Draft Environmental Assessment and 

Land Protection Plan

San Luis Valley Conservation Area

Colorado and New Mexico

May 2012

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

Division of Refuge Planning

134 Union Boulevard, Suite 300

Lakewood, CO 80228

303 /236 8145
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 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 530,000 

acres in conservation easements and a limited amount of fee-title within the project boundary. 

Both documents, which stand alone, are contained within this volume. 

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

Ownership information may not be complete. 
Contents

Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V

Environmental Assessment

Chapter 1 — Purpose of and Need for Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Proposed Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Decisions to Be Made . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Issues Identified and Selected for Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Related Actions and Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

San Luis Valley National Wildlife Refuge Complex (Service) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

U.S. Forest Service (USFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Bureau of Land Management (BLM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

National Park Service (NPS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Natural Resources Conservation Service (NRCS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

State of Colorado . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Land Trusts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

National Wildlife Refuge System and Authorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Chapter 2 — Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Alternatives Considered but Eliminated from Further Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Voluntary Landowner Zoning or County Zoning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Management by Others . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Fee-Title Acquisition Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Conservation Easements Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Chapter 3 — Affected Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Physical Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Minerals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Water and Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Biological Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Plant Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Upland Vegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Wildlife . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Cultural Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Prehistory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Early History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Political Boundaries, Land Grants, and Public Lands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Native Peoples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
ii Draft EA and LPP Draft EA and LPP, San Luis V, San Luis Valley Conservation Area, Colorado and New Mexico alley Conservation Area, Colorado and New Mexico

Settlement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Summary of Known Historic Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Socioeconomic Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Socioeconomic Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Land Use and Ownership Changes Surrounding the Refuge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

SLVCA Land Conservation Efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Water Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Chapter 4 — Environmental Consequences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Effects on the Physical Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Effects on the Biological Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Effects on Cultural Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Effects on the Socioeconomic Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Unavoidable Adverse Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Irreversible and Irretrievable Commitment of Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Short-Term versus Long-Term Productivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Cumulative Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Past, Present, and Reasonably Foreseeable Future Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Alternative A (No Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Alternative B (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Chapter 5 . — Coordination and Environmental Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Agency Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Contaminants and Hazardous Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

National Environmental Policy Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Environmental Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Distribution and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Land Protection Plan

Chapter 1 — Introduction and Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Purpose of the SLVCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

San Luis Valley Refuge Complex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Alamosa and Monte Vista NWRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Baca NWR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Issues Identified and Selected for Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
iii

Public Review of and Comments on the Draft EA and LPP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

National Wildlife Refuge System and Authorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Related Actions and Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Habitat Protection and the Easement Acquisition Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Conservation Easements and Other Acquisitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Chapter 2 — Area Description and Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Chapter 3 — Threats to and Status of Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Threats to Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Invasive Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Water Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Cultural Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Climate Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Effects of the SLVCA on the Natural and Human Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Chapter 4 — Project Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Land Protection Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

No Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Conservation Easements and Limited Fee-Title Acquisition (Proposed Action) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Project Objectives and Actions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Easement Terms and Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Contaminants or Hazardous Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Acquisition Funding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Protection Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Species-Habitat Mapping Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Landscape Prioritization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Evaluation of Easement Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Ecosystem Management and Landscape Conservation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Incorporating Science and Strategic Habitat Conservation in the SLVCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Socioeconomic Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Public Involvement and Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Scoping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Distribution and Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Appendixes

Appendix A. List of Preparers and Reviewers .......................................................... 79

Appendix B. Species List of the San Luis Valley Conservation Area ......................................... 81

Contents
iV Draft 

FIGURES

Figure 1. The SLVCA will be part of a broader network of public and private conservation lands. ...................4

Figure 2. The SLVCA captures the upper headwaters of the Rio Grande, the fourth longest river in the United States. .10

Figure 3. An overview of the basic land cover and vegetation in the SLVCA. ...................................12

Figure 4. Dozens of species of migratory waterbirds forage and/or nest in seasonal and temporary wetlands. .......13

Figure 5. The riparian corridors of the San Luis Valley serve as wildlife corridors and provide nesting habitat 

for the endangered southwestern willow flycatcher. ..................................................14

Figure 6. The Rio Grande cutthroat trout, once found throughout the Rio Grande and Pecos River watersheds, 

is now only found in scattered cold water, high elevation streams . ......................................16

Figure 7. The endangered southwestern willow flycatcher nests in the willows along the Rio Grande and 

its tributaries . ................................................................................16

Figure 8. The wetlands and fields of the SLVCA are an important stopover habitat for migrating sandhill cranes. .....17

Figure 9. The semi-desert shrublands and adjoining Sangre de Cristo Mountains near Baca NWR are home 

to thousands of elk. ............................................................................18

Figure 10. The ranching heritage of the San Luis Valley extends back into the 17th century, as evidenced 

by the national historic register listed Trujillo Homestead on Baca NWR . .................................19

Figure 11. The San Luis Valley contains archaeological sites extending thousands of years into prehistory. ..........20

Figure 12. Agriculture practices such as haying and grazing are a primary component of the economy in 

the San Luis Valley, and often provide habitat for wildlife as well .......................................30

Figure 1. An overview of the general land cover of the SLVCA. .............................................46

Figure 2. Water is a critical resource for 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.. . . . . . . . . . . . . . . . .52

Figure 3. The SLVCA forms part of a broader network of public and private conservation lands, and by further 

networking these lands will contribute to the ability of the species and habitats of the Southern Rocky 

Mountains to adapt to climate change. ............................................................54

Figure 4. Potential management units of the SLVCA, with the Closed Basin in tan, the southern Sangre de 

Cristo Mountain watersheds in green, and the remaining Rio Grande watershed in blue.. ....................56

Figure 5. Southwestern Willow Flycatcher and Canada Lynx Habitat in the San Luis Valley Conservation Area. .......58

Figure 6. Rio Grande Cutthroat Trout Presence in the San Luis Valley Conservation Area. ........................59

Figure 7. Gunnison Sage Grouse Presence in the San Luis Valley Conservation Area. ...........................60

Figure 8. Wilson’s Phalarope Habitat Prioritization in the San Luis Valley Conservation Area.. .....................61

Figure 9. American Bittern Habitat Prioritization in the San Luis Valley Conservation Area. .......................62

Figure 10. Sage Thrasher Habitat Prioritization in the San Luis Valley Conservation Area. ........................63

Figure 11. Areas of overall conservation need. Relative irreplaceability indicates what proportion of models 

in which that particular conservation unit was selected. ...............................................64

EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

TABLES

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

Valley Conservation Area (SLVCA).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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

that contain the San Luis Valley Conservation Area (SLVCA).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

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

Luis Valley Conservation Area (SLVCA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Table 4. Social and economic impacts of conservation easements and fee-title acquisitions.. . . . . . . . . . . . . . . . . . . . . 42
Abbreviations

BLM Bureau of Land Management

CCP Comprehensive Conservation Plan

CWCB Colorado Water Conservation Board

EA Environmental Assessment

LPP Land Protection Plan

NEPA National Environmental Policy Act

NAWCA North American Wetland Conservation Act

NRCS Natural Resource Conservation Service

NWR National Wildlife Refuge

SLVCA San Luis Valley Conservation Area

USFWS US Fish and Wildlife Service

USGS United States Geological Survey

WRP Wetland Reserve Program

 Environmental Assessment 

Chapter 1 — Purpose of 

and Need for Action

This Environmental Assessment (EA) documents the 

purpose of and the issues, alternatives, and analysis 

for the proposed San Luis Valley Conservation Area 

(SLVCA). The SLVCA would be located largely in 

southern Colorado, but a small portion (less than 10 

percent) would be in northern New Mexico. Section 

1 provides background information and describes the 

conditions that led to the U.S. Fish and Wildlife Service 

(Service or USFWS) proposal to create the SLVCA 

for the protection of important wetland and upland 

habitats, primarily through conservation easements 

with willing landowners.

Introduction

The proposed SLVCA is a landscape-level strategic 

habitat conservation initiative within the Southern 

Rockies Landscape Conservation Cooperative. The 

SLVCA would encompass the headwaters and upper 

portions of the Rio Grande in southern Colorado and 

a small part of northern New Mexico. 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 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, 

numerous species of migrating and nesting waterfowl, 

and 95 percent of the Rocky Mountain population of 

greater sandhill crane.

Anthropogenic [human-caused] practices such as 

agriculture have resulted in substantial changes to 

the hydrology of the San Luis Valley. These effects 

have been exacerbated in recent years by a changing 

climate and lower precipitation amounts. 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 substantial loss of wetland habitat. Many of the 

remaining wetlands and their associated wildlife are 

maintained either as an accidental byproduct of agricultural water use or as an intentional habitat type 

through active manipulation such as irrigation with 

surface- and groundwater and the construction of 

dikes and ditches. 

The remaining wetlands, and the low human population density associated with the largely agricultural 

economy of the valley, have resulted in the San Luis 

Valley’s maintaining a significant portion of its biological value, particularly for migratory birds. However, 

rising agricultural costs, including those resulting from 

the recent requirement to augment surface flows to 

offset the impacts of ground water use, have led to 

an unsettled agricultural economy. The potential for 

farmers and ranchers to sell water rights from their 

lands or even convert current land use practices from 

agricultural to residential, industrial, or municipal 

uses will continue to grow and threaten the biological 

integrity of the San Luis Valley.

Proposed Action

The Service proposes to create the 5.2-million-acre 

SLVCA to conserve vital wildlife habitats and migration corridors through voluntary conservation easements and a limited amount of fee-title acquisition. 

The SLVCA acquisitions will focus on the protection 

of wetlands, riparian corridors, and certain uplands in 

the valley through the purchase of up to 500,000 acres 

of conservation easements. Up to an additional 30,000 

acres of fee-title acquisition from willing sellers has 

been proposed and was approved as part of the Preliminary Project Proposal for this project. However, 

the present intent is to use fee-title acquisition only in 

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 (e.g., 

acquisition of surface water rights for augmentation).

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, exercise of water rights 
2 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

associated with these lands could be changed only if 

the proposed changes would be beneficial to wildlife.

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 off-parcel sale of surface water

■ 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

■ protect, restore, or, when necessary, emulate the 

historic hydrologic regime of the valley to ensure 

the presence of wildlife habitat

The Service will phase in implementation of the overall 

project. We anticipate focusing first on the southern 

Sangre de Cristo mountains, with conservation on 

the valley floor to follow. During this comment period we want to hear from all interested parties and 

partners to ensure we understand and consider any 

concerns or comments about the acquisition of easements in these areas. A Habitat Conservation Plan 

for the southwestern willow flycatcher is currently 

in development by local governments and pertains 

to the valley floor. This and considerations about the 

actual easement language as it relates to water use 

and rights may take longer to resolve. These issues 

are less likely to be concerns in the southern Sangre 

de Cristo mountains. Therefore, we anticipate that, if 

the overall plan is approved, we will focus our initial 

implementation efforts there. 

Decisions to Be Made

Based on the analysis provided in this draft EA and 

following public comment and revision, the Regional 

Director of the Service will make two decisions:

1. Determine whether the Service should establish 

the SLVCA, in accordance with its land protection 

planning policy.

2. If yes, determine whether the selected alternative 

will have a significant impact on the quality of the 

human environment. This decision is required by 

the National Environmental Policy Act (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

The Service solicited comments about the SLVCA 

from the public through direct mailings, news releases, 

public meetings, and direct contacts.

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

period for the general 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 co-planning 

and NEPA review for the Comprehensive Conservation Plan (CCP) and Land Protection Plan 

(LPP) for the San Luis Valley National Wildlife 

Refuge Complex. 

■ 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 

the Director of the Service presented as being embodied by the SLVCA. Questions were answered 
Chapter 1 — Purpose and Need for Action 3

and comments taken at a breakout session following the main meeting.

The project’s planning Web site <http://www.fws.gov/

alamosa/planning> was established in early March 

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 topics 

and issues identified during the scoping process and 

during internal conversations among the SLVCA 

planning team are:

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

and shrublands, of the San Luis Valley, while also 

maintaining the rural agricultural aesthetic that 

defines 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.

■ Develop partnerships for land protection.

■ How will the public be able to use lands protected 

under the SLVCA?

■ Ensure 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?

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

visibility effects. 

Related Actions and 

Activities

The San Luis Valley contains many public lands and 

private protected areas, some of which are contiguous with other protected areas and some of which 

are isolated. As illustrated in Figure 1, several existing State, Federal, and private land trust programs 

promote the conservation of habitats in the SLVCA. 

SAN LUIS VALLEY NATIONAL WILDLIFE REFUGE 

COMPLEX (SERVICE)

The San Luis Valley National Wildlife Refuge Complex includes three existing units: the Alamosa, Baca, 

and Monte Vista National Wildlife Refuges (NWRs). 

