) evaluates two 

alternatives—alternative A, a no-action alternative; 

and alternative B, the preferred alternative—to 

establish the San Luis Valley Conservation Area. 

Alternative B, the preferred alternative, was 

selected for implementation because it best meets the 

Service’s mission to sustain fish and wildlife populations and to conserve a network of lands that provide 

their habitats. The San Luis Valley Conservation 

Area will use conservation easements, with limited 

fee-title acquisition where it benefits the management of existing refuges, to conserve these habitats 

in a working agricultural landscape by maintaining 

current land management practices while preventing 

the conversion of native vegetation to other uses. In 

so doing, this project will protect habitat for Federal 

trust species of wildlife, the water quality of the 

upper Rio Grande, and the rural agricultural aesthetic 

that defines the region. 

PUBLIC INVOLVEMENT

As part of the public scoping process associated 

with this action, comments were solicited from the 

public through news releases and public meetings. 

On March 15, 2011, a news release was issued by the 

USFWS Region 6, which announced the beginning of 

the NEPA review and solicited scoping comments from 

the public. Public scoping meetings were held March 

29, 30, and 31, 2012 in Alamosa, Monte Vista, and Moffat, Colorado, respectively. Everyone in attendance 

was given an opportunity to express their ideas and 

concerns. Approximately 50 people attended these 

meetings, and an additional 14 written comments were 

received and used to define the scope of the NEPA 

review and identify potential issues. On January 

4, 2012, in Alamosa, Colorado, the Secretary of the 

Interior held a public and media event to highlight 

San Luis Valley projects under the America’s Great 

Outdoors initiative, of which the San Luis Valley Conservation Area was a component. This was followed by 

a news release on May 9, 2012, which announced the 

release of a draft EA and land protection plan (LPP) 

for 30 days of public comment. Formal public meetings 

were held on May 14, 15, and 16, 2012, in Alamosa, San 

Luis, and Moffat, Colorado, respectively. The public 

comment period ended on June 8, 2012. In addition to 

comments presented by some of the approximately 

50 people who attended these meetings, another 14 

written comments were received from individuals, 

nongovernmental organizations, and agencies. Public 

comments and responses are in appendix D of the LPP.

EFFECTS OF THE PROPOSED ACTION

The EA has taken a hard look at the environmental impacts to inform the public and ourselves about 

the consequences of the proposed action (the Service’s 

preferred alternative).

In determining whether this project is a major 

action significantly affecting the quality of the human 

environment, we looked at both the context and intensity of the action (40 CFR § 1508.27, 40 CFR § 

1508.14) as required by NEPA. In terms of context, 

the preferred alternative will occur in the San Luis 

Valley in south-central Colorado and north-central New 

Mexico, but we have evaluated whether it will have 

effects on the human environment on a broader scale. 

The project will be implemented over time, dependent 

on the Service’s ability to obtain funding needed for 

easement acquisition. Of the roughly 4.2 million acres 

within the overall project boundary, easements may 

be purchased by the Service only from willing sellers 

on a strictly voluntary basis on up to 250,000 acres, 

plus up to 30,000 acres of fee title purchased from 

willing sellers. Because the human environment is 

interpreted by NEPA to mean the natural and physical environment and the relationship of people with 

that environment (40 CFR § 1508.14), in addition 

to our thorough analysis of physical environmental 
Appendix C—Environmental Compliance 83

effects, we carefully assessed the manner in which 

the local people and natural resources relate to the 

environment in the San Luis Valley, though economic 

or social effects are not intended by themselves to 

require the preparation of an environmental impact 

statement (40 CFR § 1508.14). 

Establishment of the San Luis Valley Conservation 

Area will enable the Service to seek permanent protection for important wildlife habitat for federal trust 

species including the federally endangered southwestern willow flycatcher, the federally threatened Gunnison sage-grouse, and migratory birds such as Wilson’s 

phalarope and American bittern, as well as more than 

300 other species of birds. This protection will also 

positively benefit state-managed species such as elk.

Conservation easements in the San Luis Valley 

Conservation Area will increase the capacity for ecosystems in that region to adapt to climate change and 

increase their resiliency to temporary environmental 

disturbances such as drought and fire. These benefits 

will result from ensuring connectivity between permanently protected areas within and around the conservation area, which will allow migration and colonization by 

variants better adapted to changing conditions. Easements will also prevent the negative local effects of 

habitat fragmentation resulting from land cover changes 

due to subdivision and infrastructure development.

The easements will be a source of capital for local 

landowners. It is likely that much of this money will 

be reinvested locally, so easements in the San Luis 

Valley Conservation Area may be a one-time positive 

benefit to the local economy. By placing restrictions 

on where willing landowners could build structures, 

the San Luis Valley Conservation Area will affect the 

location and distribution, but not the rate or density, 

of human population growth in the project area. There 

may be benefits to nonparticipating landowners due 

to the preservation of habitat that may provide for 

wildlife-dependent recreation off easement lands and 

due to the preservation of the open-space aesthetic 

on participating properties. The purchase of an easement will reduce the sale value of a property, which 

could result in a minor reduction in tax revenues if the 

land was being taxed on its market, rather than agricultural value. However, such reduction in revenue 

is likely to be more than offset by a reduction in local 

government costs associated with providing services 

to lands converted to residential development.

The establishment of the San Luis Valley Conservation Area will not impact how other State and Federal 

agencies manage their lands or how they allot permits 

for things such as grazing on public lands. The purchase 

of an easement will not affect the rights of third parties to exercise their preexisting legal rights on that 

property (for example, third-party mineral owners).

Unless explicitly stated in the easement due to the 

requirement of a participating land owner, the San 

Luis Valley Conservation Area will not necessarily 

preclude the development of certain energy infrastructure. The proposed development will be subject 

to a compatibility determination by the refuge manager. If the proposed development was found compatible, the Service would work with the landowner and 

developer to minimize the negative environmental 

effects of the development. 

Conservation easements purchased on private land 

will not change the landowners’ rights to manage public access to their properties. Private landowners will 

retain full control over their property access rights, 

including allowing or restricting recreational access.

DECISION AND FINDING OF NO 

SIGNIFICANT IMPACT

The analysis indicates that there will not be a 

significant impact1, individually or cumulatively, on 

the quality of the human environment2 as a result 

of this proposed action. I agree with this conclusion 

and therefore find that an EIS need not be prepared. 

This determination is based on the following factors:

1. Environmental consequences will be beneficial to 

wildlife habitat, migratory bird populations, and 

water quality. Based on informal intra-Service 

section 7 consultation, the proposed action will 

not result in the jeopardy of any federally threatened or endangered species, or adversely modify 

existing designated critical habitat. The proposed 

conservation area may permanently protect tens 

of thousands of acres of habitat for Endangered 

Species Act listed and candidate species.

2. The proposed action will pose no known risk to 

public health and safety. 

3. The effects on the quality of the human environment are not highly controversial. There is the 

potential for some restriction in the potential siting 

1

 40 CFR § 1508.27 “Significantly” as used in NEPA requires 

considerations of both context and intensity: (a) Context. This 

means that the significance of an action must be analyzed in several 

contexts such as society as a whole (human, national), the affected 

region, the affected interests, and the locality. Significance varies 

with the setting of the proposed action. For instance, in the case 

of a site-specific action, significance would usually depend upon 

the effects in the locale rather than in the world as a whole. Both 

short- and long-term effects are relevant; and (b) Intensity. This 

refers to the severity of impact. Responsible officials must bear in 

mind that more than one agency may make decisions about partial 

aspects of a major action.

2

 40 CFR § 1508.14 “Human environment” shall be interpreted 

comprehensively to include the natural and physical environment and 

the relationship of people with that environment. (See the definition 

of “effects” (40 CFR § 1508.8).) This means that economic or social 

effects are not intended by themselves to require preparation of an 

environmental impact statement. When an environmental impact 

statement is prepared and economic or social and natural or physical 

environmental effects are interrelated, then the environmental 

impact statement will discuss all of these effects on the human 

environment.
84 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

for energy infrastructure, but there is unlikely 

to be substantial conflict over this land use issue 

because the San Luis Valley Conservation Area 

easement program is a voluntary initiative with 

willing sellers only.

4. The proposed easements will not affect districts, 

sites, highways, structures, or objects listed in 

or eligible for listing in the National Register of 

Historic Places, nor will they likely cause any loss 

or destruction of significant scientific, cultural, or 

historic resources. 

5. No significant cumulative effects were identified 

through this assessment. The EA discussed the 

cumulative effects on and off the refuge with those 

actions proposed by others.

6. The proposed action will be in compliance with all 

federal, state, and local laws.

Therefore, in light of the compelling science in support of the project, and my review of the information 

contained in the supporting reference, I have determined that authorizing the San Luis Valley Conservation Area is not a major Federal action that would 

significantly affect the quality of the human environment within the meaning of Section 102(2)(C) of NEPA.

The Finding of No Significant Impact and supporting NEPA analysis will be available to the public on request. Copies of the EA are available for all 

affected landowners, agencies, private groups, and 

other interested parties. These documents are on file 

at the U.S. Fish and Wildlife Service, National Wildlife Refuge System, Division of Refuge Planning, P.O. 

Box 25486–DFC, Denver, Colorado 80225 (telephone: 

303 / 236 8145). 

SUPPORTING REFERENCE

U.S. Fish and Wildlife Service. 2015. Land protection plan 

for the San Luis Valley Conservation Area. Lakewood, CO: U.S. 

Department of the Interior, U.S. Fish and Wildlife 

Service. 151 p.
Appendix C—Environmental Compliance 85

Environmental Action Statement 

U.S. Department of the Interior, U.S. Fish and Wildlife Service

Region 6, Lakewood, Colorado 

Within the spirit and intent of the Council on Environmental Quality’s regulations for implementing the National Environmental Policy Act and other statutes, orders, and policies that protect fish and wildlife resources, 

I have established the following administrative record and have determined that the action to establish the San 

Luis Valley Conservation Area and associated easement and land acquisition program:

____ is a categorical exclusion as provided by 516 DM 2, appendices 1 and 2, and 516 DM 6, appendix 1. 

No further documentation will be made.

_X_ is found not to have significant environmental effects as determined by the attached Finding of 

No Significant Impact and environmental assessment.

____ is found to have special environmental conditions as described in the attached environmental 

assessment. The attached Finding of No Significant Impact will not be final nor any actions taken 

pending a 30-day period for public review [40 CFR 1501.4(e)(2)].

____ is found to have significant effects and, therefore, a notice of intent will be published in the 

Federal Register to prepare an environmental impact statement before the project is considered 

further.

____ is denied because of environmental damage, Service policy, or mandate.

____ is an emergency situation. Only those actions necessary to control the immediate impacts of the 

emergency will be taken. Other related actions remain subject to National Environmental Policy 

Act review.

Other supporting document: U.S. Fish and Wildlife Service. 2015. Land protection plan for the San Luis Valley Conservation Area. Lakewood, CO: U.S. 

Department of the Interior, U.S. Fish and Wildlife Service. 151 p.

Will Meeks Date

Assistant Regional Director

National Wildlife Refuge System, Region 6

Lakewood, Colorado
86 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Environmental Compliance Certificate 

U.S. Department of the Interior, U.S. Fish and Wildlife Service

Region 6, Lakewood, Colorado 

Project: San Luis Valley Conservation Area

State: Colorado and New Mexico

Action (indicate if not applicable) Date

National Environmental Policy Act (indicate one)

Categorical Exclusion N/A

Environmental Assessment and Finding of No Significant Impact 3/19/2015

Environmental Impact Statement and Record of Decision N/A

Executive Order 11593—Protection of Historical, Archaeological, and Scientific Properties 8/1/2012

Executive Order 11988—Floodplain Management 8/1/2012

Executive Order 11990—Protection of Wetlands 8/1/2012

Executive Order 12372—Intergovernmental Review of Federal Programs 8/1/2012

Executive Order 12898—Federal Actions to Address Environmental Justice in Minority and

Low-Income Populations 8/1/2012

Executive Order 12996—Management and General Public Use of the National Wildlife Refuge 

System 8/1/2012

Endangered Species Act, Section 7 6/28/2012

Coastal Zone Management Act, Section 307 N/A

Uniform Relocation Assistance and Real Property Acquisition Policies Act Various

Level 1 Contaminants and Hazardous Waste (Secretarial Order 3127: 602 DM 2) Various

I hereby certify that all requirements of the law, rules, and Service regulations or policies applicable to planning 

for the above project have met with compliance. I approve the establishment of the San Luis Valley Conservation Area to be administered and managed as part of the National Wildlife Refuge System.
Appendix C—Environmental Compliance 87

Statement of Compliance

The following Executive orders and legislative acts 

have been reviewed as they apply to the establishment 

of the San Luis Valley Conservation Area:

1. Executive Order 11593—Protection of Historical, 

Archaeological, and Scientific Properties. Per the 

regional archaeologist, the creation of this document constitutes an “undertaking” as defined by the 

National Historic Preservation Act (36 CFR 800.16(y)). 

It is an undertaking that has no potential to cause 

effects on historic properties and therefore there 

are no further review obligations under the act. If, 

in the future, there are undertakings planned that 

would potentially cause adverse effects on historic 

properties, including ground disturbance or alterations to buildings or structures over 50 years of 

age, those projects should be reviewed under section 106 of the act before the start of the project.

2. Executive Order 11988—Floodplain Management. No structures that could be damaged by or 

that would significantly influence the movement 

of floodwater are planned for construction by the 

U.S. Fish and Wildlife Service on land acquired as 

part of this project.

3. Executive Order 11990—Protection of Wetlands. 

Conveyance of the lands and interests herein 

shall not exempt such lands and interests from all 

Federal, State, and local laws and regulations as 

applicable thereto by virtue of their characteristics as wetlands, subject to Executive Order 11990 

(May 24, 1990).

