National Park Service

U.S. Department of the Interior

Natural Resource Stewardship and Science

Lava Beds National Monument

Natural Resource Condition Assessment

Natural Resource Report NPS/NRSS/WRD/NRR—2013/726
ON THE COVER

View from Schonchin Butte north of Tule Lake Basin

Courtesy of Lava Beds National Monument
Lava Beds National Monument

Natural Resource Condition Assessment

Natural Resource Report NPS/NRSS/WRD/NRR—2013/726

Paul R. Adamus

Water Resources Science Program

Oregon State University

Corvallis, OR

and

Adamus Resource Assessment, Inc.

Corvallis, OR

Dennis C. Odion, Gregory V. Jones, Lorin C. Groshong, Ryan Reid

Department of Environmental Studies

Southern Oregon University

Ashland, OR

Jean Krejca

Zara Environmental LLC

Manchaca, TX

This report was prepared under Task Agreement J8W07100032 (Cooperative Agreement

H8W07060001) between the National Park Service and Southern Oregon University.

November 2013

U.S. Department of the Interior

National Park Service

Natural Resource Stewardship and Science 

Fort Collins, Colorado
ii

The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, 

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screen readers, please email irma@nps.gov. 

Please cite this publication as:

Adamus, P. R., D. C. Odion, G. V. Jones, L. C. Groshong, R. Reid, and J. Krejca. 2013. Lava 

Beds National Monument Natural Resource Condition Assessment. Natural Resource Report

NPS/NRPC/WRD/NRR—xxx. National Park Service, Fort Collins, Colorado.
iii

Contents

Page

Figures............................................................................................................................................. v

Tables............................................................................................................................................ vii

Appendices..................................................................................................................................... ix

Executive Summary....................................................................................................................... xi

Acknowledgments........................................................................................................................ xiii

Prologue ....................................................................................................................................... xiii

1.0 NRCA Background................................................................................................................... 1

2.0 Introduction and Resource Setting............................................................................................ 5

3.0 Study Scoping, Design, and Implementation............................................................................ 9

3.1 Project Responsibilities ..................................................................................................... 9

3.2 Preliminary Scoping, Framework and Information Gathering.......................................... 9

4.0 Natural Resource Conditions.................................................................................................. 13

4.1 Changes in Climate and Microclimate (Ice, Groundwater)............................................. 13

4.1.1 Background.............................................................................................................. 13

4.1.2 Regional Context ..................................................................................................... 14

4.1.3 Issue Description...................................................................................................... 14

4.1.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 17

4.2 Changes in Cave Geologic Features................................................................................ 23

4.2.1 Background.............................................................................................................. 23

4.2.2 Regional Context ..................................................................................................... 29

4.2.3 Issues Description .................................................................................................... 30

4.2.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 30

4.3 Changes in Cave-dependent Species............................................................................... 32

4.3.1 Background.............................................................................................................. 32

4.3.2 Regional Context ..................................................................................................... 33

4.3.3 Issue Description...................................................................................................... 34

4.3.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 36
iv

4.4. Changes in Vegetation.................................................................................................... 42

4.4.1 Background.............................................................................................................. 42

4.4.2 Regional Context ..................................................................................................... 48

4.4.3 Issues Description .................................................................................................... 48

4.4.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 61

4.5 Changes in Aboveground Wildlife .................................................................................. 74

4.5.1 Background.............................................................................................................. 74

4.5.2 Regional Context ..................................................................................................... 74

4.5.3 Issues Description .................................................................................................... 74

4.5.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 76

4.6 Changes in Air Quality .................................................................................................... 88

4.6.1 Background.............................................................................................................. 88

4.6.2 Regional Context ..................................................................................................... 88

4.6.3 Issue Description...................................................................................................... 89

4.6.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 89

4.7 Changes in the Natural Quality of the Park Experience .................................................. 92

4.7.1 Background.............................................................................................................. 92

4.7.2 Regional Context ..................................................................................................... 92

4.7.3 Issue Description...................................................................................................... 92

4.7.4 Indicators and Criteria to Evaluate Condition and Trends....................................... 92

5.0 Discussion............................................................................................................................... 99

6.0 Literature Cited ..................................................................................................................... 103
v

Figures

Page

Figure 1. Location map for Lava Beds National Monument. .................................................................... 6