These refuges were established for different purposes, 

as described in Section 1.1 of the LPP in this volume, 

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. Limited water availability presents significant challenges, particularly given a changing climate 

and new State of Colorado requirements for ground 

water augmentation. A secondary goal of the SLVCA 

is to help restore the hydrology of the San Luis Valley both on and off existing refuges to help ameliorate 

some of this problem.

U .S . FOREST SERVICE (USFS)

The San Isabel and Rio Grande National Forests border the SLVCA to the north, east, and west. These 

forests contain nearly 3 million acres of public lands 

in the Sangre de Cristo, Saguache, and San Juan 

mountains. The forests contain habitat ranging from 

pinyon-juniper savanna up to alpine tundra and scree 

fields at elevations over 14,000 feet. Much of this is 

designated wilderness area. These national forests are 

important habitat for Federal trust species, including 

Canada lynx and Rio Grande cutthroat trout, and for 

non-listed but climate-change-imperiled species, such 

as American pika and white-tailed ptarmigan.

BUREAU OF LAND MANAGEMENT (BLM)

Much of the land between the National Forest boundaries and the largely private valley floor is administered 

by the BLM as the San Luis Resource Area. The BLM 

is actively working to restore the historic playa wetlands in the South San Luis Lakes and Blanca Wetlands 

areas, the latter of which they have designated as an 

Area of Critical Ecological 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.

NATIONAL PARK SERVICE (NPS)

Bordering Baca NWR is the Great Sand Dunes National Park and Preserve (NPP). Together these comanaged NPS units protect approximately 150,000 

acres, from valley floor rabbitbrush scrub and the tallest sand dunes in North America to peaks over 13,000 

feet in the Sangre de Cristo Mountains. 
4 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 1 . The SLVCA will be part of a broader network of public and private conservation lands .
Chapter 1 — Purpose and Need for Action 5

NATURAL RESOURCES CONSERVATION SERVICE 

(NRCS)

The NRCS actively works in the 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 their wetland restoration efforts.

STATE OF COLORADO

The State of Colorado owns thousands of acres throughout the project area, and also 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 NWR and west 

of Great Sand Dunes NPP is San Luis Lakes State 

Park, which provides important habitat for migratory 

birds as well as opportunities for wildlife-dependent 

recreation and watersports.

LAND TRUSTS

Tens of thousands of acres are protected in either fee 

title or easement programs funded and/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 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 those 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 

NWR and Great Sand Dunes NPP. 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.

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 appropriate, 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 additional wildlife habitat in the 

SLVCA would 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)

■ Endangered Species Act (1973)

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

■ Alamosa-Monte Vista National Wildlife Refuge 

Complex Comprehensive Conservation Plan (2003)

■ Baca National Wildlife Refuge Conceptual Management Plan (2005)

The acquisition authorities for the proposed easements 

and property acquisition are the U.S. Fish and Wildlife Act of 1956 (16 U.S.C. 742a-j) and the National 

Wildlife Refuge System Administration Act of 1966 

(16 U.S.C. 668dd-668ee), as amended. Land would 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. 

The Service could also purchase land interest through 

the use of duck stamp revenue from the Migratory 

Bird Hunting and Conservation Stamp Act of 1934. 

There could also be additional money to acquire lands, 

water, and interests for fish and wildlife conservation 

purposes as identified by Congress or donations from 

nonprofit organizations. Any acquisition from willing 

sellers would be subject to available funding.

Chapter 2 — Alternatives

This chapter 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 appropriate alternatives to recommend courses 

of action in any proposal which 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 eliminated 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 additional 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 the Rio Grande Headwaters Trust. 

Alternative B (Proposed 

Action)

Under the proposed action, the Service would establish the SLVCA in southern Colorado and northern 

New Mexico. The project boundary encompasses approximately 5.2 million acres. Within this boundary, 

the Service would strategically acquire from willing 

sellers perpetual conservation easements on up to 

500,000 acres and potentially acquire fee-title 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 portion 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 500,000 acres through 

conservation easements. 

In instances where boundary adjustment or additional acquisition would simplify the management of 

or better meet the objectives of existing refuges (e.g. 

acquiring surface water rights for augmentation), the 

Service will consider the acquisition of up to 30,000 

acres in fee title. 

Potential easements or fee-title lands will be prioritized based on wildlife needs in the project area, which 

include areas of 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. The LPP in the second part of this volume 

describes these priorities in detail.

Nothing in this alternative would preclude the 

subdivision of the SLVCA into separate management 

units to simplify the administration of easements and 

fee-title lands acquired as part of the SLVCA if deemed 

necessary by the Service.
8 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

Alternatives Considered 

but Eliminated from Further 

Analysis

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. 

This conversion has often been accompanied by the 

replacement of flood irrigation practices with centerpivot irrigation. Although center-pivot irrigation offers 

on-site 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

A substantial portion of the SLVCA (some 44 percent) is 

under public ownership already; current land managers 

include the Colorado Parks and Wildlife, the Colorado 

State Land Board, the BLM, the NPS, the USFS, and 

the Service. Additional land is conserved in fee title by 

The Nature Conservancy, and conservation easements 

are held by Ducks Unlimited, Rio Grande Headwaters Trust, the NRCS, and the Colorado Parks and 

Wildlife, among others. There are active conservation 

initiatives underway by these organizations, but none 

has the scope necessary to achieve the conservation 

objectives of the SLVCA, nor do other organizations 

have the same wildlife habitat objectives.

FEE-TITLE ACQUISITION ONLY

Much of the publicly owned land mentioned in the 

previous section has been managed for conservation purposes for decades; indeed, Great Sand Dunes 

NPP 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 management 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 reasons as well as 

the expense of managing additional public lands, it is 

the Service’s policy to acquire the minimum interest 

necessary to reach conservation objectives.

CONSERVATION EASEMENTS ONLY

Conservation easements can be used to achieve conservation objectives while preserving working landscapes, such as farms and ranches. They are more cost 

effective, socially acceptable, and politically popular 

than acquiring fee-title land, and often promote the 

preservation of the unfragmented, quality habitat we 

seek to protect. However, there may be circumstances 

in which the Service’s goals may not be met with an 

easement-only conservation area, particularly in circumstances where acquisitions would serve to enhance 

the management efficiency of existing national wildlife 

refuges or to secure water rights to benefit wildlife 

on existing refuges.
Chapter 3 — Affected Environment

This chapter describes the biological, cultural, and 

socioeconomic resources of the SLVCA that could be 

affected by the no-action alternative (alternative A) 

and the proposed action (alternative B). The SLVCA 

consists of 5.2 million acres within the Southern Rockies and Arizona/New Mexico Plateau ecoregions (U.S. 

Environmental Protection Agency 2011). The project 

encompasses significant portions of seven counties in 

southern Colorado as well as small parts of two counties in northern New Mexico. Just over 50 percent of 

the total project area is publicly owned; however, the 

distribution of public/private ownership is uneven, with 

over 90 percent of Mineral County administered by 

the USFS, but less than 1 percent of Costilla County 

in State or Federal ownership. The project boundary 

is defined by the headwaters hydrologic unit (HUC 

6) of the Rio Grande. 

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 playa wetlands 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

GEOLOGY

The San Luis Valley is part of the much larger Rio 

Grande Rift Zone, which 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 portion 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 deposits 

consist of sedimentary rocks that inter-finger with 

volcanic deposits. Quaternary deposits include pediments along the mountain fronts, alluvium, and sand 

dunes (USFWS 2011). 

MINERALS

Sand and gravel are the major mineral commodities 

mined in the vicinity of 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, 

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

Surface Water

The SLVCA contains the upper headwaters of the Rio 

Grande watershed (Figure 2). 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 

Conejos, San Antonio, and Rio Grande rivers.

A portion of the northern valley, known as the 

Closed Basin or Sump, does not 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 San Luis and Saguache creek drainage basins. Water enters the Closed 

Basin through precipitation and snowmelt from the 

4,700 square miles of watershed in the surrounding 
10 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 2 . The SLVCA captures the upper headwaters of the Rio Grande, the fourth longest river in the United States .
Chapter 3 — Affected Environment 11

mountains. Water exits primarily through evapotranspiration. Approximately 7,000 miles of stream channels and ditches flow through the valley. Surface water 

flows into San Luis Creek, which flows generally to 

the south. There is no outlet, so water is impounded 

in San Luis Lake and associated lakes in an area south 

of the Baca NWR (USFWS 2011).

Groundwater

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 the aquifer system that 

stretches from Saguache County, Colorado, to West 

Texas (Robson and Banta 1995). The San Luis Valley 

is estimated to contain more than 2 billion acre-feet of 

ground water in storage, with more than 140 million 

acre-feet estimated to be recoverable. The principal 

use of groundwater is agricultural (USFWS 2012).

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, though the lines between these features are not 

absolute. Combined, these two aquifer systems are 

contained in valley-fill that can be as much as 30,000 

feet thick (Brendle 2002). 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 Sangre de Cristo Mountains. Discharge 

from the confined aquifer is from ground water withdrawals, ground water flow to the south, and upward 

leakage through the confining bed (USFWS 2012).

A third aquifer system covers approximately 3,000 

square miles in the Closed Basin in the northern part 

of the valley. This aquifer system has no natural surface water drain. The U.S. Bureau of Reclamation’s 

Closed Basin Project extracts ground water from 

the sump. The water levels in the unconfined aquifer 

in the Closed Basin are declining and ground water 

withdrawal is exceeding recharge (Rio Grande Water 

Conservation District 2012). Ground water from the 

Closed Basin Project is carried in the Closed Basin 

Canal, which starts in the central San Luis Valley, 

passes south through Baca NWR, and ends at the Rio 

Grande on Alamosa NWR land. Salvaged Closed Basin ground water helps Colorado meet its interstate 

compact with New Mexico and Texas (USFWS 2012). 

CLIMATE

The climate of the San Luis Valley is consistent with 

its high mountain desert setting, with substantial 24-

hour temperature swings due to 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. 

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

The vegetation across the project area varies greatly, 

depending on hydrology, slope, aspect, and elevation. 

See Figure 3 for an overview of general landcover. The 

San Luis Valley’s hydrology is strongly influenced by 

the surface runoff and ground water flows from the 

surrounding mountains. This hydrology has 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 six Colorado counties that 

constitute the majority of the project area (Saguache, 

Mineral, Rio Grande, Costilla, Conejos, and Alamosa) 

contain 1,132 species of plants (Appendix B; Colorado 

State University Herbarium 2012), which is more than 

a third of the total plant species present in Colorado. 

Wetlands

Wet Meadows. Wet meadow habitat is naturally present in the San Luis Valley in 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 wet meadows have also expanded due 
12 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 3 . An overview of the basic land cover and vegetation in the SLVCA .
Chapter 3 — Affected Environment 13

Figure 4 . Dozens of species of migratory waterbirds forage and/or nest in seasonal and temporary wetlands .

© Joe Zinn

to artificial irrigation for hay fields and cattle grazing. 

These agricultural uses, while not without their own 

problems, do 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 numerous species of waterfowl 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.

Playa Wetlands. Playa wetlands form in areas where 

streams flow into closed basins, in areas where seasonally high water tables result in surface discharge 

or capillary flow from aquifers, or both (Rocchio 2005). 

In the San Luis Valley, playa wetlands are found both 

in the closed basin at the termini of San Luis and Saguache Creeks on and near the Baca NWR, and in and 

around the Blanca Wetlands, which are managed by 

BLM. These wetlands are ephemeral or temporary, 

and since the water regime of the valley has been 

altered by human activity, they may remain dry in 

years of below average precipitation. The ephemeral 

nature of these wetlands adds to their uniqueness and 

their high productivity when inundated. During wet 

years, playas fill with rainfall during thunderstorms 

and with runoff from spring snowmelt in the surrounding mountains, and then slowly dry until the next wet 

season. This flooding and drying cycle provides for 

the nutrient cycling conditions ideal for invertebrates 

such as tadpole shrimp, which is a valuable food resource for wildlife, particularly migratory shorebirds. 

In particularly wet years, these wetlands are some of 

the most productive wetlands in the valley (Cooper 

and Severn 1992, as cited in USFWS 2005). Greasewood and rubber rabbitbrush with an understory of 

saltgrass and western wheatgrass typically surround 

pans that are bare or vegetated with saltgrass. Barren salt flats may be a component of playa wetland 

systems and can be important to foraging and nesting 

shorebirds (USFWS 2005). 

Seasonal and Semipermanent Wetlands. Seasonal and 

semipermanent wetlands have hydrologic regimes 

that 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 

(Figure 4). Tall emergent wetlands can also be seasonal 

and are typically dominated by bulrush and cattails. 
14 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

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 

geese, American bitterns, snowy and cattle egrets, 

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

marsh passerines 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.