4. Executive Order 12372—Intergovernmental Review. The Service has discussed or offered to discuss the proposal to establish the San Luis Valley 

Conservation Area with landowners; conservation 

organizations; State, Federal, and county agencies; 

tribes; and other interested groups and individuals. 

At the Federal level, the Service staff has coordinated with the U.S. Forest Service, the Bureau 

of Land Management, the National Park Service, 

and the Natural Resource Conservation Service, 

as well as the congressional delegations for the 

affected region. At the State level, the Service 

has worked with the Colorado Water Conservation Board and Colorado Parks and Wildlife. The 

Service has consulted representatives from local 

governments including Costilla County, Colorado, 

and Taos County, New Mexico. In addition, the 

Service has provided information to seventeen 

tribes with potential interest in this project.

5. Executive Order 12898—Federal Actions to Address Environmental Justice in Minority and 

Low-Income Populations. Establishing the San 

Luis Valley Conservation Area will not have a 

disproportionately high or adverse human health 

or environmental effect on minority or low-income 

populations. Therefore, this action complies with 

this Executive order.

6. Executive Order 12996—Management and General Public Use of the National Wildlife Refuge 

System. The public has been invited to participate 

in the planning process and has been very engaged. 

The Service held three public scoping meetings and 

three public comment meetings, and released the 

draft environmental assessment and land protection plan for 30 days to get input on the project. The 

Service received four written public comments on 

the draft EA. Comments and issues raised by the 

public have been incorporated into the EA and a copy 

of the final document will be sent to all interested 

landowners, agencies, private groups, and other 

parties. While the San Luis Valley Conservation 

Area will be, by definition, a unit of the National 

Wildlife Refuges System, the project is largely 

focused on conservation easements, and the Service 

will not manage or have control over public access 

to private lands. This right will remain with the 

private landowner. Management of any fee-title 

lands purchased or donated will be in accordance 

with the comprehensive conservation plan for the 

San Luis Valley National Wildlife Refuge Complex.

7. Endangered Species Act, section 7. An informal intraService section 7 consultation with the Ecological 

Services field offices in Colorado and New Mexico 

concluded with their concurrence that the establishment of the San Luis Valley Conservation Area may 

affect, but is not likely to adversely affect, species 

protected under the Endangered Species Act.

8. Coastal Zone Management Act. Due to the location of the project area, compliance with this act 

was determined not to be needed. 

9. Uniform Relocation Assistance and Real Property 

Acquisition Policies Act. The relevant portions of 

the act relating to tax reimbursements, etc., will be 

implemented on a case-by-case basis as appropriate.

10.Secretarial Order 3127—Contaminants and Hazardous Waste. A level 1 pre-acquisition contaminant survey will be completed before the purchase 

of any easement. 
88 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

I hereby certify that the Service has complied with all requirements of law, rules, or regulations applicable 

to pre-acquisition planning for the above project. I approve the establishment of an acquisition boundary for 

the San Luis Valley Conservation Area and the subsequent acquisition of up to 250,000 acres of easements and 

30,000 acres of fee-title from willing sellers.
Appendix C—Environmental Compliance 89

Service Director’s Approval

Appendix D

Species List for the San Luis Valley Conservation Area

Sources: Colorado Natural Diversity Information Source, San Luis Valley National Wildlife Refuge Complex Species List, USGS 

Nonindigenous Aquatic Species Database, NRCS Plants Database.

* Nonnative (Because of the number of plant species in the project area, introduced plants are not shown).

Scientific name Common name Status

Birds

Recurvirostra americana American avocet

Botaurus lentiginosus American bittern

Fulica americana American coot

Corvus brachyrhynchos American crow

Cinclus mexicanus American dipper

Carduelis tristis American goldfinch

Pluvialis dominica American golden plover

Falco sparverius American kestrel

Falco peregrinus anatum American peregrine falcon

Anthus rubescens American pipit

Turdus migratorius American robin

Spizella arborea American tree sparrow

Pelecanus erythrorhynchos American white pelican

Anas americana American wigeon

Calypte anna Anna’s hummingbird

Gavia arctica Arctic loon

Myiarchus cinerascens Ash-throated flycatcher

Calidris bairdii Baird’s sandpiper

Haliaeetus leucocephalus Bald eagle State special concern

Columba fasciata Band-tailed pigeon

Riparia riparia Bank swallow

Tyto alba Barn owl

Hirundo rustica Barn swallow

Bucephala islandica Barrow’s goldeneye

Ceryle alcyon Belted kingfisher

Thryomanes bewickii Bewick’s wren

Sayornis nigricans Black phoebe

Leucosticte atrata Black rosy finch

Cypseloides niger Black swift

Chlidonias niger Black tern

Mniotilta varia Black-and-white warbler

Pluvialis squatarola Black-bellied plover

Pica pica Black-billed magpie

Poecile atricapillus Black-capped chickadee
92 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Archilochus alexandri Black-chinned hummingbird

Nycticorax nycticorax Black-crowned night-heron

Pheucticus melanocephalus Black-headed grosbeak

Himantopus mexicanus Black-necked stilt

Dendroica striata Blackpoll warbler

Dendroica caerulescens Black-throated blue warbler

Dendroica nigrescens Black-throated gray warbler

Amphispiza bilineata Black-throated sparrow

Guiraca caerulea Blue grosbeak

Dendragapus obscurus Blue grouse

Cyanocitta cristata Blue jay

Polioptila caerulea Blue-gray gnatcatcher

Anas discors Blue-winged teal

Dolichonyx oryzivorus Bobolink

Bombycilla garrulus Bohemian waxwing

Larus philadelphia Bonaparte’s gull

Aegolius funereus Boreal owl

Euphagus cyanocephalus Brewer’s blackbird

Spizella breweri Brewer’s sparrow

Selasphorus platycercus Broad-tailed hummingbird

Certhia americana Brown creeper

Toxostoma rufum Brown thrasher

Leucosticte australis Brown-capped rosy finch

Molothrus ater Brown-headed cowbird

Bucephala albeola Bufflehead

Icterus bullockii Bullock’s oriole

Athene cunicularia Burrowing owl State threatened

Psaltriparus minimus Bushtit

Branta hutchinsii Cackling goose

Larus californicus California gull

Stellula calliope Calliope hummingbird

Branta canadensis Canada goose

Aythya valisineria Canvasback

Pipilo fuscus Canyon towhee

Catherpes mexicanus Canyon wren

Hydroprogne caspia Caspian tern

Carpodacus cassinii Cassin’s finch

Tyrannus vociferans Cassin’s kingbird

Aimophila cassinii Cassin’s sparrow

Bubulcus ibis Cattle egret

Bombycilla cedrorum Cedar waxwing

Dendroica pensylvanica Chestnut-sided warbler

Corvus cryptoleucus Chihuahuan raven

Spizella passerina Chipping sparrow

Anas cyanoptera Cinnamon teal
Appendix D—Species List for the San Luis Valley Conservation Area 93

Scientific name Common name Status

Aechmophorus clarkii Clark’s grebe

Nucifraga columbiana Clark’s nutcracker

Spizella pallida Clay-colored sparrow

Petrochelidon pyrrhonota Cliff swallow

Bucephala clangula Common goldeneye

Quiscalus quiscula Common grackle

Gavia immer Common loon

Mergus merganser Common merganser

Chordeiles minor Common nighthawk

Phalaenoptilus nuttallii Common poorwill

Corvus corax Common raven

Carduelis flammea Common redpoll

Gallinago gallinago Common snipe

Sterna hirundo Common tern

Geothlypis trichas Common yellowthroat

Accipiter cooperii Cooper’s hawk

Empidonax occidentalis Cordilleran flycatcher

Junco hyemalis Dark-eyed junco

Spiza americana Dickcissel

Phalacrocorax auritus Double-crested cormorant

Picoides pubescens Downy woodpecker

Empidonax oberholseri Dusky flycatcher

Dendragapus obscurus Dusky grouse

Podiceps nigricollis Eared grebe

Tyrannus tyrannus Eastern kingbird

Streptopelia decaocto Eurasian collared-dove*

Sturnus vulgaris European starling*

Coccothraustes vespertinus Evening grosbeak

Buteo regalis Ferruginous hawk State special concern

Otus flammeolus Flammulated owl

Sterna forsteri Forster’s tern

Passerella iliaca Fox sparrow

Larus pipixcan Franklin’s gull

Anas strepera Gadwall

Callipepla gambelii Gambel’s quail

Larus glaucescens Glaucous-winged gull

Aquila chrysaetos Golden eagle

Regulus satrapa Golden-crowned kinglet

Dendroica graciae Grace’s warbler

Ammodramus savannarum Grasshopper sparrow

Dumetella carolinensis Gray catbird

Empidonax wrightii Gray flycatcher

Perisoreus canadensis Gray jay

Leucosticte tephrocotis Gray-crowned rosy finch

Ardea herodias Great blue heron
94 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Ardea alba Great egret

Bubo virginianus Great horned owl

Geococcyx californianus Greater roadrunner

Grus canadensis tabida Greater sandhill crane State special concern

Aythya marila Greater scaup

Anser albifrons Greater white-fronted goose

Tringa melanoleuca Greater yellowlegs

Quiscalus mexicanus Great-tailed grackle

Butorides virescens Green heron

Pipilo chlorurus Green-tailed towhee

Anas crecca Green-winged teal

Centrocercus minimus Gunnison sage-grouse Federally endangered

Picoides villosus Hairy woodpecker

Empidonax hammondii Hammond’s flycatcher

Zonotrichia querula Harris’ sparrow

Catharus guttatus Hermit thrush

Larus argentatus Herring gull

Lophodytes cucullatus Hooded merganser

Podiceps auritus Horned grebe

Eremophila alpestris Horned lark

Carpodacus mexicanus House finch

Passer domesticus House sparrow*

Troglodytes aedon House wren

Passerina cyanea Indigo bunting

Baeolophus griseus Juniper titmouse

Charadrius vociferus Killdeer

Calcarius lapponicus Lapland longspur

Calamospiza melanocorys Lark bunting

Chondestes grammacus Lark sparrow

Passerina amoena Lazuli bunting

Ixobrychus exilis Least bittern

Empidonax minimus Least flycatcher

Calidris minutilla Least sandpiper

Sternula antillarum Least tern Federally and State endangered

Carduelis psaltria Lesser goldfinch

Aythya affinis Lesser scaup

Tringa flavipes Lesser yellowlegs

Melanerpes lewis Lewis’ woodpecker

Melospiza lincolnii Lincoln’s sparrow

Egretta caerulea Little blue heron

Lanius ludovicianus Loggerhead shrike

Numenius americanus Long-billed curlew State special concern

Limnodromus scolopaceus Long-billed dowitcher

Asio otus Long-eared owl

Oporornis tolmiei MacGillivray’s warbler
Appendix D—Species List for the San Luis Valley Conservation Area 95

Scientific name Common name Status

Eugenes fulgens Magnificent hummingbird

Anas platyrhynchos Mallard

Limosa fedoa Marbled godwit

Cistothorus palustris Marsh wren

Falco columbarius Merlin

Strix occidentalis lucida Mexican spotted owl Federally and State threatened

Sialia currucoides Mountain bluebird

Poecile gambeli Mountain chickadee

Charadrius montanus Mountain plover State special concern

Zenaida macroura Mourning dove

Vermivora ruficapilla Nashville warbler

Cardinalis cardinalis Northern cardinal

Colaptes auratus Northern flicker

Accipiter gentilis Northern goshawk

Circus cyaneus Northern harrier

Mimus polyglottos Northern mockingbird

Parula americana Northern parula

Anas acuta Northern pintail

Glaucidium gnoma Northern pygmy-owl

Stelgidopteryx serripennis Northern rough-winged swallow

Aegolius acadicus Northern saw-whet owl

Anas clypeata Northern shoveler

Lanius excubitor Northern shrike

Seiurus noveboracensis Northern waterthrush

Contopus cooperi Olive-sided flycatcher

Vermivora celata Orange-crowned warbler

Pandion haliaetus Osprey

Seiurus aurocapillus Ovenbird

Gavia pacifica Pacific loon

Calidris melanotos Pectoral sandpiper

Falco peregrinus Peregrine falcon State special concern

Podilymbus podiceps Pied-billed grebe

Pinicola enucleator Pine grosbeak

Carduelis pinus Pine siskin

Gymnorhinus cyanocephalus Pinyon jay

Vireo plumbeus Plumbeous vireo

Falco mexicanus Prairie falcon

Porphyrio martinica Purple gallinule

Progne subis Purple martin

Sitta pygmaea Pygmy nuthatch

Loxia curvirostra Red crossbill

Mergus serrator Red-breasted merganser

Sitta canadensis Red-breasted nuthatch

Vireo olivaceus Red-eyed vireo

Aythya americana Redhead
96 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Melanerpes erythrocephalus Red-headed woodpecker

Sphyrapicus nuchalis Red-naped sapsucker

Phalaropus lobatus Red-necked phalarope

Buteo jamaicensis Red-tailed hawk

Agelaius phoeniceus Red-winged blackbird

Larus delawarensis Ring-billed gull

Aythya collaris Ring-necked duck

Phasianus colchicus Ring-necked pheasant*

Columba livia Rock pigeon*

Salpinctes obsoletus Rock wren

Pheucticus ludovicianus Rose-breasted grosbeak

Chen rossii Ross’ goose

Buteo lagopus Rough-legged hawk

Regulus calendula Ruby-crowned kinglet

Oxyura jamaicensis Ruddy duck

Selasphorus rufus Rufous hummingbird

Aimophila ruficeps Rufous-crowned sparrow

Xema sabini Sabine’s gull

Centrocercus urophasianus Sage-grouse

Amphispiza belli Sage sparrow

Oreoscoptes montanus Sage thrasher

Calidris alba Sanderling

Grus canadensis Sandhill crane

Passerculus sandwichensis Savannah sparrow

Sayornis saya Say’s phoebe

Tyrannus forficatus Scissor-tailed flycatcher

Cistothorus platensis Sedge wren

Charadrius semipalmatus Semipalmated plover

Calidris pusilla Semipalmated sandpiper

Accipiter striatus Sharp-shinned hawk

Limnodromus griseus Short-billed dowitcher

Asio flammeus Short-eared owl

Chen caerulescens Snow goose

Egretta thula Snowy egret

Charadrius alexandrinus Snowy plover State special concern

Tringa solitaria Solitary sandpiper

Melospiza melodia Song sparrow

Porzana carolina Sora

Empidonax traillii extimus Southwestern willow flycatcher Federally and State endangered