Figure 2. Base map for Lava Beds National Monument............................................................................ 7

Figure 3. Locations of major visitor-accessible caves at Lava Beds National Monument........................ 8

Figure 4. Analysis units used for this report. ........................................................................................... 12

Figure 5. Ice next to breakdown in Big Painted Cave. ............................................................................ 24

Figure 6. Pillar in Valentine Cave............................................................................................................ 25

Figure 7. Contraction cracks in Catacombs Cave. ................................................................................... 25

Figure 8. Lavacicles in Valentine Cave. .................................................................................................. 26

Figure 9. Benches in Valentine Cave....................................................................................................... 27

Figure 10. Balcony in Caldwell Ice Cave. ............................................................................................... 28

Figure 11. Example of cave coral. ........................................................................................................... 29

Figure 12. Winter hibernacula counts of Corynorhinus townsendii at 12 caves (coded to 

protect roost site information) from 1998 to 2010. (From Krejca et al. 2010.)........................................ 39

Figure 13. Log transformed winter hibernacula counts of Corynorhinus townsendii at 12 

caves (coded to protect roost site information) from 1998 to 2010. (From Krejca et al. 2010.).............. 40

Figure 14. Human influences on the structure, function, and composition of ecosystems...................... 43

Figure 15. General vegetation map of Lava Beds National Monument. The map is 

reproduced from the 2010 Draft General Management Plan and Assessment (Map 15). ........................ 45

Figure 16 a-d. Fire occurrence by decade in major vegetation types at Lava Beds. Vegetation 

is from 1970s mapping by Erhard (1979). Some vegetation would have differed at the time 

fire occurred than when the vegetation was mapped................................................................................ 59

Figure 17a. Conceptual model of general relationships between fire frequency, as measured 

by the fire rotation, and the abundance of cheatgrass, sagebrush-steppe, and woodlands at 

lower elevations of the monument............................................................................................................ 62

Figure 17b. Conceptual model of general relationships between fire frequency, as measured 

by the fire rotation, and the abundance of cheatgrass, sagebrush-steppe, and woodlands at 

middle and upper elevations of Lava Beds. .............................................................................................. 62

Figure 18. Location of cheatgrass in vegetation mapping plots (2009-2011) at Lava Beds 

National Monument. Cheatgrass occurred in every plot sampled (n=169). ............................................. 64

Figure 19. Locations of invasive plants documented at Lava Beds National Monument in 

169 vegetation mapping plots. .................................................................................................................. 66
vi

Figures (continued)

Page

Figure 20. Locations of invasive plant species recorded in FY 2011 Invasive Species Early 

Detection monitoring by the Klamath Network. The circle size denotes the size of the 

infestation.................................................................................................................................................. 68

Figure 21. Conceptual model of an invasive species early detection program and the 

feedbacks with management (From Odion et al. 2010)............................................................................ 69

Figure 22. Boundaries of the Tulelake Christmas Bird Count circle, relative to Lava Beds 

National Monument. ................................................................................................................................. 83

Figure 23. Visibility (in deciview units) from the monument, 1990 to 2010. (From 

IMPROVE web site: http://views.cira.colostate.edu/web) ....................................................................... 94

Figure 24. Total visits in 11 monitored visitor use caves during 1992-2008........................................... 97
vii

Tables

Page

Table 1. The range of projected changes to the climate (including temperature and 

precipitation) and ecology (dominant vegetation types, fire regime) of the Klamath Basin 

from three global climate models and a vegetation model ....................................................................... 15

Table 2. Ice trends as of 2012 in the monument’s monitored caves, adapted from Kern and 

Thomas (2012).......................................................................................................................................... 22

Table 3. Bat species with special conservation designations documented at Lava Beds 

National Monument. ................................................................................................................................. 34

Table 4. Prioritized invasive species list for monument-wide monitoring at Lava Beds 

National Monument. ................................................................................................................................. 52

Table 5. Equilibrium species in Lava Beds National Monument and status of which species 

will be monitored in the backcountry, and which will not be, for the reason given................................. 53

Table 6. Fire rotations in major vegetation types at Lava Beds for different time periods 

since 1910. ................................................................................................................................................ 60

Table 7. Vegetation indicators and the ecological conditions for which they apply. .............................. 61

Table 8. Summary of prioritized invasive species early-detection monitoring at Lava Beds 