Riparian Habitats

Riparian habitat includes trees, shrubs, and other 

streamside vegetation and is associated with intermittent and perennial waterways (Figure 5). This 

community may flood every year. Its historic extent 

on the valley floor has been reduced due to surface 

water diversion. Woody riparian habitat is sensitive 

to excessive grazing, which limits regeneration of the 

dominant willows and narrowleaf cottonwood trees. 

Shrubs that contribute to the structural diversity 

of riparian habitat include red-osier 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 stream bank stabilization 

provided by riparian vegetation is important in maintaining 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.

Figure 5 . The riparian corridors of the San Luis Valley serve as wildlife corridors and provide nesting habitat for 

the endangered southwestern willow flycatcher .

© Joe Zinn

UPLAND VEGETATION

Semi-desert 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 than these, rabbitbrush shrublands are 

desert scrub and shrub-steppe habitats that have a 

significant cover of big sagebrush and/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 semi-desert shrublands due to 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 
Chapter 3 — Affected Environment 15

the declining sage thrasher and the Endangered Species Act candidate Gunnison sage-grouse.

Montane Forests. Above the semi-desert 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.” Pinyon-juniper 

woodland is particularly threatened by the spread of 

invasive grasses that increase its susceptibility to fire 

(Colorado Natural Heritage Program and 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; 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 pinyonjuniper associated species include black-throated gray 

warbler and juniper titmouse.

As the elevation increases, the forest becomes a 

mixed conifer forest, sometimes with an aspen component, and finally becomes a subalpine spruce-fir forest. 

The vast majority of land at the higher elevations is 

under the management of the USFS, with the exception of areas of Costilla County, where it is largely 

part of a handful of large private ranches. These forests are home to a number of bird species, including 

olive-sided flycatcher, yellow warbler, and mountain 

chickadee. These higher elevation forests also provide habitat and migration corridors for a number of 

important large mammals such as elk, black bear, and 

the threatened Canada lynx.

WILDLIFE

The diverse mix of wetland, riparian, shrubland, and 

forest 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 

B 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 semi-desert 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 due to 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).

Fish and Aquatic Species

The project area contains the headwaters of the Rio 

Grande. The Rio Grande and its tributaries, the streams 

of the San Luis Closed Basin, 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 a direct result of anthropogenic changes to the hydrology of the valley, not the 

least of which are water diversions. These impacts 

have been magnified by persistent drought conditions 

since the 1990s. The SLVCA easement program will 

assist in the conservation of these species by ensuring 

that water use is tied to the land on which the easement is purchased.

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 in 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 NWR. 

The Colorado Natural Heritage Program considers 

the Rio Grande chub to be an S1 (critically imperiled) 

species. It is thought to have declined due to habitat 

fragmentation by impoundments for diversions, habitat 

destruction due to poor land use practices, and predation by, and competition with, introduced fish species 

(Rees et al. 2005a). 

The Rio Grande sucker had a historic 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 reintroduced to several 

additional streams. It is considered a State endangered 

fish in Colorado (Rees et al. 2005b).

In historical times, Rio Grande cutthroat trout 

(Figure 6) 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 

mid-afternoon,” which the fishermen shipped off to a 

restaurant in Denver (Sanford 1933). At present, 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 historic range. Threats 

to the species include competition and hybridization 

with, and predation by, introduced trout; reduction 

in habitat quality due to water diversions and other 
16 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

hydrological changes; and changes in stream temperature due to human water use and global climate 

change.1 It is currently a candidate species under 

the Federal Endangered Species Act; a decision on 

whether to list the species is due in 2014.

Some 57 species of non-native 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 

includes rainbow, golden, brook, and brown trout; 

northern pike; bluegill; pumpkinseed; yellow bullhead; 

common carp; large and small mouth bass; blue, flathead, and channel catfish; walleye; and yellow perch. 

Non-game species such as white suckers, Mozambique 

tilapia, grass carp, American eel, and even neotropical tetras and armored catfish have become naturalized in the Rio Grande drainage as well (USGS 2012).

Figure 6 . The Rio Grande cutthroat trout, once 

found throughout the Rio Grande and Pecos River 

watersheds, is now only found in scattered cold 

water, high elevation streams .

© Colorado Parks and Wildlife

Figure 7 . The endangered southwestern willow 

flycatcher nests in the willows along the Rio Grande 

and its tributaries .

© Suzanne Langbridge/USGS

Birds

The wetlands, riparian corridors, uplands, and forests 

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 

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

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, a Federal candidate for listing 

as endangered. Olive-sided flycatchers breed in the 

coniferous forests of the mountains surrounding the 

valley. The southwestern willow flycatcher (shown in 

Figure 7), a subspecies of the more widespread willow 

flycatcher, 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 additional 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 

and Central 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 USFWS 

Migratory Bird Program and/or are USFWS 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 
Chapter 3 — Affected Environment 17

is regionally important to 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 (S. Johnson, USFWS Migratory Birds, 

personal communication 2012). The secretive American bittern breeds in the valley, and has experienced 

population declines throughout its range, likely due to 

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 the Monte Vista NWR, 

where they are the focus of an annual crane festival 

and a draw for thousands of tourists every year (Figure 

8). 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 

and long-eared owls, red-tailed hawks, American kestrels, and Swainson’s hawks (USFWS 2011). The latter 

species is a bird of conservation concern in USFWS 

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, and golden 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 portions 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; this species is 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 that these species have life history needs 

Figure 8 . The wetlands and fields of the SLVCA are an important stopover habitat for migrating sandhill cranes .

© Joe Zinn
18 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

that 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 currently a candidate for listing 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 

at present (Schroeder et al. 2004), and the Colorado 

Parks and Wildlife has identified that some of this 

former range is still potential habitat for the species 

(Gunnison Sage-Grouse Rangewide Steering Committee 2005). This potential range is mostly in Conejos 

and Costilla Counties, Colorado, but since the area 

of potential habitat crosses the State border, there 

is also some potential habitat in Rio Arriba and Taos 

Counties, New Mexico. 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 a USFWS Migratory Bird focal 

species and a USFWS 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 (Oyler-McCance et al. 2001), so 

this species is likely to benefit from the protection of 

remaining potential habitat that the proposed action 

would 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 

would likely benefit from conservation of sagebrush 

and steppe habitat as well.

Figure 9 . The semi-desert shrublands and adjoining Sangre de Cristo Mountains near Baca NWR are home to 

thousands of elk .

USFWS

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 component 

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 currently 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). These megafauna provide 

opportunities for hunting and wildlife viewing, 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. The elk herd on the east side of the valley 

(Figure 9) has been estimated to number approximately 5,000 animals (R. Rivale, Wildlife Biologist 

– CPW, 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 
Chapter 3 — Affected Environment 19

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. 

Of conservation concern is the Gunnison’s prairie dog, 

which inhabits the valley floor. This species has suffered a sharp decline for reasons that include human 

persecution and outbreaks of plague. It is a candidate 

for Federal Endangered Species Act protection, and 

a listing decision will be made following a genetic reevaluation of its taxonomic status.2

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. 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, 

it 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 College in Alamosa, 

Colorado. Similarly, the gray wolf historically hunted 

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 demonstrates the potential ecological benefits of natural or human-facilitated 

reintroduction of wolves, particularly on vegetation 

adversely affected by unnaturally high elk browsing 

(Ripple and Beschta 2012). However, this possibility 

was received with opposition by some local ranchers 

and some members of the big game hunting community 

during scoping meetings for the CCP for the San Luis 

Valley NWR Complex in 2012; reintroduction will be 

discussed as part of one alternative during the NEPA 

review for the CCP. 

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 in the 

San Luis Valley during the summer and migrate to 

2 Federal Register 76, No. 207. 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. 66389

warmer climates during the winter. The presence of 

mature cottonwood riparian forests likely maintains 

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. 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 for over 

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 (Figure 10). 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. 

Figure 10 . The ranching heritage of the San Luis Valley

extends back into the 17th century, as evidenced by 

the national historic register listed Trujillo Homestead

on Baca NWR .

an Ness/USFWS Meg V
20 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

PREHISTORY

Paleo-Indian Stage

Current archaeological evidence indicates 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 additional data become available, the 

stage generally lasted until about 7,500 years ago.

Information from the Colorado Office of Archaeology and Historic Preservation indicates that 62 paleoIndian resources have been identified in the proposed 

SLVCA. 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 on the western edge of 

the proposed 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 (Figure 11). 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 NPP 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 paleoIndian 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 

Figure 11 . The San Luis Valley contains archaeological sites extending thousands of years into prehistory .

an Ness/USFWS Meg V
Chapter 3 — Affected Environment 21

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 indicate oscillations 

in bison numbers in response to climatic conditions 

(Creel et al. 1990). Although additional 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 long-term 

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 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 portion of the study area. As 

with the earlier inhabitants, the Archaic peoples made 

extensive use of the valley’s wetland resources and 

occupied the rockshelters and several high-altitude 

locations found in the surrounding mountains. Speaking of Archaic sites in the northeastern portion 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 very mobile, the population increasingly 

made short-term 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 numerous 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 historic period.

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 numerous 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 utilized 

and/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 post-contact goods. 

EARLY HISTORY

The Historic 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 historic 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, 
22 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

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 Northern 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 numerous 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 historic 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 concerning the native peoples, topography, and environment (Colville 1995). After leaving 

Santa Fe, De Vargas followed the North Branch of the 

Spanish Trail northward, travelling 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/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 mid-summer.

Notable features of the de Vargas journal include 

the advantageous yet temporary alliance of de Vargas’ 

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 portions 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 
Chapter 3 — Affected Environment 23

“...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 concerning 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 

portion 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, antelope, otter, big-horned 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 numerous 

small Spanish settlements that dotted the landscape 

and interactions with the native peoples.

Fowler recorded an exceptionally astute observation while crossing the southern portion 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.

Numerous 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: 

■ 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 U.S. negotiates the Adams-Onis 

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.
24 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

1837 The United States recognizes the Republic of Texas, including the San Luis 

Valley.

1845 The 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 Mexico–United States border except for the 

later 1853 Gadsden Purchase (southern 

Arizona and southern New Mexico).

1850 Amid much controversy over 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 previously 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, numerous 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 

maintain 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 numerous 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 over 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 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 grants, 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 U.S. 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 portion established as the Baca National Wildlife Refuge in 2000. 

Slightly under half of the SLVCA is publically 

owned. This includes large portions 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 currently 

owns large parcels of land in the area, primarily in 

the western and northern parts of the valley floor. 

Great Sand Dunes NPP 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 (2000), 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 post-contact 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 currently represented in the valley, today they 

comprise 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 
Chapter 3 — Affected Environment 25

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 to 1858) and Fort 

Garland (1858 to 1883) 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 portions 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. 

Numerous 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 U.S. 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 the majority 

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 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 to1875 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 prior to 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)
26 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

The mining boom in the surrounding mountains in 

1859, the completion of the Denver & 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. 

Prior to 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, buffalo, deer, elk, and bighorn sheep (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 concerning the recorded resources in the 

Colorado portion of the SLVCA 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 portion 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 (multi-component) and therefore may be counted more than once. 

It is also important to note that the distribution of 

the known resources often indicates where modern 

activities have mandated cultural resource surveys 

and may also potentially indicate 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 portion of the 

proposed SLVCA. 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 

and/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. 

Over 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 and/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. 
Chapter 3 — Affected Environment 27

Socioeconomic Environment

SOCIOECONOMIC PROFILE

Population

The SLVCA spans nine counties: Alamosa County, 

Conejos County, Costilla County, Hinsdale County, 

Mineral County, Rio Grande County, and Saguache 

County in Colorado and Rio Arriba County and Taos 

County 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). Over the past decade, population 

growth in the region has been slow, and the region has 

experienced some out-migration. 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). Of the seven Colorado counties in the nine-county region, the greatest 

in-migration was experienced in Hinsdale County (7 

percent increase from 2000 levels), and in New Mexico, 

Taos County (10 percent increase from 2000 levels) experienced the largest increase in population. Five of 

the nine counties in the region (Conejos, Rio Arriba, 

Rio Grande, Costilla, and Mineral Counties) experienced negative growth during these years, with the 

greatest out-migration occurring in Mineral County 

(14 percent decrease from 2000 levels) (U.S. Census 

Bureau 2010a). 

Population growth in the nine-county 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). Within the 

nine-county region, the greatest projected increases 

in population are expected to occur in the counties of 

Hinsdale (26 percent), Alamosa (25 percent), and Saguache (18 percent). The smallest projected increases 

are anticipated in the counties of Rio Grande (7 percent) and Costilla (8 percent) (Colorado Department 

of Local Affairs 2002, University of New Mexico 2002).

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

Conservation Area (SLVCA) .