Strix occidentalis Spotted owl

Actitis macularia Spotted sandpiper

Pipilo maculatus Spotted towhee

Cyanocitta stelleri Steller’s jay

Calidris himantopus Stilt sandpiper

Melanitta perspicillata Surf scoter
Appendix D—Species List for the San Luis Valley Conservation Area 97

Scientific name Common name Status

Piranga rubra Summer tanager

Buteo swainsoni Swainson’s hawk

Catharus ustulatus Swainson’s thrush

Melospiza georgiana Swamp sparrow

Vermivora peregrina Tennessee warbler

Picoides tridactylus Three-toed woodpecker

Myadestes townsendi Townsend’s solitaire

Dendroica townsendi Townsend’s warbler

Tachycineta bicolor Tree swallow

Cygnus columbianus Tundra swan

Cathartes aura Turkey vulture

Ixoreus naevius Varied thrush

Catharus fuscescens Veery

Pyrocephalus rubinus Vermilion flycatcher

Pooecetes gramineus Vesper sparrow

Tachycineta thalassina Violet-green swallow

Rallus limicola Virginia rail

Vermivora virginiae Virginia’s warbler

Vireo gilvus Warbling vireo

Sialia mexicana Western bluebird

Athene cunicularia Western burrowing owl

Aechmophorus occidentalis Western grebe

Tyrannus verticalis Western kingbird

Sturnella neglecta Western meadowlark

Calidris mauri Western sandpiper

Otus kennicottii Western screech-owl

Aphelocoma californica Western scrub jay

Charadrius alexandrinus nivosus Western snowy plover

Piranga ludoviciana Western tanager

Contopus sordidulus Western wood-pewee

Numenius phaeopus Whimbrel

Eudocimus albus White ibis

Sitta carolinensis White-breasted nuthatch

Zonotrichia leucophrys White-crowned sparrow

Plegadis chihi White-faced ibis

Calidris fuscicollis White-rumped sandpiper

Lagopus leucurus White-tailed ptarmigan

Zonotrichia albicollis White-throated sparrow

Aeronautes saxatalis White-throated swift

Loxia leucoptera White-winged crossbill

Melanitta fusca White-winged scoter

Meleagris gallopavo Wild turkey

Grus americana Whooping crane Federally and State endangered

Catoptrophorus semipalmatus Willet

Sphyrapicus thyroideus Williamson’s sapsucker
98 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Empidonax traillii Willow flycatcher

Phalaropus tricolor Wilson’s phalarope

Gallinago delicata Wilson’s snipe

Wilsonia pusilla Wilson’s warbler

Aix sponsa Wood duck

Helmitheros vermivorum Worm-eating warbler

Hylocichla mustelina Wood thrush

Dendroica petechia Yellow warbler

Coccyzus americanus Yellow-billed cuckoo Federally threatened

Icteria virens Yellow-breasted chat

Xanthocephalus xanthocephalus Yellow-headed blackbird

Dendroica coronata Yellow-rumped warbler

Amphibians

Bufo boreas boreas Boreal toad State endangered

Rana catesbeiana Bullfrog*

Hyla arenicolor Canyon treefrog

Bufo cognatus Great Plains toad

Spea multiplicata New Mexico spadefoot

Rana pipiens Northern leopard frog State special concern

Spea bombifrons Plains spadefoot

Ambystoma tigrinum Tiger salamander

Pseudacris triseriata Western chorus frog

Bufo woodhousii Woodhouse’s toad

Mammals

Sciurus aberti Abert’s squirrel

Taxidea taxus American badger

Castor canadensis American beaver

Cervus elaphus American elk

Martes americana American marten

Ochotona princeps American pika

Eptesicus fuscus Big brown bat

Ovis canadensis Bighorn sheep

Ursus americanus Black bear

Mustela nigripes Black-footed ferret Federally and State endangered

Lepus californicus Black-tailed jackrabbit

Lynx rufus Bobcat

Thomomys bottae Botta’s pocket gopher State special concern

Tadarida brasiliensis Brazilian free-tailed bat

Neotoma cinerea Bushy-tailed woodrat

Tamias quadrivittatus Colorado chipmunk

Conepatus mesoleucus Common hog-nosed skunk

Ondatra zibethicus Common muskrat

Erethizon dorsatum Common porcupine

Canis latrans Coyote

Peromyscus maniculatus Deer mouse
Appendix D—Species List for the San Luis Valley Conservation Area 99

Scientific name Common name Status

Sylvilagus audubonii Desert cottontail

Mustela erminea Ermine

Myotis thysanodes Fringed myotis

Spermophilus lateralis Golden-mantled ground squirrel

Urocyon cinereoargenteus Gray fox

Cynomys gunnisoni Gunnison’s prairie dog

Phenacomys intermedius Heather vole

Lasiurus cinereus Hoary bat

Mus musculus House mouse*

Tamias minimus Least chipmunk

Myotis lucifugus Little brown myotis

Myotis evotis Long-eared myotis

Myotis volans Long-legged myotis

Microtus longicaudus Long-tailed vole

Mustela frenata Long-tailed weasel

Lynx canadensis Canada lynx Federally threatened, State endangered

Sorex cinereus Masked shrew

Microtus pennsylvanicus Meadow vole

Neotoma mexicana Mexican woodrat

Mustela vison Mink

Sorex monticolus Montane shrew

Microtus montanus Montane vole

Alces alces Moose

Sylvilagus nuttallii Mountain cottontail

Oreamnos americanus Mountain goat

Felis concolor Mountain lion

Odocoileus hemionus Mule deer

Onychomys leucogaster Northern grasshopper mouse

Thomomys talpoides Northern pocket gopher State special concern

Lutra canadensis Northern river otter

Peromyscus nasutus Northern rock mouse

Dipodomys ordii Ord’s kangaroo rat

Tamiasciurus hudsonicus Pine squirrel

Perognathus flavescens Plains pocket mouse

Antilocapra americana Pronghorn

Procyon lotor Raccoon

Vulpes vulpes Red fox

Bassariscus astutus Ringtail

Perognathus flavus Silky pocket mouse

Lasionycteris noctivagans Silver-haired bat

Lepus americanus Snowshoe hare

Clethrionomys gapperi Southern red-backed vole

Mephitis mephitis Striped skunk

Spermophilus tridecemlineatus Thirteen-lined ground squirrel

Plecotus townsendii Townsend’s big-eared bat State special concern
100 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Sorex palustris Water shrew

Reithrodontomys megalotis Western harvest mouse

Zapus princeps Western jumping mouse

Myotis ciliolabrum Western small-footed myotis

Spilogale gracilis Western spotted skunk

Odocoileus virginianus White-tailed deer

Lepus townsendii White-tailed jackrabbit

Gulo gulo Wolverine State endangered

Spermophilus elegans Wyoming ground squirrel

Marmota flaviventris Yellow-bellied marmot

Myotis yumanensis Yuma myotis

Reptiles

Sceloporus undulatus Fence lizard

Pituophis catenifer Gopher snake

Eumeces multivirgatus Many-lined skink

Crotalus viridis concolor Midget faded rattlesnake State special concern

Lampropeltis triangulum Milk snake

Phrynosoma hernandesi Short-horned lizard

Liochlorophis vernalis Smooth green snake

Eumeces gaigeae Variable skink

Crotalus viridis Western rattlesnake

Thamnophis elegans Western terrestrial garter snake

Fish

Anguilla rostrata American eel*

Thymallus arcticus Arctic grayling*

Ameiurus melas Black bullhead

Pomoxis nigromaculatus Black crappie*

Gymnocorymbus ternetzi Black tetra*

Ictalurus furcatus Blue catfish*

Oreochromis aureus Blue tilapia*

Lepomis macrochirus Bluegill*

Culaea inconstans Brook stickleback*

Salvelinus fontinalis Brook trout*

Salmo trutta Brown trout*

Ictalurus punctatus Channel catfish*

Oncorhynchus clarkii pleuriticus Colorado River cutthroat*

Cyprinus carpio Common carp*

Corydoras sp. Corydoras catfish*

Oncorhynchus clarkii × mykiss Cutbow trout (hybrid)*

Pimephales promelas Fathead minnow

Oncorhynchus clarkii carmichaeli Fine-spotted Snake River cutthroat*

Pylodictis olivaris Flathead catfish*

Platygobio gracilis Flathead chub*

Pterophyllum sp. Freshwater angelfish*

Oncorhynchus aguabonita Golden trout*
Appendix D—Species List for the San Luis Valley Conservation Area 101

Scientific name Common name Status

Carassius auratus Goldfish*

Ctenopharyngodon idella Grass carp*

Xiphophorus hellerii Green swordtail*

Lepomis cyanellus Green sunfish

Poecilia reticulata Guppy*

Hemigrammus ocellifer Head-and-taillight tetra*

Oncorhynchus nerka Kokanee*

Salvelinus namaycush Lake trout*

Salmo salar sebago Landlocked Atlantic salmon*

Micropterus salmoides Largemouth bass*

Rhinichthys cataractae Long-nose dace

Catostomus catostomus Longnose sucker*

Cottus bairdii Mottled sculpin*

Oreochromis mossambicus Mozambique tilapia*

Paracheirodon innesi Neon tetra*

Esox lucius Northern pike*

Fundulus zebrinus Plains killifish*

Fundulus sciadicus Plains topminnow*

Lepomis gibbosus Pumpkinseed*

Oncorhynchus mykiss Rainbow trout*

Symphysodon discus Red discus*

Gila pandora Rio Grande chub State special concern

Oncorhynchus clarki virginalis Rio Grande cutthroat trout State special concern

Catostomus plebeius Rio Grande sucker State endangered

Poecilia latipinna Sailfin molly*

Poecilia mexicana Shortfin molly*

Micropterus dolomieu Smallmouth bass*

Xiphophorus maculatus Southern platyfish*

Hypostomus sp. Suckermouth catfish*

Otocinclus sp. Suckermouth catfish*

Tinca tinca Tench*

Dorosoma petenense Threadfin shad*

Xiphophorus variatus Variable platyfish*

Pterygoplichthys disjunctivus Vermiculated sailfin*

Sander vitreus Walleye*

Lepomis gulosus Warmouth*

Oncorhynchus clarkii lewisi West slope cutthroat*

Gambusia affinis Western mosquitofish*

Catostomus commersonii White sucker*

Ameiurus natalis Yellow bullhead*

Perca flavescens Yellow perch*

Oncorhynchus clarkii bouvieri Yellowstone cutthroat*

Plants

Abies concolor White fir

Abies lasiocarpa Subalpine fir
102 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Abies lasiocarpa var. arizonica Corkbark fir

Abies lasiocarpa var. lasiocarpa Subalpine fir

Acer glabrum Rocky Mountain maple

Achillea millefolium Common yarrow

Achillea millefolium var. occidentalis Western yarrow

Achnatherum × bloomeri —

Achnatherum hymenoides Indian ricegrass

Achnatherum lettermanii Letterman’s needlegrass

Achnatherum nelsonii Columbia needlegrass

Achnatherum nelsonii ssp. nelsonii Columbia needlegrass

Achnatherum robustum Sleepygrass

Achnatherum scribneri Scribner needlegrass

Aconitum columbianum Columbian monkshood

Aconitum columbianum ssp. columbianum Columbian monkshood

Acroptilon repens Hardheads

Actaea rubra Red baneberry

Actaea rubra ssp. arguta Red baneberry

Adoxa moschatellina Muskroot

Agastache pallidiflora Bill Williams Mountain giant hyssop

Agastache pallidiflora ssp. pallidiflora Bill Williams Mountain giant hyssop

Agastache pallidiflora ssp. pallidiflora var. 

greenei

Bill Williams Mountain giant hyssop

Agoseris aurantiaca Orange agoseris

Agoseris glauca Pale agoseris

Agrostis exarata Spike bentgrass

Agrostis gigantea Redtop

Agrostis humilis Alpine bentgrass

Agrostis scabra Rough bentgrass

Agrostis variabilis Mountain bentgrass

Aletes anisatus Rocky Mountain Indian parsley

Aliciella pinnatifida Sticky gilia

Alisma gramineum Narrowleaf water plantain

Alisma triviale Northern water plantain

Allium cernuum Nodding onion

Allium geyeri Geyer’s onion

Allium geyeri var. tenerum Bulbil onion

Almutaster pauciflorus Alkali marsh aster

Alnus incana Gray alder

Alnus incana ssp. tenuifolia Thinleaf alder

Alopecurus aequalis Shortawn foxtail

Alopecurus aequalis var. aequalis Shortawn foxtail

Alopecurus alpinus Boreal alopecurus

Alyssum simplex Alyssum

Amaranthus albus Prostrate pigweed

Amaranthus blitoides Mat amaranth

Amaranthus retroflexus Redroot amaranth
Appendix D—Species List for the San Luis Valley Conservation Area 103