NM. ........................................................................................................................................................... 67

Table 9. Rare plants listed by the California Native Plant Society (CNPS) from Lava Beds 

National Monument or the immediate vicinity (from Smith 2009).......................................................... 73

Table 10. Trends in selected wintering and resident songbirds and raptors in the Tulelake 

Christmas Bird Count, 1987-2011. ........................................................................................................... 80

Table 11. Summary of reasonably foreseeable vegetation-altering actions on public land in 

and adjacent to the Modoc National Forest .............................................................................................. 87

Table 12. Road density by geographic unit within Lava Beds National Monument. .............................. 88

Table 13. Summary of ratings for indicators of condition and trend used in this analysis of 

Lava Beds National Monument .............................................................................................................. 100

ix

Appendices 

Page

Appendix A. Climate of Lava Beds National Monument: supporting data and maps ........................... A-1

Appendix B. Physical Characteristics of Lava Beds National Monument: supporting data and 

maps........................................................................................................................................................ B-1

Appendix C. Vegetation and Fire Characteristics of Lava Beds National Monument: 

supporting data and maps........................................................................................................................ C-1

Appendix D. Vertebrate Species Records From the Lava Beds Wildlife Observations 

Database.................................................................................................................................................. D-1

xi

Executive Summary

To characterize the condition and trends in priority natural resources in Lava Beds National Monument, 

we compiled existing data and information. This report and the spatial datasets provided with it is

intended to inform and support park managers and scientists in developing recommendations for

improving or maintaining natural resource conditions in the park. It also can assist park resource

managers in meeting the reporting requirements of the Government Performance Results Act and Office

of Management and Budget.

In attempts to describe the current condition and trends for each of the park’s natural resources of 

concern, we followed generally the Environmental Protection Agency’s “Framework for Assessing and

Reporting on Ecological Condition” (Young and Sanzone 2002). Specifically, we first identified seven

natural resource themes considered by this park’s managers and scientists to be most important. They

are:

• Changes in Climate and Microclimate (including ice and groundwater)

• Changes in Cave Geologic Features

• Changes in Cave-dependent Species

• Changes in Vegetation

• Changes in Aboveground Wildlife

• Changes in Air Quality

• Changes in Natural Quality of the Park Experience

We identified 21 indicators to evaluate these seven resource concerns. For each indicator we then

attempted to define reference conditions to which we could compare present conditions. Making that

comparison, we described the condition of each indicator as “Good,” “Somewhat Concerning,” 

“Significant Concern,” or “Indeterminate.” We described the indicator’s trend as “Improving,” 

“Somewhat Concerning,” “Significant Concern,” or “Indeterminate.” In each instance where we applied

these terms, we also described (as high, moderate, or low) the certainty associated with our estimate. 

Where reference conditions that were the basis for our comparisons lacked quantitative standards, we

based the assessment on qualitative descriptions of least-altered resource conditions derived from

historical accounts, scientific literature, and professional opinion. 

Applying the 21 indicators, we determined that the condition of four indicators is of Significant Concern

in this park. Two -- the spread of cheatgrass and the decline of sagebrush cover -- are interrelated. The

reduced frequency of fire in some parts of the park has created conditions that are at the extreme end of

the natural age distribution for the park’s vegetation types. This can restrict the park’s ability to

effectively support the region’s wildlife and plant diversity. In addition, increasing threats from other 

invasive plants and the complete loss of persistent ice from three caves (and decline of ice in many 

others) are considered Significant Concerns.

The condition and/or trend of ten indicators is Somewhat Concerning: 

• Damage to cave geologic features

• Increasing cover of juniper
xii

• Decreasing cover of bunchgrasses

• Loss of diversity of native terrestrial wildlife species

• Impaired connectivity and extent of important terrestrial habitats

• High ozone concentrations

• Diminished visibility

• Long-term changes in aboveground temperature and precipitation

Managers have limited capacity to influence the condition of the last three. However, NPS has had some 

success working with policy makers and regulators to enforce stricter standards when park data 

indicated air quality problems resulting from local sources.