Percentage Percentage 

Persons per square population change population change 

Residents (2010) mile (2010) (2000–2010) (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 17.0 13% 19%

Rio Arriba County 40,246 6.9 -2% 11%

Taos County 32,937 15.0 10% 17%

Sources: U.S. Census Bureau 2010a and †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 region. The prevalence of this ethnic 

group is due to the presence of two large Hispanic 

communities in the local area. The region is home to 

a large population of White residents who identify 

themselves as being of the 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 countywide population on average (U.S. Census 

Bureau 2010a). The occurrence of this race-ethnicity 

pairing in the San Luis Valley may be due to residents 

of Hispano heritage (i.e., descendants from Spaniards) 

(Sangre de Cristo National Heritage Area 2012). Hispanics of Mexican descent also represent a substantial 
28 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

share of the population in Alamosa (26 percent), Conejos (22 percent), Costilla (34 percent), Rio Grande (25 

percent), Saguache (27 percent), and Rio Arriba (21 

percent) Counties (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). Mineral 

County, Colorado, has the largest representation of 

White residents (97 percent of the population), and 

Rio Arriba County has the smallest representation of 

White residents (52 percent of the population) in the 

region. Native Americans and Alaska Natives account 

for 8 percent of the total population of the region, with 

the greatest population of Native Americans located 

in Rio Arriba County (16 percent of the population). 

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). However, among the Colorado 

counties in the local area, only Hinsdale County reported more county residents with at least a bachelor’s degree (42 percent of the countywide population) 

than the State average (36 percent of the statewide 

population). In New Mexico, the same is true of the 

educational attainment in Taos County (30 percent of 

the countywide population with a bachelor’s degree 

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

(U.S. Census Bureau 2010a). 

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

contain the San Luis Valley Conservation Area (SLVCA) .

Median Percentage unemployed‡ Percentage of 

household individuals 

income

(average 

Bachelor’s 

degree or 

below poverty 

(average 

2006-2010)† higher† 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%

Rio Arriba 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

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 with Costilla, Saguache, and Alamosa Counties 

representing the first, second, and third highest poverty levels statewide. Within the nine-county region, 

Hinsdale County, Colorado, had the highest median 

household income ($74,659 per year) and the lowest 

poverty rate (3.7 percent). Costilla County, Colorado, 

had the lowest median household income ($24,388 per 

year) and the highest poverty rate (28.4 percent). 

With the exceptions of Hinsdale and Mineral Counties in Colorado and Taos County in New Mexico, all 

of the counties in the nine-county region had poverty 

levels above the statewide average, with Costilla and 

Alamosa Counties having poverty rates nearly twice 

Colorado’s average. (U.S. Census Bureau 2010b). 

Table 3 shows the percent of employment by sector within the nine-county 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 
Chapter 3 — Affected Environment 29

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).

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

Valley Conservation Area (SLVCA)

Percentage of nine-county region 

Employment sectors employed

Total employment in 2009a 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 assistance 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 due to confidentiality requirements; the table reflects the best and most 

accurate information available

Agriculture, Recreation, and Tourism

Agriculture is a prominent industry in the San Luis 

Valley (Figure 12). 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 (22 percent), and Mineral County, Colorado, had the smallest (2 percent) 

(U.S. Department of Commerce 2010a, U.S. Department of Commerce 2010b [data complied using EPSHDT]). Approximately 29 percent of the land in the 

nine-county region is in agriculture, with Rio Arriba, 

New Mexico, having the largest percentage of land in 

agriculture (39 percent) and Hinsdale County, Colorado, having the smallest (less than 1 percent of total 

land in agriculture) (U.S. Department of Agriculture, 

2009 [data complied using EPS-HDT]).

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 recreationalists, including outdoor recreationalists; visitors to the 

Great Sand Dunes NPP; resort tourists; vacation and 

second home owners; eco-tourists; 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 participated in wildlife-associated 

recreation activities in Colorado and New Mexico in 

2006 (USFWS 2008). It was estimated that residents 

and visitors combined spent $3.8 billion on wildlifeassociated 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 REFUGE 

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 
30 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

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 

on the valley’s periphery 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 complied using EPS-HDT]). 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, the USFS, the BLM, 

the National Park Service, and the State of Colorado. 

The majority 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 local area is urban (NASA 2006 [data complied 

using EPS-HDT]), U.S. Census Bureau 2010a). Major municipalities in the region include Alamosa, San 

Luis, Saguache, Crestone, and Del Norte. Alamosa is 

home to Adams State College and had 8,780 residents 

in 2010, making it the largest municipality in the local 

area; San Luis is a historic community with Hispano 

heritage; Saguache is a ranching community that serves 

as the county seat of Saguache County; Crestone is 

a historic mining town at the base of the Sangre de 

Cristo Mountains in the northern end of the valley 

and is home to several spiritual centers that attract 

a large spiritual community from many different religious and ideological backgrounds; and Del Norte is 

the county seat for Rio Grande County (U.S. Census 

Bureau 2010a, Colorado Tourism Office 2012). 

Figure 12 . Agriculture practices such as haying and grazing are a primary component of the economy in the San 

Luis Valley, and often provide habitat for wildlife as well

USFWS

Changes in Land Use

The SLVCA contains a rich diversity of trust species 

and habitat types, including some of the nation’s most 

dynamic wetlands. The proposed project area supports 

more than 1,300 species of vascular plants, 95 percent 

of the Rocky Mountain population of greater sandhill 

cranes, isolated waterfowl nesting densities exceeding 1,500 nests per square mile, and populations of 

priority species such as the southwestern willow flycatcher, western snowy plover, white-faced ibis, and 

mallard (USFWS 2010a). The SLVCA 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 pristine landscape 

(USFWS 2010a). During this period, livestock grazing, farming, and water development began to affect 
Chapter 3 — Affected Environment 31

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 

has resulted in the loss of significant wetland habitat 

(USFWS 2010a). Most of the remaining wetlands in 

the SLVCA occur on private ranch and farm land and 

are reliant on the water diverted out of rivers and 

creeks or from artesian wells to maintain their value 

to wetland-dependent wildlife (USFWS 2010a). 

Development pressure started to increase during 

the 1990s and early 2000s as land prices and agricultural operation costs in the SLVCA began to rise. To 

continue ranching operations, many rural landowners 

were forced to sell portions of their property for housing and commercial development, creating additional 

fragmentation and loss of critical wildlife habitat, 

including riparian habitat, in the SLVCA (USFWS 

2010a). As agricultural lands are subdivided, the resulting fragmentation can affect habitat use for a wide 

array of waterfowl, shorebirds, colonial waterbirds, 

and songbird species. Many of these species require 

specific habitat conditions for successful reproduction 

and building energy reserves for breeding and migration (USFWS 2010a). 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 often sold with the property, 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 

(USFWS 2010a). Maintaining the current connectedness of the wetland complex through permanent 

protection would limit the risk for species movement 

patterns to be disrupted due to fragmentation and 

would also maintain important migration corridors 

and linkages between seasonal ranges necessary to 

meet the life-history requirements for many wildlife 

species (USFWS 2010a). 

Due to the small agriculture-based human population in the area, however, the landscape has not been 

altered to the same extent as many other western 

regions with more rapid population growth (USFWS 

2010). In recent years, the downturn in the national and 

regional economy has slowed growth and development 

pressures in the SLVCA. 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, Rio Arriba, Rio 

Grande, Costilla, and Mineral Counties) experienced 

negative growth 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 Hinsdale County (26 

percent increase) and Alamosa County (25 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, 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 additional steps to conserve 

wildlife habitat in the San Luis Valley now, while land 

prices are still affordable and irreplaceable habitat has 

not been lost, may be appropriate. Protecting this land 

from development is the only way to ensure the longterm resiliency of the ecosystem and maintain 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 over 7,000 wells and development of one of the world’s largest concentrations 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 chronically exceeds recharge. Because 

legal and political circumstances, new ground water 

rules are currently being developed by the Colorado 

Division of Water Resources and may soon be applied 

to water users in the San Luis Valley (USFWS 2010a). 

Once the new ground water rules are implemented, 

ground water users will be responsible for eliminating 
32 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

injury to senior water rights through a formal augmentation planning process with the State (USFWS 

2010a). In most cases, this will require ground water 

users to acquire, and in many cases, remove senior 

water rights from other properties to augment their 

well use. 

These circumstances threaten healthy riparian 

systems along the Rio Grande, Conejos, and Alamosa 

rivers, where senior water rights are currently used in 

the floodplain. The evolving economic and regulatory 

environment in the SLVCA will 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). 

Additionally, this will increase the State’s difficulty in 

managing water in the Rio Grande and administering 

the Rio Grande Compact. For these reasons, the Rio 

Grande Water Conservation District and other water 

users in the San Luis Valley will support the SLVCA 

in acquiring conservation easements along these rivers (USFWS 2010a). 

Energy development is also an emerging threat to 

wildlife in the SLVCA. Colorado is among the most 

promising sources of solar energy nationwide, and the 

San Luis Valley receives more direct solar radiation 

than any other part of the State (National Renewable 

Energy Laboratory 2007a, National Renewable Energy Laboratory 2007b). Interest in the development 

of the solar energy industry in the San Luis Valley 

continues to expand, especially since Colorado State 

legislation requires that 30 percent of large utilities’ 

electricity come from renewable sources by 2020 (Galbraith 2010). Prospective solar development in the local 

area is supported by Federal initiatives and funding 

from the U.S. Department of Energy (U.S. Department of Energy 2011, Jaffe 2011). The growth of the 

solar industry in the local area, however, is dependent 

on the ability of solar producers to obtain power purchase agreements from the Public Service Company 

of Colorado and may also be dependent on the future 

provision of transmission lines out of the valley (Colorado Department of Local Affairs 2011). Other nonrenewable (oil and gas) and renewable (wind) forms 

of energy development occur to a lesser extent in the 

SLVCA than many western States (USFWS 2010a).

SLVCA 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 time frame, more than 232,000 

acres of land have been protected, 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 the NRCS cannot handle the 

demand, either for time or funding (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 approximately 

530,000 acres to protect the remaining expanses of 

wildlife habitat in the SLVCA. This would 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, fee-title acquisition may be used by 

the Service to protect wetlands such as the Alamosa 

Marshes on the valley floor of the SLVCA. 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 appropriate conservation easements. The SLVCA will 

focus on the protection of wetland habitat types and 

associated uplands on private land within the valley 

floor through acquisition of conservation easements 

from willing sellers (USFWS 2010a). 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. 

Within the SLVCA, the Service proposes to purchase 

conservation easements to protect up to 500,000 acres 

of significant wildlife habitat to maintain wildlife populations, plant communities, and ecosystem processes 

in perpetuity (USFWS 2010a).

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 maintain ownership of 

their property, but transfer some of their ownership 

rights to the conservation entity. The most common 
Chapter 3 — Affected Environment 33

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 additional 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, 

and may include restrictions to ensure maintenance 

of historic water use patterns that benefit wildlife. 

Protecting critical water sources on private land will 

be a key objective within the SLVCA, and easement 

agreements may include restrictions on the sale or 

diversion of water from the land. 

Wetland habitat is common in the SLVCA on private lands in areas where ranchers irrigate and use 

habitat for native hay meadows and pastureland for 

livestock. Protection of wetland habitat types will 

ensure proper drying and flooding cycles while maintaining historic water use patterns in wetland basins 

that are beneficial to wildlife. 

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. Water laws 

are sensitive to 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 would 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. 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. 

Fee-title Purchases

Within the SLVCA, the Service proposes to 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. 

The primary fee-title acquisition component of the 

SLVCA is expansion of the Alamosa National Wildlife 

Refuge western boundary to include wetlands identified during the 1874, 1875, and 1877 Wheeler expedition as the Alamosa Marshes (U.S. Army Corps of 

Engineers 1878). The acquisition area includes the 

confluences of Alamosa River, Rock Creek, and La 

Jara Creek with the Rio Grande. The area still provides one of the largest intact wetland complexes in 

the San Luis Valley. That said, the acquisition of feetitle will be considered only in circumstances where 

the Service’s conservation objectives could not be met 

with conservation easements.

WATER LAW

Colorado

Colorado is divided into seven water divisions determined by 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.

Water rights in Colorado are subject to the prior 

appropriation doctrine; 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 demonstrate that there is intent to use the water, construct the diversion works, put the water to 

beneficial use, and establish a priority date. In Colorado, every water right must be adjudicated through 

the Water Court. There are now legal avenues to use 

water for beneficial use without a diversion, such as 

instream flows.

If there is not enough water to satisfy all water 

right holders in a particular stream, the State may 

shut off junior rights as necessary to ensure that senior water right holders receive their full appropriation. The Rio Grande basin in Colorado is considered 

over-appropriated. 