Scientific name Common name Status

Ambrosia acanthicarpa Flatspine bur ragweed

Amelanchier alnifolia Saskatoon serviceberry

Amelanchier alnifolia var. alnifolia Saskatoon serviceberry

Amelanchier utahensis Utah serviceberry

Amelanchier utahensis var. utahensis Utah serviceberry

Anaphalis margaritacea Western pearly everlasting

Androsace chamaejasme Sweetflower rockjasmine

Androsace chamaejasme ssp. carinata Sweetflower rockjasmine

Androsace occidentalis Western rockjasmine

Androsace septentrionalis Pygmyflower rockjasmine

Anemone canadensis Canadian anemone

Anemone multifida Pacific anemone

Angelica ampla Giant angelica

Angelica grayi Gray’s angelica

Antennaria anaphaloides Pearly pussytoes

Antennaria corymbosa Flat-top pussytoes

Antennaria marginata Whitemargin pussytoes

Antennaria media Rocky Mountain pussytoes

Antennaria microphylla Littleleaf pussytoes

Antennaria parvifolia Small-leaf pussytoes

Antennaria rosea Rosy pussytoes

Antennaria rosulata Kaibab pussytoes

Antennaria umbrinella Umber pussytoes

Apocynum androsaemifolium Spreading dogbane

Apocynum cannabinum Indianhemp

Aquilegia coerulea Colorado blue columbine

Aquilegia elegantula Western red columbine

Arabis × divaricarpa Spreadingpod rockcress

Arabis drummondii Drummond’s rockcress

Arabis fendleri Fendler’s rockcress

Arabis fendleri var. fendleri Fendler’s rockcress

Arabis gunnisoniana Gunnison’s rockcress

Arabis hirsuta Hairy rockcress

Arabis hirsuta var. pycnocarpa Creamflower rockcress

Arabis holboellii Holboell’s rockcress

Arabis holboellii var. pinetorum Holboell’s rockcress

Arabis lignifera Desert rockcress

Arabis oxylobula Glenwood Springs rockcress

Arctostaphylos uva-ursi Kinnikinnick

Arenaria fendleri Fendler’s sandwort

Arenaria fendleri var. fendleri Fendler’s sandwort

Arenaria hookeri Hooker’s sandwort

Arenaria hookeri ssp. hookeri Hooker’s sandwort

Arenaria lanuginosa Spreading sandwort

Arenaria lanuginosa ssp. saxosa Spreading sandwort
104 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Argentina anserina Silverweed cinquefoil

Argyrochosma fendleri Fendler’s false cloak fern

Aristida purpurea Purple threeawn

Aristida purpurea var. longiseta Fendler threeawn

Aristida purpurea var. purpurea Purple threeawn

Arnica chamissonis Chamisso arnica

Arnica chamissonis ssp. foliosa Chamisso arnica

Arnica chamissonis ssp. foliosa var. andina Chamisso arnica

Arnica cordifolia Heartleaf arnica

Arnica mollis Hairy arnica

Artemisia biennis Biennial wormwood

Artemisia biennis var. biennis Biennial wormwood

Artemisia bigelovii Bigelow sage

Artemisia campestris Field sagewort

Artemisia campestris ssp. borealis Field sagewort

Artemisia campestris ssp. borealis var. borealis Field sagewort

Artemisia campestris ssp. borealis var. 

scouleriana

Field sagewort

Artemisia campestris ssp. caudata Field sagewort

Artemisia cana Silver sagebrush

Artemisia cana ssp. cana Silver sagebrush

Artemisia carruthii Carruth’s sagewort

Artemisia dracunculus Tarragon

Artemisia franserioides Ragweed sagebrush

Artemisia frigida Prairie sagewort

Artemisia longifolia Longleaf wormwood

Artemisia ludoviciana White sagebrush

Artemisia ludoviciana ssp. albula White sagebrush

Artemisia ludoviciana ssp. incompta White sagebrush

Artemisia ludoviciana ssp. ludoviciana White sagebrush

Artemisia michauxiana Michaux’s wormwood

Artemisia parryi Parry’s wormwood

Artemisia scopulorum Alpine sagebrush

Artemisia tridentata Big sagebrush

Artemisia tridentata ssp. tridentata Basin big sagebrush

Artemisia tridentata ssp. vaseyana Mountain big sagebrush

Asclepias hallii Hall’s milkweed

Asclepias speciosa Showy milkweed

Asparagus officinalis Garden asparagus

Asplenium septentrionale Forked spleenwort

Aster alpinus Alpine aster

Aster alpinus var. vierhapperi Vierhapper’s aster

Astragalus agrestis Purple milkvetch

Astragalus allochrous Halfmoon milkvetch

Astragalus allochrous var. playanus Halfmoon milkvetch

Astragalus alpinus Alpine milkvetch
Appendix D—Species List for the San Luis Valley Conservation Area 105

Scientific name Common name Status

Astragalus alpinus var. alpinus Alpine milkvetch

Astragalus bisulcatus Twogrooved milkvetch

Astragalus bodinii Bodin’s milkvetch

Astragalus brandegeei Brandegee’s milkvetch

Astragalus ceramicus Painted milkvetch

Astragalus ceramicus var. ceramicus Painted milkvetch

Astragalus cerussatus Powdery milkvetch

Astragalus crassicarpus Groundplum milkvetch

Astragalus crassicarpus var. crassicarpus Groundplum milkvetch

Astragalus drummondii Drummond’s milkvetch

Astragalus flexuosus Flexile milkvetch

Astragalus flexuosus var. flexuosus Flexile milkvetch

Astragalus hallii Hall’s milkvetch

Astragalus hallii var. hallii Hall’s milkvetch

Astragalus kentrophyta Spiny milkvetch

Astragalus kentrophyta var. tegetarius Mat milkvetch

Astragalus laxmannii Laxmann’s milkvetch

Astragalus laxmannii var. robustior Prairie milkvetch

Astragalus miser Timber milkvetch

Astragalus miser var. oblongifolius Timber milkvetch

Astragalus pattersonii Patterson’s milkvetch

Astragalus ripleyi Ripley’s milkvetch

Astragalus scopulorum Rocky Mountain milkvetch

Astragalus tenellus Looseflower milkvetch

Atriplex × aptera Moundscale

Atriplex argentea Silverscale saltbush

Atriplex canescens Fourwing saltbush

Atriplex canescens var. canescens Fourwing saltbush

Atriplex patula Spear saltbush

Atriplex rosea Tumbling saltweed

Atriplex truncata Wedgescale saltbush

Atriplex wolfii Wolf’s saltweed

Bahia dissecta Ragleaf bahia

Balsamorhiza sagittata Arrowleaf balsamroot

Bassia hyssopifolia Fivehorn smotherweed

Bassia scoparia Burningbush

Beckmannia syzigachne American sloughgrass

Berberis fendleri Colorado barberry

Besseya alpina Alpine besseya

Besseya plantaginea White River coraldrops

Betula occidentalis Water birch

Bidens cernua Nodding beggartick

Bidens frondosa Devil’s beggartick

Bidens tenuisecta Slimlobe beggarticks

Bidens vulgata Big devils beggartick
106 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Blepharoneuron tricholepis Pine dropseed

Botrychium hesperium Western moonwort

Botrychium pinnatum Northern moonwort

Botrychium simplex Little grapefern

Bouteloua gracilis Blue grama

Bouteloua simplex Matted grama

Brassica juncea India mustard

Brassica napus Rape

Brickellia eupatorioides False boneset

Brickellia eupatorioides var. chlorolepis False boneset

Brickellia grandiflora Tasselflower brickellbush

Bromus ciliatus Fringed brome

Bromus ciliatus var. ciliatus Fringed brome

Bromus inermis Smooth brome

Bromus inermis ssp. inermis Smooth brome

Bromus inermis ssp. inermis var. inermis Smooth brome

Bromus lanatipes Woolly brome

Bromus porteri Porter brome

Bromus tectorum Cheatgrass

Calamagrostis canadensis Bluejoint

Calamagrostis purpurascens Purple reedgrass

Calamagrostis purpurascens var. purpurascens Purple reedgrass

Calamagrostis stricta Slimstem reedgrass

Callitriche palustris Vernal water-starwort

Calochortus gunnisonii Gunnison’s mariposa lily

Calochortus gunnisonii var. gunnisonii Gunnison’s mariposa lily

Caltha leptosepala White marsh marigold

Caltha leptosepala ssp. leptosepala White marsh marigold

Caltha leptosepala ssp. leptosepala var. 

leptosepala

White marsh marigold

Camelina microcarpa Littlepod false flax

Campanula parryi Parry’s bellflower

Campanula parryi var. parryi Parry’s bellflower

Campanula rotundifolia Bluebell bellflower

Campanula uniflora Arctic bellflower

Capsella bursa-pastoris Shepherd’s purse

Cardamine cordifolia Heartleaf bittercress

Cardamine cordifolia var. incana Heartleaf bittercress

Cardaria chalepensis Lenspod whitetop

Cardaria draba Whitetop

Cardaria pubescens Hairy whitetop

Carex albonigra Blackandwhite sedge

Carex aquatilis Water sedge

Carex aquatilis var. aquatilis Water sedge

Carex atherodes Wheat sedge

Carex aurea Golden sedge
Appendix D—Species List for the San Luis Valley Conservation Area 107

Scientific name Common name Status

Carex bella Southwestern showy sedge

Carex brunnescens Brownish sedge

Carex brunnescens ssp. sphaerostachya Brownish sedge

Carex canescens Silvery sedge

Carex canescens ssp. canescens Silvery sedge

Carex diandra Lesser panicled sedge

Carex disperma Softleaf sedge

Carex douglasii Douglas’ sedge

Carex duriuscula Needleleaf sedge

Carex ebenea Ebony sedge

Carex elynoides Blackroot sedge

Carex geophila White Mountain sedge

Carex geyeri Geyer’s sedge

Carex hallii Deer sedge

Carex haydeniana Cloud sedge

Carex heteroneura Different-nerve sedge

Carex heteroneura var. brevisquama Different-nerve sedge

Carex heteroneura var. chalciolepis Holm sedge

Carex inops Long-stolon sedge

Carex inops ssp. heliophila Sun sedge

Carex microptera Smallwing sedge

Carex nebrascensis Nebraska sedge

Carex nelsonii Nelson’s sedge

Carex nigricans Black alpine sedge

Carex norvegica Norway sedge

Carex norvegica ssp. stevenii Steven’s sedge

Carex nova Black sedge

Carex obtusata Obtuse sedge

Carex occidentalis Western sedge

Carex parryana Parry’s sedge

Carex parryana var. parryana Parry’s sedge

Carex pellita Woolly sedge

Carex perglobosa Globe sedge

Carex phaeocephala Dunhead sedge

Carex praegracilis Clustered field sedge

Carex praticola Meadow sedge

Carex pyrenaica Pyrenean sedge

Carex pyrenaica ssp. pyrenaica Pyrenean sedge

Carex scopulorum Mountain sedge

Carex siccata Dryspike sedge

Carex simulata Analogue sedge

Carex utriculata Northwest Territory sedge

Carex vernacula Native sedge

Carex vesicaria Blister sedge

Carex vesicaria var. vesicaria Blister sedge
108 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Carum carvi Caraway

Castilleja flava Yellow Indian paintbrush

Castilleja flava var. flava Yellow Indian paintbrush

Castilleja haydenii Hayden’s Indian paintbrush

Castilleja integra Wholeleaf Indian paintbrush

Castilleja integra var. integra Wholeleaf Indian paintbrush

Castilleja linariifolia Wyoming Indian paintbrush

Castilleja miniata Giant red Indian paintbrush

Castilleja miniata ssp. miniata Giant red Indian paintbrush

Castilleja occidentalis Western Indian paintbrush

Castilleja rhexiifolia Splitleaf Indian paintbrush

Castilleja sulphurea Sulphur Indian paintbrush

Ceanothus fendleri Fendler’s ceanothus

Ceanothus velutinus Snowbrush ceanothus

Ceanothus velutinus var. velutinus Snowbrush ceanothus

Cerastium arvense Field chickweed

Cerastium arvense ssp. strictum Feld chickweed

Cerastium beeringianum Bering chickweed

Cerastium beeringianum ssp. earlei Bering chickweed

Cercocarpus montanus Alderleaf mountain mahogany

Chaenactis douglasii Douglas’ dustymaiden

Chaenactis douglasii var. alpina Alpine dustymaiden

Chaetopappa ericoides Rose heath

Chamaerhodos erecta Little rose

Chamaerhodos erecta ssp. nuttallii Nuttall’s little rose

Chamaesyce serpyllifolia Thymeleaf sandmat

Chamaesyce serpyllifolia ssp. serpyllifolia Thymeleaf sandmat

Chamerion angustifolium Fireweed

Chamerion angustifolium ssp. circumvagum Fireweed

Cheilanthes feei Slender lipfern

Cheilanthes fendleri Fendler’s lipfern

Chenopodium album Lambsquarters

Chenopodium atrovirens Pinyon goosefoot

Chenopodium berlandieri Pitseed goosefoot

Chenopodium botrys Jerusalem oak goosefoot

Chenopodium desiccatum Aridland goosefoot

Chenopodium foliosum Leafy goosefoot

Chenopodium fremontii Fremont’s goosefoot

Chenopodium fremontii var. fremontii Fremont’s goosefoot

Chenopodium glaucum Oakleaf goosefoot

Chenopodium graveolens Fetid goosefoot

Chenopodium leptophyllum Narrowleaf goosefoot

Chenopodium pratericola Desert goosefoot

Chenopodium rubrum Red goosefoot

Chenopodium watsonii Watson’s goosefoot
Appendix D—Species List for the San Luis Valley Conservation Area 109