Ground water in Colorado is designated as either 

tributary or non-tributary. Tributary ground water is 

water contained in aquifers that have a direct hydraulic connection to surface water. The unconfined aquifer in the San Luis Valley is tributary ground water. 

Tributary ground water is treated administratively 

the same as a surface water diversion. The confined 

aquifer in the San Luis Valley is also considered tributary, though the hydraulic connection to the surface 

water system is poorly understood.

Water rights in Colorado can be transferred from 

one entity to another, but a change application must 
34 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

be filed and approved by the State Engineer and the 

Water Court. The amount available for transfer is 

limited to the consumptive use portion 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, as long as that water right has 

been severed from the land by an approved application through the State engineer and the Water Court.

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 (CWCB) 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 1973, Colorado clarified the CWCB’s authority to acquire existing, decreed senior water rights on 

a voluntary basis from willing owners for instream 

flow uses. New appropriations are new, junior water 

rights claimed by the CWCB to preserve the natural 

environment. New appropriations are considered by 

the CWCB each year and are filed annually with the 

Water Court for adjudication. New appropriations are 

generally limited to the minimum amount necessary 

to fulfill the purpose of the instream flow.

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 stockwatering (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 prior to 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 groundwater 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 undergroundwater 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, ensure that water is put to beneficial 

use, and maintain orderly development of the State’s 

water resources. There are currently 33 declared 

undergroundwater 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.

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 determined 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. 

Prior to 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 4 — Environmental 

Consequences

For alternatives A and B described in section 2, the 

following narrative documents the analysis of environmental effects expected to occur from implementing 

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. 

Additionally, surface water rights will continue to be 

subject to sale, altering hydrology that currently benefits many wildlife species. 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 off site or changes to how existing water rights are exercised.

ALTERNATIVE B (PROPOSED ACTION)

The establishment of the SLVCA will primarily 

maintain 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 due to prevention of subdivision and 

development. The SLVCA wouldn’t supersede existing mineral rights, and the program is therefore unlikely to affect mineral resources. 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 would diminish the wildlife value 

of such land. 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. There could be a 

net benefit to aquifer recharge if any of water rights 

acquired by the Service through this plan were adjudicated for instream flow (M. Estep, personal communication to M. Dixon, March 2012).

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 due to the ongoing efforts of 

agency partners and nongovernmental organizations, 

primarily through easements funded by private donations, the NRCS Wetland Reserve Program (WRP), 

and North American Wetlands Conservation Act 

(NAWCA) grants. These efforts are laudable and have 

conserved valuable habitat, particularly wetlands. 

However, they tend to under-represent non-wetland 

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 both NAWCA and 

WRP funds is much higher than historically available 

funding. Also, unlike a Land and Water Conservation 

Fund easement program, NAWCA requires matching 

funds, which may or may not be available. Therefore, 

there would likely continue to be erosion of habitat 

quality and a decrease in ecological resiliency due to 

land cover changes and associated fragmentation, introduction of exotic species, and construction of manmade structures that are incompatible with habitat 

use by some wildlife.

Outright habitat loss due to conversion of land to 

other uses is perhaps the most obvious threat to wildlife in most areas. In the SLVCA, this can take the 

form of conversion from natural to agricultural land 
36 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

cover, changes to irrigation regimes, and development 

of land for commercial or residential use. 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 (e.g. Hilty 

and Merenlender 2004), and for both breeding and 

stopover habitat for neotropical migratory songbirds 

in human-altered landscapes (Pennington, Hansel, and 

Blair 2008). Valley floor riparian areas provide nest 

habitat for the threatened southwestern willow flycatcher and the candidate 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 critical 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 is continued 

risk of development in previously contiguous riparian corridors, as well as in unprotected areas along 

the Sangre de Cristo Mountains in Costilla County, 

Colorado, and northern Taos County, New Mexico, 

which could endanger the future existence of populations and species under future climate conditions. The 

latter area is also habitat for the Canada lynx which 

is federally listed as threatened; development of that 

region, which could occur under alternative A, may 

isolate lynx in the southern Sangre de Cristos from 

those in the rest of the Rocky Mountains. 

ALTERNATIVE B (PROPOSED ACTION)

Establishment of the SLVCA 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 NWRs. While there 

are several 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 and/or breeding of Federal trust species, namely migratory birds 

and a handful of federally listed and candidate 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 and limited fee-title 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 Rio Grande, 

Conejos, and San Antonio Rivers, which are used by 

dozens of species of migratory songbirds. In the rivers and tributaries themselves, the use of easements 

could maintain conditions suitable for imperiled 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 wetlands in the midst of a highmountain 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 due to restrictions on the use 

of ground water, and water is likely to become an increasingly complex issue due to projected changes in 

runoff timing and uncertainty regarding future precipitation trends (Ray et al. 2008). This may encourage landowners who have quality wetlands to change 

how they exercise their water rights, to the detriment 

of species that use those wetlands. The easements 

may include language restricting changes to existing 

beneficial uses of water, meaning that willing sellers 

would agree to maintain practices that are of value 

to wildlife. For example, water could not be sold off 

of the property where water rights were being exercised when the easement was purchased unless the 

new use was deemed more beneficial to wildlife. This 

could be especially important for the sandhill crane, 

since the vast majority of its Rocky Mountain population uses the marshes and wet meadows of the San 

Luis Valley as a stopover during spring and fall migrations (Drewien and Bizeau 1974). Many of these 

wetlands would not exist at present without current 

land use practices.

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, southeast, and southwest 

portions of the valley. Much of this land is managed 

by the BLM. The largest areas of this vegetation in 
Chapter 4 — Environmental Consequences 37

the region are in Costilla County, Colorado, and these 

areas are almost entirely privately owned and not 

under conservation easements. Colorado Parks and 

Wildlife has identified that area as potential but unoccupied habitat for the Endangered Species Act candidate 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. Much of 

that area has been subdivided into small parcels, but 

little real development has occurred to date outside 

of small towns and cities. Given those factors, and 

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. It is unknown if there will be future attempts to 

reintroduce Gunnison sage-grouse to that area, but 

certainly it would be unlikely to happen if the existing habitat were altered.

As discussed under alternative A, there are large 

unprotected areas along the spine of the Sangre de 

Cristo Mountains in Costilla County, Colorado, extending into Taos County, New Mexico. Alternative 

B would allow the Service to use its acquisition authority to complement efforts by private land trusts 

to protect this important wildlife corridor and Canada 

lynx habitat. 

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 at present, 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 (PROPOSED ACTION)

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 

historical 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 will 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 (PROPOSED ACTION)

Social and Economic Impacts of Conservation Easements and Fee-title Acquisitions

Conservation easements and fee-title acquisitions 

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 and fee-title acquisitions, especially given that potential purchases may 

span decades. Due to future uncertainty surrounding 

such factors as the likelihood and timing of easements 

and acquisitions; the availability of Service funds to 

purchase lands; and population growth, land values, 

and agricultural commodity prices, the social and 

economic impacts of the easements and acquisitions 

cannot be quantified in this analysis. However, these 

impacts can be described qualitatively. This analysis 

discusses the following effects of conservation easements and fee-title acquisitions in the SLVCA:

■ conservation values in the region 

■ benefits to local communities

■ landowner compensation

■ effects to local government net revenue

Table 4, 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 and feetitle acquisitions can protect values associated with 

biodiversity and wildlife abundance, maintain 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 
38 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

as water purification, oxygen production, pollination, 

and waste breakdown, are also maintained for local 

residents through land preservation (Millennium 

Ecosystem Service Assessment 2005). The primary 

public benefit of Service conservation easements and 

fee-title acquisitions is enhanced and preserved wildlife habitat. As development stressors increase over 

time, many key off-refuge habitat areas may become 

less available due to conversion to non-wildlife habitat uses. Habitat preservation has been shown to 

stabilize and increase wildlife populations (Reynolds 

and others 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, over 

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. 

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 will vary 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) will generate 

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 isn’t to 

say there isn’t the chance for property values to increase substantially in rural areas as well (Vrooman 

1978, Phillips 2000, Crompton 2001, Thorsnes 2002). 

Conservation easement and fee-title purchases 

would also inject new money into the local economy. 

The sale of conservation easements and fee-title lands 

provides landowners with additional revenue. Some 

percentage of these funds 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 maintain the character of a 

region by protecting a traditional and historic way of 

life and the associated working landscape. Land with 

historic 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 historic value of their farm, 

ranch, and open space lands, and to pass this legacy 

on to their children and grandchildren. In addition to 

maintaining 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 will 

also spend their salaries in the local economy, thus 

supporting further local employment. 

Lands acquired through fee-title purchases would 

be managed by the Service. These lands would be 

converted from farmland to managed wetlands, which 

could result in a loss of agricultural production income 

for farmers and the elimination of farming-related purchases. However, maintenance of large intact expanses 

of wetland habitat through fee-title acquisition would 

require active management by the Service and the associated purchase of new equipment and supplies to 

manage these lands for wildlife habitat. Acquisition of 

additional fee-title lands and conservation easements 

may also result in increased recreation-related spending by visitors. 

Landowner Compensation. The Service proposes to buy 

conservation easements from willing sellers at fair 

market value. The fair market value of a conservation 

easement is determined 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 fair 

market 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 
Chapter 4 — Environmental Consequences 39

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. 

Conservation easements reduce the value of the 

encumbered property. A conservation easement will 

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 will 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 is more restrictive will have a greater 

effect on the value of the land than an easement that is 

less restrictive. The Service will purchase easements 

at their appraised fair market value; therefore, easements on lands with high development pressure will 

receive higher payments. 

For fee-title acquisitions, land owners would be 

compensated for the fair market value of the land. 

Land owners would forfeit all rights of ownership and 

turn the property over to the Service.

Effects on Local Government Net Revenue. The effects of 

conservation easements and fee-title acquisitions 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 and fee-title 

purchases 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 and limited fee-title purchases are expected to 

have 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 determine 

property tax liabilities; however, agricultural land is 

often assessed differently. In many States, the assessed 

value of agricultural land is determined 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, the majority of properties that will enter into 

conservation-easement agreements with the Service 

will be classified as agricultural land; thus, there will 

be little affect on the current property tax base for 

the nine-county area. Some of the lands in the SLVCA 

that will enter into easements are currently 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 permitted 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 will be dependent on the 

percent of easement acres that are purchased on fallow 

land (versus agricultural land), and on the reduction 

in the market value of the fallow lands. 

The purchase of fee-title lands at fair market value 

will 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 (RRS) 

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 the RRS Act, local counties receive an 

annual payment for lands that have been purchased 

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 fully 

fund the authorized level of payments. In fiscal year 

2010, actual RRS payments were 22 percent of authorized levels.

1 Special rules and statues apply in each State to determine 

if land in agricultural production and land in conservation 

easements is eligible to be assessed as agricultural land.
40 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

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 purchases the easement or land 

in fee-title. Fee-title purchases that result in the conversion of land out of agricultural production could reduce farmer income and expenditures on agricultural 

supplies purchased in the local area. However, these 

lands would be converted to wetland habitat, likely 

requiring habitat improvements and ongoing maintenance. These management activities would result in 

an increase in the amount of money spent on supplies 

purchased in the local area, as well as the potential for 

additional income for new Service employees. 

Effects on Local Government Costs. Land protection 

through conservation easements and fee-title acquisition 

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). 

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 due to 

development of areas outside of those protected by 

partner agencies and land trusts.

ALTERNATIVE B (PROPOSED ACTION)

No direct or indirect unavoidable adverse impacts 

to the environment would result from the selection 

of alternative B. An easement and limited fee-title 

program would not result in adverse impacts on the 

physical or biological environment. The selection of 

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 (PROPOSED ACTION)

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 would require an irreversible and 

irretrievable commitment of resources. The monitoring of easements would represent a minor increase 

in overall Service costs borne by the San Luis Valley 

NWR complex.

Short-Term versus LongTerm Productivity

Following is a discussion of short- and long-term effects.

ALTERNATIVE A (NO ACTION)

Continued efforts to conserve habitats would be ongoing through the efforts of Service activities like 
41

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 (PROPOSED ACTION)

The Service would be authorized to purchase 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 permit struggling operators to 

stay in business. This is particularly relevant given 

the changes to Colorado water law, which now require 

ground water users to purchase increasingly expensive surface water to minimize 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 currently 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 long-term 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 CFR 1508.7). The following describes the 

past, present, and reasonably foreseeable actions related to the proposed SLVCA. A discussion follows 

regarding the cumulative impacts of these actions in 

combination with the actions of alternatives A and B.

PAST, PRESENT, AND REASONABLY 

FORESEEABLE FUTURE ACTIONS

A number of private and public organizations have 

successfully implemented 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 the mitigation strategy in 

the draft San Luis Valley Habitat Conservation Plan 

planned for release in June 2012. The Service assumes 

that these land protection efforts will likely continue 

in the foreseeable future. 