Scientific name Common name Status

Chionophila jamesii Rocky Mountain snowlover

Chrysothamnus greenei Greene’s rabbitbrush

Chrysothamnus vaseyi Vasey’s rabbitbrush

Chrysothamnus viscidiflorus Yellow rabbitbrush

Chrysothamnus viscidiflorus ssp. lanceolatus Yellow rabbitbrush

Cicuta maculata Spotted water hemlock

Cirsium arvense Canada thistle

Cirsium canescens Prairie thistle

Cirsium centaureae Fringed thistle

Cirsium ochrocentrum Yellowspine thistle

Cirsium ochrocentrum ssp. ochrocentrum Yellowspine thistle

Cirsium pallidum Pale thistle

Cirsium parryi Parry’s thistle

Cirsium parryi ssp. parryi Parry’s thistle

Cirsium scariosum Meadow thistle

Cirsium scopulorum Mountain thistle

Claytonia megarhiza Alpine springbeauty

Claytonia megarhiza var. megarhiza Alpine springbeauty

Clematis columbiana Rock clematis

Clematis columbiana var. columbiana Rock clematis

Clematis hirsutissima Hairy clematis

Clematis hirsutissima var. scottii Scott’s clematis

Clematis ligusticifolia Western white clematis

Clematis ligusticifolia var. ligusticifolia Western white clematis

Cleome multicaulis Slender spiderflower

Cleome serrulata Rocky Mountain beeplant

Collomia linearis Tiny trumpet

Comandra umbellata Bastard toadflax

Comandra umbellata ssp. pallida Pale bastard toadflax

Comarum palustre Purple marshlocks

Conioselinum scopulorum Rocky Mountain hemlockparsley

Convolvulus arvensis Field bindweed

Conyza canadensis Canadian horseweed

Corallorhiza maculata Summer coralroot

Corallorhiza striata Hooded coralroot

Corallorhiza trifida Yellow coralroot

Coreopsis tinctoria Golden tickseed

Coreopsis tinctoria var. tinctoria Golden tickseed

Corispermum americanum American bugseed

Corispermum americanum var. rydbergii American bugseed

Corispermum villosum Hairy bugseed

Cornus canadensis Bunchberry dogwood

Cornus sericea Redosier dogwood

Cornus sericea ssp. sericea Redosier dogwood

Corydalis aurea Scrambled eggs
110 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Corydalis caseana Sierra fumewort

Corydalis caseana ssp. brandegeei Brandegee’s fumewort

Corydalis curvisiliqua Curvepod fumewort

Corydalis curvisiliqua ssp. occidentalis Curvepod fumewort

Crataegus rivularis River hawthorn

Crepis occidentalis Largeflower hawksbeard

Crepis occidentalis ssp. occidentalis Largeflower hawksbeard

Crepis runcinata Fiddleleaf hawksbeard

Crepis runcinata ssp. runcinata Fiddleleaf hawksbeard

Cryptantha bakeri Baker’s cryptantha

Cryptantha cinerea James’ cryptantha

Cryptantha cinerea var. jamesii James’ cryptantha

Cryptantha cinerea var. pustulosa James’ cryptantha

Cryptantha fendleri Sanddune cryptantha

Cryptantha minima Little cryptantha

Cryptantha weberi Weber’s cryptantha

Cryptogramma acrostichoides American rockbrake

Cycloloma atriplicifolium Winged pigweed

Cymopterus acaulis Plains springparsley

Cymopterus montanus Mountain springparsley

Cynoglossum officinale Gypsyflower

Cyperus squarrosus Bearded flatsedge

Cystopteris fragilis Brittle bladderfern

Cystopteris reevesiana Reeves’ bladderfern

Dalea leporina Foxtail prairie clover

Danthonia californica California oatgrass

Danthonia intermedia Timber oatgrass

Danthonia parryi Parry’s oatgrass

Dasiphora fruticosa Shrubby cinquefoil

Dasiphora fruticosa ssp. floribunda Shrubby cinquefoil

Delphinium alpestre Colorado larkspur

Delphinium barbeyi Subalpine larkspur

Delphinium nuttallianum Twolobe larkspur

Delphinium ramosum Mountain larkspur

Delphinium robustum Wahatoya Creek larkspur

Deschampsia cespitosa Tufted hairgrass

Descurainia incana Mountain tansymustard

Descurainia incana ssp. incisa Mountain tansymustard

Descurainia incana ssp. viscosa Mountain tansymustard

Descurainia pinnata Western tansymustard

Descurainia pinnata ssp. filipes Western tansymustard

Descurainia ramosissima Villa Grove tansymustard

Distichlis spicata Saltgrass

Dodecatheon pulchellum Darkthroat shootingstar

Dodecatheon pulchellum ssp. pulchellum Darkthroat shootingstar
Appendix D—Species List for the San Luis Valley Conservation Area 111

Scientific name Common name Status

Draba aurea Golden draba

Draba crassa Thickleaf draba

Draba crassifolia Snowbed draba

Draba fladnizensis Austrian draba

Draba grayana Gray’s draba

Draba helleriana Heller’s draba

Draba helleriana var. helleriana Heller’s draba

Draba rectifructa Mountain draba

Draba smithii Smith’s draba

Draba spectabilis Showy draba

Draba streptobrachia Alpine tundra draba

Draba streptocarpa Pretty draba

Dracocephalum parviflorum American dragonhead

Dryas octopetala Eightpetal mountain-avens

Dryas octopetala ssp. hookeriana Hooker’s mountain-avens

Dryopteris filix-mas Male fern

Dyssodia papposa Fetid marigold

Echinocereus triglochidiatus Kingcup cactus

Echinocereus triglochidiatus var.

triglochidiatus

Kingcup cactus

Echinocereus viridiflorus Nylon hedgehog cactus

Echinocereus viridiflorus var. viridiflorus Nylon hedgehog cactus

Echinochloa crus-galli Barnyardgrass

Echinocystis lobata Wild cucumber

Elaeagnus commutata Silverberry

Eleocharis acicularis Needle spikerush

Eleocharis palustris Common spikerush

Eleocharis palustris var. palustris Common spikerush

Eleocharis quinqueflora Fewflower spikerush

× Elyhordeum macounii Macoun’s barley

Elymus canadensis Canada wildrye

Elymus elymoides Squirreltail

Elymus elymoides ssp. brevifolius Squirreltail

Elymus lanceolatus Thickspike wheatgrass

Elymus lanceolatus ssp. lanceolatus Thickspike wheatgrass

Elymus repens Quackgrass

Elymus scribneri Spreading wheatgrass

Elymus trachycaulus Slender wheatgrass

Elymus trachycaulus ssp. trachycaulus Slender wheatgrass

Epilobium brachycarpum Tall annual willowherb

Epilobium ciliatum Fringed willowherb

Epilobium ciliatum ssp. glandulosum Fringed willowherb

Epilobium halleanum Glandular willowherb

Epilobium hornemannii Hornemann’s willowherb

Epilobium hornemannii ssp. hornemannii Hornemann’s willowherb

Epilobium saximontanum Rocky Mountain willowherb
112 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Equisetum arvense Field horsetail

Equisetum hyemale Scouringrush horsetail

Equisetum hyemale var. affine Scouringrush horsetail

Equisetum laevigatum Smooth horsetail

Equisetum pratense Meadow horsetail

Equisetum variegatum Variegated scouringrush

Equisetum variegatum var. variegatum Variegated scouringrush

Eragrostis pilosa Indian lovegrass

Ericameria nauseosa Rubber rabbitbrush

Ericameria nauseosa ssp. consimilis Rubber rabbitbrush

Ericameria nauseosa ssp. consimilis var. 

oreophila

Rubber rabbitbrush

Ericameria nauseosa ssp. nauseosa Rubber rabbitbrush

Ericameria nauseosa ssp. nauseosa var. 

bigelovii

Rubber rabbitbrush

Ericameria nauseosa ssp. nauseosa var. 

glabrata

Rubber rabbitbrush

Ericameria nauseosa ssp. nauseosa var. 

nauseosa

Rubber rabbitbrush

Ericameria parryi Parry’s rabbitbrush

Ericameria parryi var. affinis Parry’s rabbitbrush

Ericameria parryi var. parryi Parry’s rabbitbrush

Erigeron acris Bitter fleabane

Erigeron acris ssp. debilis Bitter fleabane

Erigeron acris ssp. politus Bitter fleabane

Erigeron canus Hoary fleabane

Erigeron colomexicanus Running fleabane

Erigeron compositus Cutleaf daisy

Erigeron coulteri Large mountain fleabane

Erigeron divergens Spreading fleabane

Erigeron elatior Tall fleabane

Erigeron engelmannii Engelmann’s fleabane

Erigeron engelmannii var. engelmannii Engelmann’s fleabane

Erigeron eximius Sprucefir fleabane

Erigeron flagellaris Trailing fleabane

Erigeron formosissimus Beautiful fleabane

Erigeron glabellus Streamside fleabane

Erigeron leiomerus Rockslide yellow fleabane

Erigeron lonchophyllus Shortray fleabane

Erigeron melanocephalus Blackhead fleabane

Erigeron peregrinus Subalpine fleabane

Erigeron peregrinus ssp. callianthemus Subalpine fleabane

Erigeron peregrinus ssp. callianthemus var. 

callianthemus

Subalpine fleabane

Erigeron philadelphicus Philadelphia fleabane

Erigeron philadelphicus var. philadelphicus Philadelphia fleabane

Erigeron pinnatisectus Featherleaf fleabane
Appendix D—Species List for the San Luis Valley Conservation Area 113

Scientific name Common name Status

Erigeron pumilus Shaggy fleabane

Erigeron pumilus ssp. pumilus Shaggy fleabane

Erigeron simplex Onestem fleabane

Erigeron speciosus Aspen fleabane

Erigeron speciosus var. speciosus Aspen fleabane

Erigeron subtrinervis Threenerve fleabane

Erigeron subtrinervis var. subtrinervis Threenerve fleabane

Erigeron ursinus Bear River fleabane

Erigeron vetensis Early bluetop fleabane

Erigeron vreelandii Vreeland’s erigeron

Eriodictyon angustifolium Narrowleaf yerba santa

Eriogonum alatum Winged buckwheat

Eriogonum alatum var. alatum Winged buckwheat

Eriogonum cernuum Nodding buckwheat

Eriogonum cernuum var. cernuum Nodding buckwheat

Eriogonum coloradense Colorado buckwheat

Eriogonum effusum Spreading buckwheat

Eriogonum effusum var. effusum Spreading buckwheat

Eriogonum jamesii James’ buckwheat

Eriogonum jamesii var. flavescens James’ buckwheat

Eriogonum jamesii var. jamesii James’ buckwheat

Eriogonum jamesii var. xanthum James’ buckwheat

Eriogonum lachnogynum Woollycup buckwheat

Eriogonum microthecum Slender buckwheat

Eriogonum racemosum Redroot buckwheat

Eriogonum umbellatum Sulphur-flower buckwheat

Eriogonum umbellatum var. aureum Sulphur-flower buckwheat

Eriogonum umbellatum var. majus Sulphur-flower buckwheat

Eriogonum umbellatum var. umbellatum Sulphur-flower buckwheat

Eriophorum angustifolium Tall cottongrass

Eriophorum angustifolium ssp. angustifolium Tall cottongrass

Eritrichium nanum Arctic alpine forget-me-not

Erysimum capitatum Sanddune wallflower

Erysimum capitatum var. capitatum Sanddune wallflower

Erysimum cheiranthoides Wormseed wallflower

Erysimum inconspicuum Shy wallflower

Erysimum inconspicuum var. inconspicuum Shy wallflower

Escobaria vivipara Spinystar

Escobaria vivipara var. vivipara Spinystar

Euphorbia brachycera Horned spurge

Euthamia graminifolia Flat-top goldentop

Euthamia graminifolia var. graminifolia Flat-top goldentop

Euthamia occidentalis Western goldentop

Fallugia paradoxa Apache plume

Festuca arizonica Arizona fescue
114 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Festuca brachyphylla Alpine fescue

Festuca brachyphylla ssp. coloradensis Colorado fescue

Festuca earlei Earle’s fescue

Festuca idahoensis Idaho fescue

Festuca idahoensis ssp. idahoensis Idaho fescue

Festuca minutiflora Smallflower fescue

Festuca rubra Red fescue

Festuca saximontana Rocky Mountain fescue

Festuca sororia Ravine fescue

Festuca thurberi Thurber’s fescue

Fragaria vesca Woodland strawberry

Fragaria vesca ssp. bracteata Woodland strawberry

Fragaria virginiana Virginia strawberry

Fragaria virginiana ssp. glauca Virginia strawberry

Frasera speciosa Elkweed

Gaillardia aristata Blanketflower

Galium boreale Northern bedstraw

Galium trifidum Threepetal bedstraw

Galium trifidum ssp. subbiflorum Threepetal bedstraw

Gaura coccinea Scarlet beeblossom

Gayophytum diffusum Spreading groundsmoke

Gayophytum diffusum ssp. parviflorum Spreading groundsmoke

Gayophytum ramosissimum Pinyon groundsmoke

Gentiana affinis Pleated gentian

Gentiana algida Whitish gentian

Gentiana fremontii Moss gentian

Gentiana parryi Parry’s gentian

Gentiana prostrata Pygmy gentian

Gentianella amarella Autumn dwarf gentian

Gentianella amarella ssp. acuta Autumn dwarf gentian

Gentianella amarella ssp. heterosepala Autumn dwarf gentian

Gentianella tenella Dane’s dwarf gentian

Gentianella tenella ssp. tenella Dane’s dwarf gentian

Gentianopsis barbellata Perennial fringed gentian

Gentianopsis thermalis Rocky Mountain fringed gentian

Geranium caespitosum Pineywoods geranium

Geranium caespitosum var. caespitosum Pineywoods geranium

Geranium richardsonii Richardson’s geranium

Geum aleppicum Yellow avens

Geum macrophyllum Largeleaf avens

Geum macrophyllum var. perincisum Largeleaf avens

Geum rivale Purple avens

Geum rossii Ross’ avens

Geum rossii var. turbinatum Ross’ avens

Geum triflorum Old man’s whiskers
Appendix D—Species List for the San Luis Valley Conservation Area 115