The State of Colorado is implementing new laws 

regarding ground water augmentation, wherein landowners who use ground water for irrigation will have 

to purchase surface water rights to offset any adverse 

impacts on downstream users.

There is ongoing interest in the San Luis Valley 

for renewable energy development. There are smallscale commercial solar facilities currently deployed in 

the San Luis Valley, and the Department of Energy 

and the BLM are studying the impacts of additional 

facilities being developed on public land (BLM and 

DOE 2010). The BLM is currently reviewing the potential impacts of expanded geothermal leasing on 

public lands in the San Luis Valley (BLM 2012). The 

potential for increased energy production in the San 

Luis Valley has led to planning for the construction 

of a high-capacity transmission corridor through the 

valley, crossing the Sangre de Cristo Mountains at 

La Veta Pass. Planning for that power corridor has 

stalled; however, interest in building another corridor 

to promote energy reliability is ongoing. 

ALTERNATIVE A (NO ACTION)

Under this alternative, there would be no cumulative 

impacts on the environment since the Service would 

not undertake any additional land protection measures.

ALTERNATIVE B (PROPOSED ACTION)

The continuing land protection efforts of others, combined with the proposed action, may have non-linear, 

positive effects on wildlife populations. Since this alternative would focus on federally regulated species 

(i.e., 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. The Service seeks to coordinate its land protection efforts by 

promoting active communication with conservation 

partners on land protection opportunities as they arise 

so that the organization whose program is most appropriate can seek the acquisition of a particular land 

interest. The public and private conservation entities 

in the San Luis Valley have a long-standing 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 its mitigation targets in the San 

Luis Valley Habitat Conservation Plan. To this end, 

the Service would not undertake any acquisition of 
42 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

southwestern willow flycatcher habitats along the Rio 

Grande or Conejos Rivers 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 would include 

language restricting the sale of surface water rights 

from lands protected under this program. Because the 

easements would maintain 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 due to potentially limiting where such facilities could be sited.

Any impacts of the proposed action that are cumulative with the actions of others will largely be 

determined by 1) the number of landowners willing 

to enter into easement agreements with the Service 

and 2) the amount of funding available for acquisition 

of these easements.

Table 4. 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 will be preserved.

■ Same as for easements plus the conservation 

value of fee-title lands may be greater than easement lands because the Service would have the 

ability to increase conservation value through 

projects on the land.

Affects to local 

communities

■ The public will 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 historic ranching and farming 

landscapes will be preserved.

■ Same as for easements except traditional and 

historic 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

■ Land owners will be compensated for the fair 

market value of the easement.

■ Easements will reduce the fair market value of 

the encumbered property.

■ Landowners maintain the majority of use rights, 

but forfeit their right to develop or subdivide the 

land. Other possible restrictions include development of vertical structures, or diversion or sale 

of water rights.

■ Land owners will be compensated for the fair 

market value of the land.

■ Land owners 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 will 

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 are partially replaced 

with Refuge Revenue Sharing payments. 
Chapter 5. — Coordination and 

Environmental Review

This chapter describes how the Service coordinated 

with others and conducted environmental reviews of 

various aspects of the project proposal and analysis. 

Additional coordination and review would be needed 

to carry out the proposed action, if selected.

Agency Coordination

The Service has discussed the proposed establishment 

of the SLVCA with other Federal (USFS, National 

Park Service, BLM, NRCS), State of Colorado (Colorado Parks and Wildlife, Colorado Water Conservation 

Board), local county governments, and regional (Rio 

Grande Water Conservation District) agencies 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 participate 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. 

A number of 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, The Nature 

Conservancy, Rio Grande Headwaters Trust, Orient 

Land Trust, and Colorado Water Trust.

The Service coordinated internally in the development of this EA as well. Region 6 Refuge planning staff 

and San Luis Valley NWR Complex staff conducted 

the analysis and prepared this document, as well as 

the LPP. An intra-service Endangered Species Act 

section 7 consultation has been initiated and will be 

included as an appendix in the final LPP/EA. 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 A, List of Preparers and Reviewers).

Through the SLVCA, the Service hopes to help ensure the viability of wildlife habitats in an uncertain future.

© Joe Zinn

Contaminants and Hazardous 

Waste

The Service is required to invest in healthy lands. At 

a minimum, a Level I pre-acquisition site assessment 

by the USFWS Ecological Services – Colorado Field 

Office or New Mexico Field Office, as appropriate, 

would be required prior to acquisition.
44 Draft EA, San Luis Valley Conservation Area, Colorado and New Mexico

National Environmental 

Policy Act

The Service conducted this environmental 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

This 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 the natural and human environments. 

NEPA planning for this EA involved other government agencies and the public in the identification of 

issues and alternatives for the proposed project.

DISTRIBUTION AND AVAILABILITY

The Service distributed the draft EA (with the associated draft 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 

USFWS Region 6 office. The documents are also available electronically on the Refuge Planning website.

Project Web site: <http://www.fws.gov/

mountain-prairie/planning/lpp/index.html>

■ Project email: <slvrefugesplanning@fws.gov>

■ Planning Team Leader:

Dr. Mike Dixon

Attn: SLVCA EA

Division of Refuge Planning

U.S. Fish & Wildlife Service

P.O. Box 25486, Denver Federal Center

Denver, CO 80225

303/236-8132
Land Protection Plan

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), the U.S. Fish & Wildlife Service (Service) 

seeks to protect the remarkable ecological values 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. It encompasses the headwaters of the Rio Grande in southern Colorado and a 

small part of northern New Mexico. 

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 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 practices, primarily agriculture, 

have resulted in substantial changes to the hydrology 

of the San Luis Valley. Both reductions in surface flows 

due to diversions and lowering of the aquifer due to 

ground water extraction have resulted in a substantial loss of wetland habitat. Many of the remaining 

wetlands and their associated wildlife are maintained 

either accidentally as a product of agricultural water 

use or intentionally due to active manipulation such 

as irrigation with ground and surface water and the 

construction of dikes and ditches. The remaining wetlands and the low human population density associated 

with the largely agricultural economy of the valley 

have resulted in the San Luis Valley’s maintaining a 

significant portion of its biological value, particularly 

for migratory birds. However, rising agricultural 

costs, including those resulting from the recent requirement to augment surface flows to offset the impacts of ground water use, have led to an unsettled 

agricultural economy. The potential for farmers and 

ranchers to sell water rights from their lands or even 

convert current land use practices from agricultural 

to residential, industrial, or municipal uses will continue to grow and threaten the biological integrity of 

the San Luis Valley.

The Service proposes to create the SLVCA to conserve a network of vital wildlife habitat through voluntary conservation easements and a limited amount of 

fee-title acquisition. An overview of the project area 

is provided in Figure 1. The SLVCA acquisitions will 

focus on the protection of wetlands and associated 

uplands in the valley through the use of up to 500,000 

acres of conservation easements. Up to an additional 

30,000 acres of fee-title acquisition from willing sellers has been proposed where such acquisition would 

benefit the management and objectives of the three 

existing refuges, but this tool would only be used 

when Service objectives could not be accomplished 

with conservation easements.

The Service will phase in implementation of the 

overall project. We anticipate focusing first on the 

southern Sangre de Cristo mountains, with conservation on the valley floor to follow. During this comment 

period we want to hear from all interested parties and 

partners to ensure we understand and consider any 

concerns or comments about the acquisition of easements in these areas. A Habitat Conservation Plan 

for the southwestern willow flycatcher is currently 

in development by local governments and pertains 

to the valley floor. This and considerations about the 

actual easement language as it relates to water use 

and rights may take longer to resolve. These issues 

are less likely to be concerns in the southern Sangre 

de Cristo mountains. Therefore, we anticipate that, if 

the overall plan is approved, we will focus our initial 

implementation efforts there. 

Purpose of the SLVCA 

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 
46 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 1 . An overview of the general land cover of the SLVCA .
Chapter 1 — Introduction and Project Description 47

resilience of its diverse ecosystems. Acquisition and 

management of the SLVCA will focus on protecting 

riparian areas, wetlands, and key uplands that complement and connect existing protected areas and on 

maintaining and restoring the hydrology of the valley. 

This purpose is in alignment with, but does not supersede, the vision and statutory purposes of the three 

existing refuges within the San Luis Valley National 

Wildlife Refuge (NWR) Complex, as described below.

SAN LUIS VALLEY REFUGE COMPLEX

Vision:

The San Luis Valley 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 groundwater 

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 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, the refuges support 

and foster a collaborative spirit between their 

neighbors and partners to conserve the valley’s 

treasured resources.

ALAMOSA AND MONTE VISTA NWRS

Vision: 

Lands of the Alamosa and Monte Vista National 

Wildlife Refuge Complex and those owned by 

our partners will be managed in a way that 

contributes to the migratory bird resource 

in the San Luis Valley to the greatest extent 

possible to benefit people of the valley and the 

United States. Management will emphasize 

protection, enhancement, restoration, and, 

where appropriate, creation of a variety of 

wetland and riparian habitats in this waterrich yet arid mountain valley. Local residents and visitors will view refuge lands with 

a sense of pride and value their relationships 

and accomplishments with the U.S. Fish & 

Wildlife Service. 

Purpose:

Alamosa and Monte Vista NWRs 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.”

BACA NWR

Purpose:

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; 

and (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.

Issues Identified and 

Selected for Analysis

Please see discussion of Issues Identified and Selected 

for Analysis in Section 1.4 of the Environmental Assessment (EA) in this volume.

Public Review of and 

Comments on the Draft EA 

and LPP

To be populated following analysis of public comments 

on Draft EA/LPP

National Wildlife Refuge 

System and Authorities

Please see a discussion of the National Wildlife Refuge System and Authorities in Section 1.6 of the EA 

in this volume.
48 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Related Actions and 

Activities

Please see a discussion of Related Actions and Activities in Section 1.5 of the EA in this volume.

Habitat Protection and 

the Easement Acquisition 

Process

Habitat protection will occur through the purchase of 

conservation easements and limited fee-title acquisition, where necessary and appropriate to meet the 

Service’s conservation objectives. It is the Service’s 

long-established policy to acquire the minimum interest in land from willing sellers to achieve habitat 

protection goals.

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

Fish and Wildlife Act of 1956 .1 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 

additional funds to acquire interests in habitat and 

water through direct congressional appropriations, 

donations, and the Federal Land Trust Facilitation 

Act if Congress votes to reauthorize that act.

Conservation Easements and 

Other Acquisitions

An easement is a conservation tool that is commonly 

employed to conserve natural resources, and has been 

extensively employed in the SLVCA project area by 

other organizations. Easements involve the acquisition of certain rights to the property, such the right 

to subdivide or alter irrigation practices so as to drain 

wetlands, 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 land use practices, such as flood irrigation for haying and grazing, 

are consistent with wildlife resource protection, and 

the use of easements will help ensure a strong and 

vibrant rural lifestyle.

1 16 U.S.C. 742(a-j)

There may be circumstances in which management 

objectives cannot be achieved, such as small boundary 

adjustments to existing refuges or purchase of land 

appurtenant to a water right acquired for augmentation of refuge wells or to improve hydrology on existing refuge lands. In these cases, the Service would 

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

Please see a detailed description of the SLVCA area 

and the resources which could potentially be affected 

by its establishment in Chapter 3 of the EA in this 

volume.

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 historic 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.

DEVELOPMENT

Population growth, primarily exurban development, 

led to habitat fragmentation in the San Luis Valley 

in the latter part of the 20th and first part of the 21st 

centuries. The population of Colorado increased by 

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

Bureau 2010a). During a period of particularly rapid 

population growth in the San Luis Valley from 1990 to 

2003, the population of Mineral County increased by 

57.9 percent and Saguache County increased by 45.2 

percent. The absolute population numbers and densities are still low in those counties, but habitat loss 

and fragmentation due to residential and commercial 

development have been the greatest recent threat to 

trust species in the SLVCA. This rapid growth has 

tempered 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, that same downturn, 

coupled with depressed agricultural markets and pending expensive changes to Colorado’s ground water law, 

have forced many farmers and ranchers to subdivide 

their properties in order to continue operating. This 

proliferation of 5-, 10-, and 40-acre parcels that have 

appeared on the market is likely to exacerbate the 

ongoing impacts of exurban housing development on 

the habitats of the SLVCA.

Energy development is also an emerging threat to 

wildlife in the SLVCA. The impacts to 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. In fact, one of the largest photovoltaic 

plants in the United States is in the San Luis Valley. 

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 determined is unlikely to have 

significant impacts on the living resources of the valley (USFWS 2011). Reviews of hydrocarbon development impacts on ground nesting birds (Naugle et al. 

2011), ungulates (Hebblewhite 2011), and songbirds 

(Bayne and Dale 2011) have all found some evidence 

of mortality and/or behavior modification (such as 

avoidance of an area) associated with petroleum extraction. If commercially exploitable hydrocarbons 

are found during the planned exploration, petroleum 

extraction could be an additional threat to the living 

resources of the SLVCA.

FRAGMENTATION

Changes in land cover due to 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 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 

and wetland complexes that cross and connect existing protected areas. This action would protect wildlife movement corridors for both seasonal migration 

and colonization following large-scale disturbance or 

environmental change.
52 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

INVASIVE SPECIES

Increased human disturbance associated with development has also been shown to negatively affect adjoining habitat due to the invasion and establishment 

of invasive plant species. Invasive plants can have 

numerous detrimental effects; besides displacing native vegetation, they can alter nutrient cycling and 

soil chemistry, modify 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.

Figure 2 . Water is a critical resource for 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 .

© Julia Hall

WATER RESOURCES

In addition to the threats of the direct loss of habitat 

and fragmentation that accompany subdivision for 

exurban development, water rights associated with 

subdivided parcels are often sold with the property. 

This results in the loss of wetland habitat and wetland 

functions not only on the subdivided 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 populations with limited dispersal abilities may potentially 

become genetically and spatially isolated. Existing 

wetland habitats are shown in Figure 2.

Another threat to the sustainability of wetland and 

riparian habitat in the SLVCA is the chronic overuse of 

ground water. Due to legal and political circumstances, 

new ground water rules have been developed by the 

Colorado Division of Water Resources and will be applied to water users in the San Luis Valley starting 

in May 2012. Ground water usage, especially artesian 
Chapter 3 — Threats to and Status of Resources 53

well development, started during the early 1900s. The 

result has been construction of over 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 chronically exceeds recharge. 

The SLVCA would contribute to protection of wetland 

and riparian habitat from degradation by maintaining current water management practices and the associated benefits to the plant community and ground 

water hydrology.

CULTURAL RESOURCES

The proposed SLVCA is considered an important 

area for cultural resources due to 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 would 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 indicate that 

numerous 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). 

Wetland and riparian habitats, such as those found 

in the SLVCA, that are dependent on snow-melt from 

surrounding high mountain ecosystems would be 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 mid-century 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 due to 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 impact aquatic species, including 

reduction in overall stream flow, 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 due 

to 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 proposed SLVCA intends to maintain and restore habitat connectivity to promote a San Luis Valley ecosystem 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 historic 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 shown in Figure 3, protection of such corridors 

will preserve a network through which wildlife can 

recolonize or disperse following disturbance, making 

the ecosystem more resilient to short term change and 

increasing its adaptive capacity to long-term change.

Effects of the SLVCA on 

the Natural and Human 

Environment

For a thorough discussion of the effects of the proposed 

easement and limited fee-title acquisition program, 

see Section 4 of the EA in this volume.
54 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 3 . The SLVCA forms part of a broader network of public and private conservation lands, and by further 

networking these lands will contribute to the ability of the species and habitats of the Southern Rocky Mountains 

to adapt to climate change .
Chapter 4 — Project Implementation

Land Protection Options

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/or 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 The Nature Conservancy and Ducks 

Unlimited. 

CONSERVATION EASEMENTS AND LIMITED FEETITLE ACQUISITION (PROPOSED ACTION)

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 the proposed action, the Service seeks to protect up to 500,000 acres through conservation easements In the SLVCA. 

There are instances when the management and 

objectives of the existing three refuges in the San 

Luis Valley refuge complex may be simplified with 

small-scale acquisitions, but not with conservation 

easements. In such circumstances (e.g., boundary 

simplification or surface water rights acquisition for 

an existing refuge) the Service would consider up to 

a total of 30,000 acres of fee-title acquisition under 

the SLVCA. 

As discussed throughout this document, the SLVCA 

is a large, landscape-scale approach to conserving a 

diverse array of important habitats. Each of these 

habitats is home to different Federal trust species, 

and each comes with its own management complications related to land use, water use, and other issues. 

Therefore, if necessary, the SLVCA could be subdivided into multiple management units that could be 

managed together or independently, based on the 

judgment of the Service. Natural features to define 

such management units would be the Closed Basin, the 

watersheds draining the southern Sangre de Cristo 

Mountains south of Blanca Peak to their confluence 

with the Rio Grande, and the watersheds of the remaining tributaries and main stem of the Rio Grande. 

Conceptual boundaries for these units are identified in 

Figure 4; however, actual boundaries would be established based upon the needs of refuge management. 

Water use has an important influence on the persistence of habitat in the SLVCA, and the protection of 

that habitat may sometimes require easement stipulations regarding water use and sale of water rights, 

as detailed in Section 4.2.1. Crafting of the easement 

language may not be complete until after the SLVCA 

has been approved. In addition, the need to protect 

southwestern willow flycatcher habitat has led to a 

several-year effort by local governments to create the 

San Luis Valley Habitat Conservation Plan (HCP), 

a draft of which should be released mid-2012. The 

Service intends to defer its conservation partners in 

land protection as it relates to southwestern willow 

flycatcher habitat when necessary for them to meet 

their mitigation targets, but until the HCP is final, 

it would be difficult to ensure that the Service’s conservation efforts do not conflict with those of partner 

organizations. While these issues do not directly affect 

the prioritization strategy for the SLVCA (detailed 

in section 4.3), they may influence how the Service 

implements its conservation delivery. Therefore, the 

Service’s realty staff will focus initial efforts on the 

southern Sangre de Cristo Mountains and their drainages, where the aforementioned issues are not likely 

to be concerns.

Project Objectives and 

Actions

The Service seeks to establish the SLVCA in the San 

Luis Valley of central southern Colorado and northern New Mexico. The project area contains land in 

Hinsdale, Mineral, Rio Grande, Saguache, Conejos, 

Alamosa, and Costilla 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 
56 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 4 . Potential management units of the SLVCA, with the Closed Basin in tan, the southern Sangre de Cristo 

Mountain watersheds in green, and the remaining Rio Grande watershed in blue . .
Chapter 4 — Project Implementation 57

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 those 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 upon the area of privately held priority habitat in the San Luis Valley, the 

objective of the SLVCA project is to protect 500,000 

acres of uplands, wetlands, and riparian areas through 

easements and up to 30,000 acres through fee title.

EASEMENT TERMS AND REQUIREMENTS

The Service has successfully implemented easements 

in many projects, and existing language and guidelines 

would 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 would be 

provisions regarding water use. The types of wetland and associated upland habitats in which we are 

interested are largely supported by current water 

use practices. Easements would include a stipulation 

that changes in water use cannot adversely affect the 

quality of habitats that we seek to protect in the easements, and that water rights currently owned for use 

on a property under an easement could not be sold or 

transferred for use on other properties unless such a 

transfer was deemed beneficial to wildlife. 

The protection of riparian corridors is critically important in the SLVCA, particularly since much of this 

habitat has, or has the potential to have, the constituent elements of critical habitat for the southwestern 

willow flycatcher.1 While easement language would 

not prescribe specific management practices on these 

lands, landowners with suitable or potentially suitable 

riparian habitat would 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 prevent overgrazing 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 

1 FR 76(157), 50542-50629. Endangered and Threatened 

Wildlife and Plants; Designation of Revised Critical Habitat 

for Southwestern Willow Flycatcher. Agency: Fish and Wildlife 

Service. Action: Proposed Rule. August 15, 2011.

land interests. The Service’s environmental contaminants specialists from the Ecological Services offices 

in Colorado and New Mexico will be contacted to ensure that policies and guidelines are followed before 

acquisition of conservation easements or fee title.

ACQUISITION FUNDING

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. Monies in this fund are 

not derived from general taxes. While Land and Water Conservation Fund monies are intended for land 

and water conservation projects, funding is subject 

to annual appropriations by Congress for specific acquisition projects. If it is reauthorized by Congress, 

the Federal Land Trust Facilitation Act could also be 

used to fund specific acquisitions. This act is a law that 

allows the BLM to dispose of certain public lands in 

order to generate revenue for strategic conservation 

of habitat not currently in Federal trust.

The SLVCA project area includes several other 

government and nongovernmental organizations with 

overlapping conservation objectives. In the development of the SLVCA, we have prioritized land for 

acquisition by the Service, but our Land Protection 

Plan may also guide acquisitions for conservation by 

the NRCS (Wetland Reserve Program), The Nature 

Conservancy, Ducks Unlimited, and the Rio Grande 

Headwaters Land Trust, among others. 

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 of the SLVCA. Each of these focal species 

represents a group of species that are vulnerable to 

the same threat processes (Lambeck 1997). The species selected were Canada lynx, Rio Grande cutthroat 

trout, willow flycatcher, Lewis’ woodpecker, Wilson’s 

phalarope, American bittern, Gunnison sage-grouse, 

and sage thrasher. All of these are Federal trust species and/or have State or regional conservation status, 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.
58 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 5 . Southwestern Willow Flycatcher and Canada Lynx Habitat in the San Luis Valley Conservation Area .

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 upon literature reviews.

The southwestern willow flycatcher 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 willow and cottonwood riparian habitats necessary for 

willow flycatcher breeding in the San Luis Valley have 

been mapped in detail as part of the development of 

the draft San Luis Valley Habitat Conservation Plan 

for that species (ERO Resources, unpublished data). 

The data also capture the gallery 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 as 

core habitat in this prioritization scheme; as a second 

priority, a 200-meter buffer was used to minimize disturbance of the core habitat (Terry Ireland, USFWS 

Ecological Services, personal communication, February 2012). These priorities are illustrated in Figure 5. 

Canada lynx are federally listed as threatened and 

State listed in Colorado as endangered. Lynx range 

through the montane forests of the Rocky Mountains. 

They are resident in both 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, 

USFWS Ecological Services Colorado Field Office, 

personal communication, January 2012). Its 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, 
Chapter 4 — Project Implementation 59

Figure 6 . Rio Grande Cutthroat Trout Presence in the San Luis Valley Conservation Area .

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 dry-mesic spruce-fir forest 

and woodland) using 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 

earlier, coarser-scale historic 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. There 

is also a large expanse of vacant and/or unknown 

habitat identified in Costilla County. Current range 

polygons were selected to represent priority habitat 

for this species; the historic 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 NWR Complex, personal 

communication, January 2012) as well as habitat for 

many other species of migratory shorebirds. Because 
60 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 7 . Gunnison Sage Grouse Presence in the San Luis Valley Conservation Area .

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 

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, 

USFWS Division of Migratory Birds staff believe that 

most breeding likely occurs below 8,000 feet (S. Jones, 

USFWS 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 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). They are also found occasionally in wet meadows (Faanes 1981), particularly those 
Chapter 4 — Project Implementation 61

Figure 8 . Wilson’s Phalarope Habitat Prioritization in the San Luis Valley Conservation Area . .

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, Riffel et al. 2001) and prefer wetlands of greater than 3 hectares (Daub 1993, as cited in 

Dechant et al. 2004), that area was used as a threshold 

delimiting tall emergent wetlands of first and 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 a Service Region 6 bird of conservation concern as well as a Migratory Birds focal species. 

A range-wide conceptual model for the species was 

developed by the American Bird Conservancy based 

on Rocky Mountain Bird Observatory sampling data 

(Beason, Levad, and Leukering 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, the “fair” quality was selected for all land 

cover types. The model developers determined that 

Inter-Mountain Basins Big Sagebrush Shrubland, Inter-Mountain Basins Montane Sagebrush Steppe, and 

Colorado Plateau Mixed Low Sagebrush Shrubland 

would 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). Inter-Mountain Basins Mixed Salt Desert Scrub, 

Inter-Mountain Basins Greasewood Flat, and InterMountain Basins Semi-Desert Shrub Steppe support 
62 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

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 

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).

Figure 9 . American Bittern Habitat Prioritization in the San Luis Valley Conservation Area .

LANDSCAPE PRIORITIZATION

The species-specific maps are useful for determining 

where in the landscape the key habitats are for the 

identified focal species. However, they do not assist 

decision makers with determining which areas would 

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, Possingham, and 

Watts 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 (e.g., 

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 

or metrics of the human footprint.

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 
Chapter 4 — Project Implementation 63

and Smith 2011). Hexagons were 25 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 were excluded from the model as 

that status is not likely to change. 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 private land holding a 

particular conservation feature. The relative irreplaceability, or frequency with which individual hexagons 

were selected in the final solution for each of the 100 

models, is shown in Figure 11. 

Figure 10 . Sage Thrasher Habitat Prioritization in the San Luis Valley Conservation Area .