Scientific name Common name Status

Geum triflorum var. triflorum Old man’s whiskers

Glaux maritima Sea milkwort

Glyceria grandis American mannagrass

Glyceria grandis var. grandis American mannagrass

Glyceria striata Fowl mannagrass

Glycyrrhiza lepidota American licorice

Gnaphalium uliginosum Marsh cudweed

Goodyera oblongifolia Western rattlesnake plantain

Goodyera repens Lesser rattlesnake plantain

Gratiola neglecta Clammy hedgehyssop

Grindelia decumbens Reclined gumweed

Grindelia decumbens var. decumbens Reclined gumweed

Grindelia nuda Curlytop gumweed

Grindelia nuda var. aphanactis Curlytop gumweed

Grindelia squarrosa Curlycup gumweed

Gutierrezia sarothrae Broom snakeweed

Gymnocarpium dryopteris Western oakfern

Hackelia floribunda Manyflower stickseed

Halogeton glomeratus Saltlover

Hedysarum occidentale Western sweetvetch

Helianthella parryi Parry’s dwarf-sunflower

Helianthella quinquenervis Fivenerve helianthella

Helianthus annuus Common sunflower

Helianthus nuttallii Nuttall’s sunflower

Helianthus petiolaris Prairie sunflower

Heliomeris multiflora Showy goldeneye

Heliotropium curassavicum Salt heliotrope

Heliotropium curassavicum var. obovatum Seaside heliotrope

Heracleum maximum Common cowparsnip

Hesperostipa comata Needle and thread

Hesperostipa comata ssp. comata Needle and thread

Hesperostipa neomexicana New Mexico feathergrass

Heterotheca fulcrata Rockyscree false goldenaster

Heterotheca pumila Alpine false goldenaster

Heterotheca villosa Hairy false goldenaster

Heterotheca villosa var. minor Hairy false goldenaster

Heterotheca villosa var. nana Hairy false goldenaster

Heterotheca villosa var. villosa Hairy false goldenaster

Heuchera parvifolia Littleleaf alumroot

Heuchera parvifolia var. parvifolia Littleleaf alumroot

Hieracium gracile Slender hawkweed

Hieracium gracile var. gracile Slender hawkweed

Hierochloe hirta Northern sweetgrass

Hierochloe hirta ssp. arctica Northern sweetgrass

Hoffmannseggia glauca Indian rushpea
116 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Holodiscus dumosus Rockspirea

Hordeum brachyantherum Meadow barley

Hordeum brachyantherum ssp. brachyantherum Meadow barley

Hordeum jubatum Foxtail barley

Hordeum jubatum ssp. jubatum Foxtail barley

Humulus lupulus Common hop

Humulus lupulus var. neomexicanus Common hop

Hydrophyllum fendleri Fendler’s waterleaf

Hydrophyllum fendleri var. fendleri Fendler’s waterleaf

Hymenopappus filifolius Fineleaf hymenopappus

Hymenopappus filifolius var. cinereus Fineleaf hymenopappus

Hymenopappus filifolius var. parvulus Fineleaf hymenopappus

Hymenopappus newberryi Newberry’s hymenopappus

Hymenoxys helenioides Intermountain rubberweed

Hymenoxys hoopesii Owl’s-claws

Hymenoxys richardsonii Pingue rubberweed

Hymenoxys richardsonii var. richardsonii Pingue rubberweed

Hyoscyamus niger Black henbane

Hypericum scouleri Scouler’s St. Johnswort

Hypericum scouleri ssp. nortoniae Norton’s St. Johnswort

Ipomopsis aggregata Scarlet gilia

Ipomopsis aggregata ssp. candida Scarlet gilia

Ipomopsis aggregata ssp. collina Scarlet gilia

Ipomopsis longiflora Flaxflowered ipomopsis

Ipomopsis longiflora ssp. longiflora Flaxflowered ipomopsis

Ipomopsis multiflora Manyflowered ipomopsis

Iris missouriensis Rocky Mountain iris

Iva axillaris Povertyweed

Ivesia gordonii Gordon’s ivesia

Jamesia americana Fivepetal cliffbush

Jamesia americana var. americana Fivepetal cliffbush

Juncus arcticus Arctic rush

Juncus arcticus ssp. littoralis Mountain rush

Juncus bufonius Toad rush

Juncus bufonius var. bufonius Toad rush

Juncus castaneus Chestnut rush

Juncus castaneus ssp. castaneus Chestnut rush

Juncus castaneus ssp. castaneus var. 

castaneus

Chestnut rush

Juncus drummondii Drummond’s rush

Juncus interior Inland rush

Juncus longistylis Longstyle rush

Juncus longistylis var. longistylis Longstyle rush

Juncus mertensianus Mertens’ rush

Juncus saximontanus Rocky Mountain rush

Juncus torreyi Torrey’s rush
Appendix D—Species List for the San Luis Valley Conservation Area 117

Scientific name Common name Status

Juniperus communis Common juniper

Juniperus communis var. depressa Common juniper

Juniperus scopulorum Rocky Mountain juniper

Kalmia microphylla Alpine laurel

Kobresia myosuroides Bellardi bog sedge

Koeleria macrantha Prairie Junegrass

Krascheninnikovia lanata Winterfat

Lactuca tatarica Blue lettuce

Lactuca tatarica var. pulchella Blue lettuce

Lappula occidentalis Flatspine stickseed

Lappula occidentalis var. occidentalis Flatspine stickseed

Lathyrus eucosmus Bush vetchling

Lathyrus lanszwertii Nevada pea

Lathyrus lanszwertii var. leucanthus Nevada pea

Lathyrus latifolius Perennial pea

Lemna minuta Least duckweed

Lemna turionifera Turion duckweed

Lepidium alyssoides Mesa pepperwort

Lepidium alyssoides var. alyssoides Mesa pepperwort

Lepidium densiflorum Common pepperweed

Lepidium latifolium Broadleaved pepperweed

Lepidium ramosissimum Manybranched pepperweed

Leptochloa fusca Malabar sprangletop

Leptochloa fusca ssp. fascicularis Bearded sprangletop

Leptosiphon nuttallii Nuttall’s linanthus

Leptosiphon nuttallii ssp. nuttallii Nuttall’s linanthus

Lesquerella montana Mountain bladderpod

Levisticum officinale Garden lovage

Lewisia pygmaea Alpine lewisia

Leymus ambiguus Colorado wildrye

Leymus cinereus Basin wildrye

Leymus triticoides Beardless wildrye

Liatris punctata Dotted blazing star

Ligusticum porteri Porter’s licorice-root

Ligusticum porteri var. porteri Porter’s licorice-root

Limosella aquatica Water mudwort

Linanthus pungens Granite prickly phlox

Linnaea borealis Twinflower

Linnaea borealis ssp. americana Twinflower

Linum australe Southern flax

Linum australe var. australe Southern flax

Linum lewisii Lewis flax

Linum lewisii var. lewisii Prairie flax

Listera cordata Heartleaf twayblade

Listera cordata var. nephrophylla Heartleaf twayblade
118 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Lithophragma tenellum Slender woodland-star

Lithospermum incisum Narrowleaf stoneseed

Lithospermum multiflorum Manyflowered stoneseed

Lloydia serotina Common alplily

Lloydia serotina var. serotina Common alplily

Lonicera involucrata Twinberry honeysuckle

Lonicera involucrata var. involucrata Twinberry honeysuckle

Lupinus argenteus Silvery lupine

Lupinus bakeri Baker’s lupine

Lupinus bakeri ssp. bakeri Baker’s lupine

Lupinus caespitosus Stemless dwarf lupine

Lupinus caespitosus var. caespitosus Stemless dwarf lupine

Lupinus caudatus Tailcup lupine

Lupinus kingii King’s lupine

Lupinus pusillus Rusty lupine

Lupinus pusillus ssp. pusillus Rusty lupine

Lupinus sericeus Silky lupine

Lupinus sericeus ssp. sericeus Silky lupine

Luzula parviflora Smallflowered woodrush

Luzula spicata Spiked woodrush

Lycopus asper Rough bugleweed

Lygodesmia juncea Rush skeletonplant

Machaeranthera bigelovii Bigelow’s tansyaster

Machaeranthera bigelovii var. bigelovii Bigelow’s tansyaster

Machaeranthera canescens Hoary tansyaster

Machaeranthera canescens ssp. glabra Hoary tansyaster

Machaeranthera canescens ssp. glabra var. 

glabra

Hoary tansyaster

Machaeranthera coloradoensis Colorado tansyaster

Machaeranthera coloradoensis var. 

coloradoensis

Colorado tansyaster

Machaeranthera parviflora Smallflower tansyaster

Machaeranthera pinnatifida Lacy tansyaster

Machaeranthera pinnatifida ssp. pinnatifida Lacy tansyaster

Machaeranthera pinnatifida ssp. pinnatifida 

var. pinnatifida

Lacy tansyaster

Machaeranthera tanacetifolia Tanseyleaf tansyaster

Mahonia repens Creeping barberry

Maianthemum racemosum Feathery false lily of the valley

Maianthemum racemosum ssp. amplexicaule Feathery false lily of the valley

Maianthemum stellatum Starry false lily of the valley

Malva neglecta Common mallow

Marsilea vestita Hairy waterclover

Medicago sativa Alfalfa

Medicago sativa ssp. sativa Alfalfa

Melilotus officinalis Sweetclover
Appendix D—Species List for the San Luis Valley Conservation Area 119

Scientific name Common name Status

Mentha arvensis Wild mint

Mentzelia albicaulis Whitestem blazingstar

Mentzelia multiflora Adonis blazingstar

Mentzelia multiflora var. multiflora Adonis blazingstar

Mentzelia nuda Bractless blazingstar

Mentzelia rusbyi Rusby’s blazingstar

Mentzelia speciosa Jeweled blazingstar

Menyanthes trifoliata Buckbean

Mertensia alpina Alpine bluebells

Mertensia brevistyla Shortstyle bluebells

Mertensia ciliata Tall fringed bluebells

Mertensia ciliata var. ciliata Tall fringed bluebells

Mertensia franciscana Franciscan bluebells

Mertensia lanceolata Prairie bluebells

Mertensia lanceolata var. lanceolata Prairie bluebells

Mertensia oblongifolia Oblongleaf bluebells

Mimulus floribundus Manyflowered monkeyflower

Mimulus glabratus Roundleaf monkeyflower

Mimulus guttatus Seep monkeyflower

Minuartia obtusiloba Twinflower sandwort

Minuartia rubella Beautiful sandwort

Mirabilis linearis Narrowleaf four o’clock

Mirabilis multiflora Colorado four o’clock

Mirabilis oxybaphoides Smooth spreading four o’clock

Mitella pentandra Fivestamen miterwort

Mitella stauropetala Smallflower miterwort

Mitella stauropetala var. stenopetala Drywoods miterwort

Moehringia lateriflora Bluntleaf sandwort

Moehringia macrophylla Largeleaf sandwort

Monarda fistulosa Wild bergamot

Monarda fistulosa ssp. fistulosa Wild bergamot

Monarda fistulosa ssp. fistulosa var. 

menthifolia

Mintleaf bergamot

Monarda pectinata Pony beebalm

Moneses uniflora Single delight

Monolepis nuttalliana Nuttall’s povertyweed

Monotropa hypopithys Pinesap

Montia chamissoi Water minerslettuce

Muhlenbergia andina Foxtail muhly

Muhlenbergia asperifolia Scratchgrass

Muhlenbergia brevis Short muhly

Muhlenbergia filiculmis Slimstem muhly

Muhlenbergia filiformis Pullup muhly

Muhlenbergia minutissima Annual muhly

Muhlenbergia montana Mountain muhly

Muhlenbergia pungens Sandhill muhly
120 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Muhlenbergia richardsonis Mat muhly

Muhlenbergia torreyi Ring muhly

Munroa squarrosa False buffalograss

Myriophyllum sibiricum Shortspike watermilfoil

Nassella viridula Green needlegrass

Nasturtium officinale Watercress

Neoparrya lithophila Bill’s neoparrya

Noccaea montana Alpine pennycress

Noccaea montana var. montana Alpine pennycress

Nuphar lutea Yellow pond-lily

Nuphar lutea ssp. polysepala Rocky Mountain pond-lily

Oenothera albicaulis Whitest evening primrose

Oenothera caespitosa Tufted evening primrose

Oenothera caespitosa ssp. caespitosa Tufted evening primrose

Oenothera coronopifolia Crownleaf evening primrose

Oenothera elata Hooker’s evening primrose

Oenothera elata ssp. hirsutissima Hooker’s evening primrose

Oenothera flava Yellow evening primrose

Oenothera flava ssp. flava Yellow evening primrose

Oenothera pallida Pale evening primrose

Oenothera pallida ssp. runcinata Pale evening primrose

Oenothera villosa Hairy evening primrose

Oenothera villosa ssp. strigosa Hairy evening primrose

Opuntia polyacantha Plains pricklypear

Opuntia polyacantha var. polyacantha Hairspine pricklypear

Oreochrysum parryi Parry’s goldenrod

Oreoxis alpina Alpine oreoxis

Oreoxis alpina ssp. alpina Alpine oreoxis

Oreoxis alpina ssp. puberulenta Alpine oreoxis

Oreoxis bakeri Baker’s alpineparsley

Orobanche fasciculata Clustered broomrape

Orthilia secunda Sidebells wintergreen

Orthocarpus luteus Yellow owl’s-clover

Oryzopsis asperifolia Roughleaf ricegrass

Osmorhiza depauperata Bluntseed sweetroot

Oxypolis fendleri Fendler’s cowbane

Oxyria digyna Alpine mountainsorrel

Oxytropis campestris Field locoweed

Oxytropis deflexa Nodding locoweed

Oxytropis deflexa var. sericea Blue nodding locoweed

Oxytropis lambertii Purple locoweed

Oxytropis lambertii var. lambertii Purple locoweed

Oxytropis parryi Parry’s oxytrope

Oxytropis sericea White locoweed

Oxytropis sericea var. sericea White locoweed
Appendix D—Species List for the San Luis Valley Conservation Area 121

Scientific name Common name Status

Oxytropis splendens Showy locoweed

Packera cana Woolly groundsel

Packera crocata Saffron ragwort

Packera dimorphophylla Splitleaf groundsel

Packera dimorphophylla var. intermedia Splitleaf groundsel

Packera fendleri Fendler’s ragwort

Packera neomexicana New Mexico groundsel

Packera neomexicana var. mutabilis New Mexico groundsel

Packera pseudaurea Falsegold groundsel

Packera pseudaurea var. pseudaurea Falsegold groundsel

Packera streptanthifolia Rocky Mountain groundsel

Packera tridenticulata Threetooth ragwort

Packera werneriifolia Hoary groundsel

Parietaria pensylvanica Pennsylvania pellitory

Parnassia palustris Marsh grass of Parnassus

Parnassia palustris var. montanensis Mountain grass of Parnassus

Paronychia pulvinata Rocky Mountain nailwort

Paronychia sessiliflora Creeping nailwort

Parthenium tetraneuris Arkansas River feverfew

Pascopyrum smithii Western wheatgrass

Pastinaca sativa Wild parsnip

Paxistima myrsinites Oregon boxleaf

Pectis angustifolia Lemonscent

Pectis angustifolia var. angustifolia Narrowleaf pectis

Pedicularis canadensis Canadian lousewort

Pedicularis canadensis ssp. fluviatilis Canadian lousewort

Pedicularis crenulata Meadow lousewort

Pedicularis groenlandica Elephanthead lousewort

Pedicularis parryi Parry’s lousewort

Pedicularis parryi ssp. parryi Parry’s lousewort

Pedicularis procera Giant lousewort

Pedicularis racemosa Sickletop lousewort

Pedicularis racemosa ssp. alba Sickletop lousewort

Pediocactus simpsonii Mountain ball cactus

Penstemon barbatus Beardlip penstemon

Penstemon caespitosus Mat penstemon

Penstemon griffinii Griffin’s beardtongue

Penstemon hallii Hall’s beardtongue

Penstemon procerus Littleflower penstemon

Penstemon procerus var. procerus Pincushion beardtongue

Penstemon rydbergii Rydberg’s penstemon

Penstemon secundiflorus Sidebells penstemon

Penstemon strictus Rocky Mountain penstemon

Penstemon unilateralis Oneside penstemon

Penstemon whippleanus Whipple’s penstemon
122 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Pericome caudata Mountain tail-leaf

Petasites frigidus Arctic sweet coltsfoot

Petasites frigidus var. sagittatus Arrowleaf sweet coltsfoot

Phacelia alba White phacelia

Phacelia bakeri Baker’s phacelia

Phacelia glandulosa Glandular phacelia

Phacelia glandulosa var. glandulosa Glandular phacelia

Phacelia heterophylla Varileaf phacelia

Phacelia heterophylla ssp. heterophylla Varileaf phacelia

Phacelia sericea Silky phacelia

Phacelia sericea ssp. sericea Silky phacelia

Phalaris arundinacea Reed canarygrass

Phleum alpinum Alpine timothy

Phleum pratense Timothy

Phlox austromontana Mountain phlox

Phlox condensata Dwarf phlox

Phlox hoodii Spiny phlox

Phlox pulvinata Cushion phlox

Physaria floribunda Oointtip twinpod

Physocarpus monogynus Mountain ninebark

Picea engelmannii Engelmann spruce

Picea engelmannii var. engelmannii Engelmann spruce

Picea pungens Blue spruce

Picradeniopsis oppositifolia Oppositeleaf bahia

Pinus aristata Bristlecone pine

Pinus edulis Twoneedle pinyon

Pinus flexilis Limber pine

Pinus ponderosa Ponderosa pine

Pinus ponderosa var. brachyptera Ponderosa pine

Pinus ponderosa var. scopulorum Ponderosa pine

Pinus strobiformis Southwestern white pine

Piptatherum micranthum Littleseed ricegrass

Piptatherum pungens Mountain ricegrass

Plagiobothrys scouleri Scouler’s popcornflower

Plagiobothrys scouleri var. hispidulus Sleeping popcornflower

Plantago eriopoda Redwool plantain

Plantago major Common plantain

Platanthera dilatata Scentbottle

Platanthera dilatata var. albiflora Scentbottle

Platanthera obtusata Bluntleaved orchid

Platanthera obtusata ssp. obtusata Bluntleaved orchid

Platanthera sparsiflora Sparse-flowered bog orchid

Platanthera sparsiflora var. ensifolia Sparse-flowered bog orchid

Poa alpina Alpine bluegrass

Poa annua Annual bluegrass
Appendix D—Species List for the San Luis Valley Conservation Area 123

Scientific name Common name Status

Poa arctica Arctic bluegrass

Poa arctica ssp. aperta Arctic bluegrass

Poa compressa Canada bluegrass

Poa fendleriana Muttongrass

Poa glauca Glaucous bluegrass

Poa glauca ssp. rupicola Timberline bluegrass

Poa leptocoma Marsh bluegrass

Poa lettermanii Letterman’s bluegrass

Poa nemoralis Wood bluegrass

Poa nemoralis ssp. interior Inland bluegrass

Poa palustris Fowl bluegrass

Poa pratensis Kentucky bluegrass

Poa pratensis ssp. pratensis Kentucky bluegrass

Poa reflexa Nodding bluegrass

Poa secunda Sandberg bluegrass

Podistera eastwoodiae Eastwood’s podistera

Polemonium brandegeei Brandegee’s Jacob’s-ladder

Polemonium confertum Rocky Mountain Jacob’s-ladder

Polemonium foliosissimum Towering Jacob’s-ladder

Polemonium occidentale Western polemonium

Polemonium occidentale ssp. occidentale Western polemonium

Polemonium pulcherrimum Jacob’s-ladder

Polemonium pulcherrimum ssp. delicatum Jacob’s-ladder

Polemonium viscosum Sticky polemonium

Polygonum amphibium Water knotweed

Polygonum amphibium var. emersum Longroot smartweed

Polygonum arenastrum Oval-leaf knotweed

Polygonum argyrocoleon Silversheath knotweed

Polygonum bistortoides American bistort

Polygonum douglasii Douglas’ knotweed

Polygonum pensylvanicum Pennsylvania smartweed

Polygonum persicaria Spotted ladysthumb

Polygonum viviparum Alpine bistort

Populus × acuminata Lanceleaf cottonwood

Populus angustifolia Narrowleaf cottonwood

Populus tremuloides Quaking aspen

Portulaca oleracea Little hogweed

Potamogeton alpinus Alpine pondweed

Potamogeton foliosus Leafy pondweed

Potamogeton foliosus ssp. foliosus Leafy pondweed

Potamogeton nodosus Longleaf pondweed

Potamogeton pusillus Small pondweed

Potamogeton pusillus ssp. pusillus Small pondweed

Potentilla ambigens Silkyleaf cinquefoil

Potentilla concinna Elegant cinquefoil
124 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Potentilla concinna var. concinna Elegant cinquefoil

Potentilla diversifolia Varileaf cinquefoil

Potentilla diversifolia var. diversifolia Varileaf cinquefoil

Potentilla gracilis Slender cinquefoil

Potentilla hippiana Woolly cinquefoil

Potentilla hippiana var. hippiana Woolly cinquefoil

Potentilla norvegica Norwegian cinquefoil

Potentilla norvegica ssp. monspeliensis Norwegian cinquefoil

Potentilla paradoxa Paradox cinquefoil

Potentilla pensylvanica Pennsylvania cinquefoil

Potentilla pensylvanica var. pensylvanica Pennsylvania cinquefoil

Potentilla plattensis Platte River cinquefoil

Potentilla pulcherrima Beautiful cinquefoil

Potentilla rivalis Brook cinquefoil

Potentilla subjuga Colorado cinquefoil

Potentilla uniflora Oneflower cinquefoil

Primula angustifolia Alpine primrose

Primula parryi Parry’s primrose

Prunella vulgaris Common selfheal

Prunella vulgaris ssp. lanceolata Lance selfheal

Prunus pensylvanica Pin cherry

Prunus pensylvanica var. pensylvanica Pin cherry

Prunus virginiana Chokecherry

Prunus virginiana var. melanocarpa Black chokecherry

Psathyrostachys juncea Russian wildrye

Pseudocymopterus montanus Alpine false springparsley

Pseudotsuga menziesii Douglas-fir

Pseudotsuga menziesii var. glauca Rocky Mountain Douglas-fir

Psoralidium lanceolatum Lemon scurfpea

Pteridium aquilinum Western brackenfern

Pteridium aquilinum var. pubescens Hairy brackenfern

Pterospora andromedea Woodland pinedrops

Pteryxia hendersonii Henderson’s wavewing

Puccinellia nuttalliana Nuttall’s alkaligrass

Pulsatilla patens Eastern pasqueflower

Pulsatilla patens ssp. multifida Cutleaf anemone

Pyrola asarifolia Liverleaf wintergreen

Pyrola asarifolia ssp. asarifolia Liverleaf wintergreen

Pyrola chlorantha Greenflowered wintergreen

Pyrola minor Snowline wintergreen

Pyrrocoma clementis Tranquil goldenweed

Pyrrocoma clementis var. clementis Tranquil goldenweed

Pyrrocoma lanceolata Lanceleaf goldenweed

Pyrrocoma lanceolata var. lanceolata Lanceleaf goldenweed

Pyrrocoma uniflora Plantain goldenweed
Appendix D—Species List for the San Luis Valley Conservation Area 125

Scientific name Common name Status

Pyrrocoma uniflora var. uniflora Plantain goldenweed

Quercus gambelii Gambel oak

Quercus gambelii var. gambelii Gambel oak

Ranunculus abortivus Littleleaf buttercup

Ranunculus alismifolius Plantainleaf buttercup

Ranunculus alismifolius var. montanus Waterplantain buttercup

Ranunculus cardiophyllus Heartleaf buttercup

Ranunculus cymbalaria Alkali buttercup

Ranunculus gmelinii Gmelin’s buttercup

Ranunculus hyperboreus High northern buttercup

Ranunculus inamoenus Graceful buttercup

Ranunculus macauleyi Rocky Mountain buttercup

Ranunculus macounii Macoun’s buttercup

Ranunculus sceleratus Cursed buttercup

Ranunculus sceleratus var. multifidus Cursed buttercup

Ranunculus sceleratus var. sceleratus Cursed buttercup

Ranunculus trichophyllus Threadleaf crowfoot

Ranunculus trichophyllus var. trichophyllus Threadleaf crowfoot

Ranunculus uncinatus Woodland buttercup

Redfieldia flexuosa Blowout grass

Rhinanthus minor Little yellow rattle

Rhinanthus minor ssp. minor Little yellow rattle

Rhodiola integrifolia Ledge stonecrop

Rhodiola rhodantha Redpod stonecrop

Rhus trilobata Skunkbush sumac

Rhus trilobata var. trilobata Skunkbush sumac

Ribes aureum Golden currant

Ribes cereum Wax currant

Ribes cereum var. pedicellare Whisky currant

Ribes inerme Whitestem gooseberry

Ribes inerme var. inerme Whitestem gooseberry

Ribes laxiflorum Trailing black currant

Ribes leptanthum Trumpet gooseberry

Ribes montigenum Gooseberry currant

Ribes wolfii Wolf’s currant

Rorippa alpina Alpine yellowcress

Rorippa curvipes Bluntleaf yellowcress

Rorippa curvipes var. curvipes Bluntleaf yellowcress

Rorippa curvipes var. truncata Bluntleaf yellowcress

Rorippa palustris Bog yellowcress

Rorippa palustris ssp. hispida Hispid yellowcress

Rorippa sinuata Spreading yellowcress

Rorippa sphaerocarpa Roundfruit yellowcress

Rosa acicularis Prickly rose

Rosa acicularis ssp. sayi Prickly rose
126 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Rosa woodsii Woods’ rose

Rosa woodsii var. ultramontana Woods’ rose

Rubus deliciosus Delicious raspberry

Rubus idaeus American red raspberry

Rubus idaeus ssp. strigosus Grayleaf red raspberry

Rubus parviflorus Thimbleberry

Rubus parviflorus var. parviflorus Thimbleberry

Rudbeckia hirta Blackeyed Susan

Rudbeckia hirta var. pulcherrima Blackeyed Susan

Rudbeckia laciniata Cutleaf coneflower

Rudbeckia laciniata var. ampla Cutleaf coneflower

Rumex aquaticus Western dock

Rumex aquaticus var. fenestratus Western dock

Rumex densiflorus Denseflowered dock

Rumex maritimus Golden dock

Rumex salicifolius Willow dock

Rumex salicifolius var. mexicanus Mexican dock

Rumex venosus Veiny dock

Sagina saginoides Arctic pearlwort

Sagittaria cuneata Arumleaf arrowhead

Salix amygdaloides Peachleaf willow

Salix bebbiana Bebb willow

Salix brachycarpa Shortfruit willow

Salix brachycarpa var. brachycarpa Shortfruit willow

Salix drummondiana Drummond’s willow

Salix exigua Narrowleaf willow

Salix geyeriana Geyer willow

Salix ligulifolia Strapleaf willow

Salix lucida Shining willow

Salix lucida ssp. caudata Greenleaf willow

Salix monticola Park willow

Salix nivalis Snow willow

Salix orestera Sierra willow

Salix petrophila Alpine willow

Salix planifolia Diamondleaf willow

Salix planifolia ssp. planifolia Diamondleaf willow

Salix scouleriana Scouler’s willow

Salix wolfii Wolf’s willow

Salsola tragus Prickly Russian thistle

Salvia reflexa Lanceleaf sage

Sambucus racemosa Red elderberry

Sambucus racemosa var. racemosa Red elderberry

Sarcobatus vermiculatus Greasewood

Saxifraga bronchialis Yellowdot saxifrage

Saxifraga bronchialis ssp. austromontana Matted saxifrage
Appendix D—Species List for the San Luis Valley Conservation Area 127