EVALUATION OF EASEMENT POTENTIAL

As described in section 1.5, acquisition of conservation 

easements is not a new tool for achieving conservation 

objectives within the SLVCA; the NRCS and many 

nongovernmental organizations hold tens of thousands 

of acres of easements in the valley. The Service does 

not currently hold easements in the project area; 

however, the Service has 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 priority species, as well as a consensus map that shows where conservation returns for 

Federal funds would 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 the Service’s decision making:

■ Overall conservation value – Is the property located, 

in whole or in part, in an area that was selected in 
64 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Figure 11 . Areas of overall conservation need . Relative irreplaceability indicates what proportion of models in 

which that particular conservation unit was selected .
Chapter 4 — Project Implementation 65

70 percent or more of the spatial conservation priority runs 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 section 4.3? 

■ 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) which justifies 

the property’s protection?

Nothing in these guidelines is intended to limit the 

appropriate exercising of discretion and professional 

judgment by realty specialists and refuge staff. Acquisition would comply with realty policy and potential acquisitions would 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.

Ecosystem Management and 

Landscape Conservation

To carry out the project, the Service will engage the 

Southern Rockies Landscape Conservation Cooperative, which is intended to deliver applied science to 

inform resource management decisions on landscapescale issues such as climate change. The Landscape 

Conservation Cooperative incorporates State, Federal, nonprofit, and university partners; this planning 

across agency jurisdictions and boundaries is necessary to ensure that conservation happens at the scale 

necessary to ensure that wildlife can adapt, migrate, 

and colonize new areas in response to environmental 

change. The Southern Rockies Landscape Conservation Cooperative is still in its formative stages, 

but the framework for collaborative conservation in 

its area of responsibility, including the SLVCA, has 

been developed.

INCORPORATING SCIENCE AND STRATEGIC 

HABITAT CONSERVATION IN THE SLVCA

The SLVCA encompasses 5.2 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 and/

or helps ensure the connectivity, resiliency, and longterm function of the ecosystems in the project area. 

Toward this end, 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/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), and because land protection 

undertaken to benefit these 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, USFWS Region 

6 Birds of Conservation Concern, and USFWS Migratory Birds 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 yellowbilled cuckoo, an Endangered Species Act candidate 

species. 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 pre-settlement 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 4.3. Decisions regarding 

how to rank competing parcels with limited available 

funds will follow the outline described in that section. 
66 Draft LPP, San Luis Valley Conservation Area, Colorado and New Mexico

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 and Conejos River 

were identified to maintain that level.2 As previously 

discussed, this habitat will be granted highest priority for land protection, and all easement opportunities within the priority lands for that species should 

be considered in the interest of providing redundancy 

to currently occupied habitat.

In the absence of specific population goals for the 

remaining focal species, no acreage numbers 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 

delivery are to protect 50 percent of existing priority habitat that currently exists on private lands for 

the other 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 delivery of easement and limited fee-title 

acquisition 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 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 and/or targeted research 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 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 in order to facilitate basic and 

applied research while addressing research gaps as 

they are identified.

Specifically, monitoring and research should include:

■ Developing, improving, and assessing landscape 

models for priority species. Emphasis will be placed 

on the highest priority species with the greatest 

2 FR 76(157): Endangered and Threatened Wildlife 

and Plants: Designation of Revised Critical Habitat for 

Southwestern Willow Flycatcher. pp. 50542-50629

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 

the nine 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 non-easement 

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, assumptions such as 

increased redundancy of occupied southwestern 

willow flycatcher habitat through protection of 

riparian vegetation will be evaluated.

■ Identifying appropriate population goals for priority 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 refine conservation delivery to ensure maximum effectiveness. 

■ Determining how changing environmental conditions may influence the effectiveness of this conservation design as increased evaporation, 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.

Socioeconomic 

Considerations

As discussed in detail in section 3.4 of the EA in this 

volume, 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 farmers with resources to invest that would allow 

them to continue operation. That money will largely 
Chapter 4 — Project Implementation 67

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 largely 

easement-based and therefore should not significantly 

impact 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 practices will also preserve the rural aesthetic 

which defines the region’s culture and the character 

of the San Luis Valley.

Public Involvement and 

Coordination

SCOPING

At the beginning of the planning process, the planning 

for the SLVCA was conducted in tandem with that for 

the San Luis Valley Refuge Complex CCP. 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 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 meeting was attended 

by over 300 members of the public.

Together, these meetings and subsequent feedback helped the Service to identify the questions and 

concerns of the public, as well as to refine the project 

boundary.

Distribution and Availability

Copies of the Land Protection Plan and Environmental 

Assessment were sent 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://mountain-prairie.fws.gov/planning/

lpp.htm>

U.S. Fish and Wildlife Service

San Luis Valley National Wildlife Refuge 

Complex

8249 Emperius Road

Alamosa, CO 81101

719/589 4021

Glossary

adaptive capacity – The ability of an ecosystem to 

maintain ecological function while adjusting to 

long-term changes in the environment, or shifting 

to a new normal (i.e., climate change, established 

invasive species)

anthropogenic – Caused by human activity

candidate species – A species of plant or animal for 

which the USFWS 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

comprehensive conservation plan – 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 appropriate, and are specified by contract 

between the land owner and the conservation entity

ecological resilience – The ability of an ecosystem to 

rebound from short-term changes to a landscape 

(i.e. wildfires, floods, pest outbreaks)

endangered species – A species of plant or animal 

that is in danger of extinction throughout all or a 

significant portion of its range

Endangered Species Act – A U.S. law passed by Congress in 1973 with the purpose of protecting and 

recovering imperiled species and the ecosystems 

on which they depend

environmental assessment – A National Environmental Policy Act (NEPA) compliance document 

which analyzes whether to prepare an environmental impact statement or a finding of no significant 

impact, facilitates compliance when no EIS is necessary, or facilitates preparation of an EIS when 

one is necessary.

focal species – Species which represent a group of 

species vulnerable to similar threats 

HUC – Hydrologic Unit Code, a hierarchical system 

created by USGS to identify locations regions by 

hydrology

land protection plan – A document required by USFWS policy prior to the establishment of new units 

of the National Wildlife Refuge System, or major 

expansions of existing units

landscape conservation cooperative – A public-private 

partnership intended to facilitate cross-political 

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

Region 6 – An administrative unit of the Service 

known as the Mountain-Prairie Region, which 

covers eight States: Colorado, Kansas, Montana, 

Nebraska, North Dakota, South Dakota, Utah, 

and Wyoming

Service – U.S. Fish & Wildlife Service

strategic habitat conservation – An iterative adaptive management framework designed to ensure 

that decision making and management within the 

Service is science-based. Consists of four stages: 

biological planning, conservation design, delivery of 

conservation action, and monitoring and research. 

threatened species – A species of plant or animal 

that is likely to become endangered in the foreseeable future

trust species – Species for which the Federal government has statutory responsibility, including 

threatened and endangered species, migratory 

birds, marine mammals, and interjurisdictional fish

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Appendix A

List of Preparers and Reviewers

Author’s Name Position Work Unit

Mike Blenden Project Leader USFWS, San Luis Valley NWR Complex, Alamosa, CO

Mike Dixon Land Protection Planner USFWS, Region 6, Planning Division, Lakewood, CO

Mark Ely Geographic Information Systems 

(GIS) Specialist

USFWS, Region 6, Planning Division, Lakewood, CO

Meg Estep Chief, Water Resources USFWS, Region 6, Water Resources Dvision, 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, 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, Realty USFWS, Region 6, Planning Division, Lakewood, CO

Laurie Shannon Conservation Planner USFWS, Region 6, Planning Division, Lakewood, CO

Appendix B

Species List of the San Luis Valley Conservation Area

Sources: Colorado Natural Diversity information Source (NDiS), SLV Refuge Complex Species List, USGS Nonindigenous Aquatic 

Species Database, NRCS Plants Database

* Non-native (Due to the number of plant species in the project area, introduced plants are not indicated)

Scientific Name English 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 SC

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

Archilochus alexandri Black-chinned Hummingbird
82 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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 ST

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

Aechmophorus clarkii Clark’s Grebe

Nucifraga columbiana Clark’s Nutcracker
Appendix B — Species List of the San Luis Valley Conservation Area 83

Scientific Name English Name Status

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 SC

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

Ardea alba Great Egret

Bubo virginianus Great Horned Owl

Geococcyx californianus Greater Roadrunner
84 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

Grus canadensis tabida Greater Sandhill Crane SC

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 SC

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 FE, SE

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 SC

Limnodromus scolopaceus Long-billed Dowitcher

Asio otus Long-eared Owl

Oporornis tolmiei MacGillivray’s Warbler

Eugenes fulgens Magnificent Hummingbird

Anas platyrhynchos Mallard

Limosa fedoa Marbled Godwit

Cistothorus palustris Marsh Wren
Appendix B — Species List of the San Luis Valley Conservation Area 85

Scientific Name English Name Status

Falco columbarius Merlin

Strix occidentalis lucida Mexican Spotted Owl FT, ST

Sialia currucoides Mountain Bluebird

Poecile gambeli Mountain Chickadee

Charadrius montanus Mountain Plover SC

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 SC

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

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
86 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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 SC

Tringa solitaria Solitary Sandpiper

Melospiza melodia Song Sparrow

Porzana carolina Sora

Empidonax traillii extimus Southwestern Willow Flycatcher FE, SE

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 87

Scientific Name English Name Status

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 FE, SE

Catoptrophorus semipalmatus Willet

Sphyrapicus thyroideus Williamson’s Sapsucker

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
88 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

Dendroica petechia Yellow Warbler

Coccyzus americanus Yellow-billed Cuckoo SC

Icteria virens Yellow-breasted Chat

Xanthocephalus xanthocephalus Yellow-headed Blackbird

Dendroica coronata Yellow-rumped Warbler

Amphibians

Bufo boreas boreas Boreal Toad SE

Rana catesbeiana Bullfrog*

Hyla arenicolor Canyon Treefrog

Bufo cognatus Great Plains Toad

Spea multiplicata New Mexico Spadefoot

Rana pipiens Northern Leopard Frog SC

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 FE, SE

Lepus californicus Black-tailed Jackrabbit

Lynx rufus Bobcat

Thomomys bottae Botta’s Pocket Gopher SC

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 89

Scientific Name English Name Status

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 Lynx FT, SE

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 SC

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 SC

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 SE

Spermophilus elegans Wyoming Ground Squirrel
90 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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 SC

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*

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 x 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*

Carassius auratus Goldfish*

Ctenopharyngodon idella Grass carp*

Xiphophorus hellerii Green swordtail*

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*
Appendix B — Species List of the San Luis Valley Conservation Area 91

Scientific Name English Name Status

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 SC

Oncorhynchus clarki virginalis Rio Grande cutthroat trout SC; Candidate

Catostomus plebeius Rio Grande sucker SE

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

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
92 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 93

Scientific Name English Name Status

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

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
94 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 95

Scientific Name English Name Status

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

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
96 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 97

Scientific Name English Name Status

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

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 field chickweed

Cerastium beeringianum Bering chickweed
98 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 99

Scientific Name English Name Status

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

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
100 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 101

Scientific Name English Name Status

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

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
102 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 103

Scientific Name English Name Status

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

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
104 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 105

Scientific Name English Name Status

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

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
106 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 107

Scientific Name English Name Status

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

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
108 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

Machaeranthera pinnatifida ssp. pinnatifida lacy tansyaster

Machaeranthera pinnatifida ssp. pinnatifida var. lacy tansyaster

pinnatifida

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 109

Scientific Name English Name Status

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

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
110 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 111

Scientific Name English Name Status

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

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 pointtip 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
112 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 113

Scientific Name English Name Status

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

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
114 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

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

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
Appendix B — Species List of the San Luis Valley Conservation Area 115

Scientific Name English Name Status

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

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
116 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

Sambucus racemosa red elderberry

Sambucus racemosa var. racemosa red elderberry

Sarcobatus vermiculatus greasewood

Saxifraga bronchialis yellowdot saxifrage

Saxifraga bronchialis ssp. austromontana matted saxifrage

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
Appendix B — Species List of the San Luis Valley Conservation Area 117

Scientific Name English Name Status

Senecio spartioides broom-like ragwort

Senecio spartioides var. multicapitatus broom-like ragwort

Senecio taraxacoides dandelion ragwort

Senecio triangularis arrowleaf ragwort

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
118 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English Name Status

Sphenopholis obtusata prairie wedgescale

Spiranthes romanzoffiana hooded lady’s tresses

Sporobolus airoides alkali sacaton

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. white panicle aster

hesperium

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
Appendix B — Species List of the San Luis Valley Conservation Area 119

Scientific Name English Name Status

Tetraneuris brandegeei Brandegee’s four-nerve daisy

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
120 Draft EA and LPP, San Luis Valley Conservation Area, Colorado and New Mexico

Scientific Name English 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