Scientific name Common name Status

Saxifraga caespitosa Tufted alpine saxifrage

Saxifraga caespitosa ssp. delicatula Tufted alpine saxifrage

Saxifraga cernua Nodding saxifrage

Saxifraga chrysantha Goldbloom saxifrage

Saxifraga flagellaris Whiplash saxifrage

Saxifraga flagellaris ssp. crandallii Crandall’s saxifrage

Saxifraga odontoloma Brook saxifrage

Saxifraga rhomboidea Diamondleaf saxifrage

Saxifraga rivularis Weak saxifrage

Schedonnardus paniculatus Tumblegrass

Schizachyrium scoparium Little bluestem

Schizachyrium scoparium var. scoparium Little bluestem

Schkuhria multiflora Manyflower false threadleaf

Schoenocrambe linearifolia Slimleaf plainsmustard

Schoenoplectus acutus Hardstem bulrush

Schoenoplectus acutus var. acutus Hardstem bulrush

Schoenoplectus maritimus Cosmopolitan bulrush

Schoenoplectus pungens Common threesquare

Schoenoplectus pungens var. longispicatus Common threesquare

Schoenoplectus tabernaemontani Softstem bulrush

Scirpus microcarpus Panicled bulrush

Scirpus nevadensis Nevada bulrush

Scrophularia lanceolata Lanceleaf figwort

Scutellaria galericulata Marsh skullcap

Sedum lanceolatum Spearleaf stonecrop

Sedum lanceolatum ssp. lanceolatum Spearleaf stonecrop

Selaginella densa Lesser spikemoss

Selaginella weatherbiana Weatherby’s spikemoss

Senecio amplectens Showy alpine ragwort

Senecio amplectens var. amplectens Showy alpine ragwort

Senecio amplectens var. holmii Holm’s ragwort

Senecio atratus Tall blacktip ragwort

Senecio bigelovii Nodding ragwort

Senecio bigelovii var. hallii Hall’s ragwort

Senecio crassulus Thickleaf ragwort

Senecio eremophilus Desert ragwort

Senecio eremophilus var. kingii King’s ragwort

Senecio fremontii Dwarf mountain ragwort

Senecio fremontii var. blitoides Dwarf mountain ragwort

Senecio pudicus Bashful ragwort

Senecio soldanella Colorado ragwort

Senecio spartioides Broom-like ragwort

Senecio spartioides var. multicapitatus Broom-like ragwort

Senecio taraxacoides Dandelion ragwort

Senecio triangularis Arrowleaf ragwort
128 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Senecio wootonii Wooton’s ragwort

Sesuvium verrucosum Verrucose seapurslane

Setaria viridis Green bristlegrass

Setaria viridis var. viridis Green bristlegrass

Shepherdia canadensis Russet buffaloberry

Sibbaldia procumbens Creeping sibbaldia

Sidalcea candida White checkerbloom

Sidalcea neomexicana Salt spring checkerbloom

Sidalcea neomexicana ssp. neomexicana Salt spring checkerbloom

Silene acaulis Moss campion

Silene acaulis var. subacaulescens Moss campion

Silene drummondii Drummond’s campion

Silene drummondii var. drummondii Drummond’s campion

Silene menziesii Menzies’ campion

Silene menziesii ssp. menziesii Menzies’ campion

Silene menziesii ssp. menziesii var. menziesii Menzies’ campion

Silene scouleri Simple campion

Silene scouleri ssp. hallii Simple campion

Sisymbrium altissimum Tall tumblemustard

Sisyrinchium demissum Stiff blue-eyed grass

Sisyrinchium montanum Strict blue-eyed grass

Sisyrinchium montanum var. montanum Strict blue-eyed grass

Sisyrinchium pallidum Pale blue-eyed grass

Sium suave Hemlock waterparsnip

Smelowskia calycina Alpine smelowskia

Smelowskia calycina var. americana American false candytuft

Solanum triflorum Cutleaf nightshade

Solidago canadensis Canada goldenrod

Solidago missouriensis Missouri goldenrod

Solidago multiradiata Rocky Mountain goldenrod

Solidago multiradiata var. scopulorum Manyray goldenrod

Solidago simplex Mt. Albert goldenrod

Solidago simplex ssp. simplex Mt. Albert goldenrod

Solidago simplex ssp. simplex var. simplex Mt. Albert goldenrod

Solidago velutina Threenerve goldenrod

Sonchus arvensis Field sowthistle

Sonchus arvensis ssp. uliginosus Moist sowthistle

Sophora nuttalliana Silky sophora

Spartina gracilis Alkali cordgrass

Sphaeralcea coccinea Scarlet globemallow

Sphaeralcea coccinea ssp. coccinea Scarlet globemallow

Sphaerophysa salsula Alkali swainsonpea

Sphenopholis obtusata Prairie wedgescale

Spiranthes romanzoffiana Hooded lady’s tresses

Sporobolus airoides Alkali sacaton
Appendix D—Species List for the San Luis Valley Conservation Area 129

Scientific name Common name Status

Sporobolus contractus Spike dropseed

Sporobolus cryptandrus Sand dropseed

Stachys pilosa Hairy hedgenettle

Stachys pilosa var. pilosa Hairy hedgenettle

Stellaria calycantha Northern starwort

Stellaria crassifolia Fleshy starwort

Stellaria crassifolia var. crassifolia Fleshy starwort

Stellaria longifolia Longleaf starwort

Stellaria longifolia var. longifolia Longleaf starwort

Stellaria longipes Longstalk starwort

Stellaria longipes ssp. longipes Chickweed, starwort

Stellaria umbellata Umbrella starwort

Stephanomeria pauciflora Brownplume wirelettuce

Streptopus amplexifolius Claspleaf twistedstalk

Streptopus amplexifolius var. chalazatus Tubercle twistedstalk

Suaeda calceoliformis Pursh seepweed

Suaeda moquinii Mojave seablite

Swertia perennis Felwort

Symphoricarpos occidentalis Western snowberry

Symphoricarpos rotundifolius Roundleaf snowberry

Symphoricarpos rotundifolius var. 

rotundifolius

Roundleaf snowberry

Symphyotrichum ascendens Western aster

Symphyotrichum boreale Northern bog aster

Symphyotrichum eatonii Eaton’s aster

Symphyotrichum ericoides White heath aster

Symphyotrichum ericoides var. ericoides White heath aster

Symphyotrichum falcatum White prairie aster

Symphyotrichum falcatum var. falcatum White prairie aster

Symphyotrichum foliaceum Alpine leafybract aster

Symphyotrichum frondosum Short-rayed alkali aster

Symphyotrichum lanceolatum White panicle aster

Symphyotrichum lanceolatum ssp. hesperium White panicle aster

Symphyotrichum lanceolatum ssp.

hesperium var. hesperium

White panicle aster

Symphyotrichum spathulatum Western mountain aster

Symphyotrichum spathulatum var. 

spathulatum

Western mountain aster

Taraxacum lyratum Harp dandelion

Taraxacum officinale Common dandelion

Taraxacum officinale ssp. ceratophorum Common dandelion

Tetradymia canescens Spineless horsebrush

Tetraneuris acaulis Stemless four-nerve daisy

Tetraneuris acaulis var. acaulis Stemless four-nerve daisy

Tetraneuris acaulis var. caespitosa Caespitose four-nerve daisy

Tetraneuris brandegeei Brandegee’s four-nerve daisy
130 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico

Scientific name Common name Status

Tetraneuris grandiflora Graylocks four-nerve daisy

Teucrium canadense Canada germander

Teucrium canadense var. occidentale Western germander

Thalictrum alpinum Alpine meadow-rue

Thalictrum fendleri Fendler’s meadow-rue

Thalictrum fendleri var. fendleri Fendler’s meadow-rue

Thalictrum sparsiflorum Fewflower meadow-rue

Thalictrum sparsiflorum var. saximontanum Fewflower meadow-rue

Thelesperma filifolium Stiff greenthread

Thelesperma filifolium var. intermedium Stiff greenthread

Thelesperma subnudum Navajo tea

Thelesperma subnudum var. subnudum Navajo tea

Thermopsis divaricarpa Spreadfruit goldenbanner

Thermopsis montana Mountain goldenbanner

Thermopsis montana var. montana Mountain goldenbanner

Thermopsis rhombifolia Prairie thermopsis

Thlaspi arvense Field pennycress

Tonestus pygmaeus Pygmy goldenweed

Townsendia eximia Tall Townsend daisy

Townsendia exscapa Stemless Townsend daisy

Townsendia grandiflora Largeflower Townsend daisy

Townsendia hookeri Hooker’s Townsend daisy

Townsendia leptotes Common Townsend daisy

Tragopogon porrifolius Salsify

Trautvetteria caroliniensis Carolina bugbane

Trautvetteria caroliniensis var. occidentalis Western bugbane

Trifolium attenuatum Rocky Mountain clover

Trifolium brandegeei Brandegee’s clover

Trifolium dasyphyllum Alpine clover

Trifolium dasyphyllum ssp. dasyphyllum Alpine clover

Trifolium hybridum Alsike clover

Trifolium longipes Longstalk clover

Trifolium longipes ssp. pygmaeum Pygmy clover

Trifolium nanum Dwarf clover

Trifolium parryi Parry’s clover

Trifolium parryi ssp. salictorum Parry’s clover

Trifolium repens White clover

Trifolium wormskioldii Cows clover

Triglochin maritima Seaside arrowgrass

Triglochin palustris Marsh arrowgrass

Tripterocalyx micranthus Smallflower sandverbena

Trisetum spicatum Spike trisetum

Trollius laxus American globeflower

Trollius laxus ssp. albiflorus American globeflower

Typha latifolia Broadleaf cattail
Appendix D—Species List for the San Luis Valley Conservation Area 131

Scientific name Common name Status

Urtica dioica Stinging nettle

Urtica dioica ssp. gracilis California nettle

Utricularia ochroleuca Yellowishwhite bladderwort

Vaccinium cespitosum Dwarf bilberry

Vaccinium myrtillus Whortleberry

Vaccinium scoparium Grouse whortleberry

Valeriana acutiloba Sharpleaf valerian

Valeriana acutiloba var. acutiloba Sharpleaf valerian

Valeriana arizonica Arizona valerian

Valeriana edulis Tobacco root

Valeriana edulis var. edulis Tobacco root

Veratrum tenuipetalum Colorado false hellebore

Verbena bracteata Bigbract verbena

Verbena macdougalii MacDougal verbena

Verbesina encelioides Golden crownbeard

Verbesina encelioides ssp. encelioides Golden crownbeard

Verbesina encelioides ssp. exauriculata Golden crownbeard

Veronica americana American speedwell

Veronica peregrina Neckweed

Veronica peregrina ssp. xalapensis Hairy purslane speedwell

Veronica serpyllifolia Thymeleaf speedwell

Veronica serpyllifolia ssp. humifusa Brightblue speedwell

Veronica wormskjoldii American alpine speedwell

Veronica wormskjoldii var. wormskjoldii American alpine speedwell

Vicia americana American vetch

Vicia americana ssp. americana American vetch

Vicia sativa Garden vetch

Vicia sativa ssp. nigra Garden vetch

Viola adunca Hookedspur violet

Viola adunca var. adunca Hookedspur violet

Viola biflora Arctic yellow violet

Viola biflora ssp. biflora Arctic yellow violet

Viola canadensis Canadian white violet

Viola canadensis var. scopulorum Canadian white violet

Viola labradorica Alpine violet

Viola macloskeyi Small white violet

Viola macloskeyi ssp. pallens Smooth white violet

Viola nephrophylla Northern bog violet

Viola renifolia White violet

Woodsia oregana Oregon cliff fern

Woodsia oregana ssp. cathcartiana Oregon cliff fern

Woodsia scopulina Rocky Mountain woodsia

Yucca glauca Soapweed yucca

Zigadenus elegans Mountain deathcamas

Zigadenus elegans ssp. elegans Mountain deathcamas

Appendix E

Section 7 Biological Evaluation

Section 7 of the Endangered Species Act requires that Federal agencies, including the Service, consider the 

effects of their actions on threatened and endangered species. Our Colorado Ecological Services Field Office is 

responsible for section 7 consultation for the SLVCA project area. 

We conducted informal intra-Service consultation during development of the draft EA and LPP in 2012, and the Colorado Ecological Services Field 

Office concurred with our determination that authorization of the SLVCA “may affect, but is not likely to adversely affect” Endangered Species Act–protected species. Because of changes to the status of candidate species that were the subject of that consultation, in November 2013 we sought and received concurrence that the 

project still meets the same determination. 
134 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico
Appendix E—Section 7 Biological Evaluation 135
136 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico
Appendix E—Section 7 Biological Evaluation 137
138 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico
Appendix E—Section 7 Biological Evaluation 139
140 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico
Appendix E—Section 7 Biological Evaluation 141
142 Land Protection Plan for the San Luis Valley Conservation Area, Colorado and New Mexico
Appendix E—Section 7 Biological Evaluation 143

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