Information sufficient to estimate trends was lacking for 14 of the 21 indicators, and none were

considered to have a high degree of certainty. Information sufficient to estimate present condition was 

lacking for 5 of the 21 indicators. 
xiii

Acknowledgments

For their steadfast interest in this assessment and helpful suggestions, we thank Daniel Sarr (NPS,

Klamath Network I&M Program’s Supervisory Ecologist) and Marsha Davis (NPS Pacific West

Regional Office). For their useful input during preparation of this assessment, from Lava Beds National 

Monument we thank David Larson, Nancy Nordensten, Shane Fryer, Shawn Thomas, and Jason 

Mateljak. Overall guidance was provided by the NPS Project Managers—initially David Larson from

Lava Beds, succeeded by Mac Brock from Crater Lake National Park.

Prologue

Publisher’s Note: This report is part of an ongoing series of natural resource condition assessments in 

national park units. As a point of clarification, this document does not follow the standard report outline 

that the National Park Service (NPS) has established for the series. However, the condition assessment 

methodologies and reporting details found in chapter 4—the “core section” of the report—do conform to 

NPS guidelines.

1

1.0 NRCA Background

What is the current condition of natural resources in our nation’s national parks? How has that condition 

changed in recent years? What might be the actual and potential causes of current and future change? 

This report, prepared under a National Park Service (NPS) agreement with Southern Oregon University

(SOU), attempts to address these questions as they pertain to Lava Beds National Monument.

Addressing these questions is essential to the mission of the NPS. Thus, the NPS in 2003 initiated

overview assessments of each of 270-plus parks which NPS deemed to have significant natural

resources and related values. Those assessments, termed “Natural Resource Condition Assessments”

(NRCAs), focus on compiling and interpreting existing data, and are intended to complement Inventory

and Monitoring (I&M) programs and other efforts that feature the collection of new data. Both programs

complement and help support each park’s development of a Resource Stewardship Strategy (RSS)1,

which focuses instead on management targets and provides guidance on how to respond to and manage

threats. NRCAs rely significantly on review and syntheses of existing data and maps, as contrasted with

the NPS Vital Signs Program which mainly features the collection of new field data.

NRCAs evaluate current conditions for a subset of natural resources and resource indicators. NRCAs

also report on trends in resource condition (when possible), identify critical data gaps, and characterize a

general level of confidence for study findings. The resources and indicators emphasized in a given

project depend on the park’s resource setting, status of resource stewardship planning and science in

identifying high-priority indicators, and availability of data and expertise to assess current conditions for

a variety of potential study resources and indicators.

NRCAs represent a relatively new approach to assessing and reporting on park resource conditions.

They are meant to complement—not replace—traditional issue- and threat-based resource assessments.

As distinguishing characteristics, NRCAs:

• are multi-disciplinary in scope;

2

• employ hierarchical indicator frameworks;3

• identify or develop reference conditions/values for comparison against current conditions;4

 

1 formerly called a Resource Management Plan (RMP).

2 The breadth of natural resources and number/type of indicators evaluated will vary by park. 

3 Frameworks help guide a multi-disciplinary selection of indicators and subsequent “roll up” and reporting of data 

for measures  conditions for indicators  condition summaries by broader topics and park areas 

4 NRCAs must consider ecologically-based reference conditions, must also consider applicable legal and 

regulatory standards, and can consider other management-specified condition objectives or targets; each study 

indicator can be evaluated against one or more types of logical reference conditions. Reference values can be 

expressed in qualitative to quantitative terms, as a single value or range of values; they represent desirable 

resource conditions or, alternatively, condition states that we wish to avoid or that require a follow-on response 

(e.g., ecological thresholds or management “triggers”).
2

• emphasize spatial evaluation of conditions and GIS (map) products;5

• summarize key findings by park areas; and6

• follow national NRCA guidelines and standards for study design and reporting products.

Although the primary objective of NRCAs is to report on current conditions relative to logical forms of

reference conditions and values, NRCAs also report on trends, when appropriate (i.e., when the

underlying data and methods support such reporting), as well as influences on resource conditions.

These influences may include past activities or conditions that provide a helpful context for

understanding current conditions, and/or present-day threats and stressors that are best interpreted at

park, watershed, or landscape scales (though NRCAs are not required to report on condition status for

land areas and natural resources beyond park boundaries). Intensive cause-and-effect analyses of threats

and stressors, and development of detailed treatment options, are outside the scope of NRCAs.

Due to their modest funding, relatively quick timeframe for completion, and reliance on existing data

and information, NRCAs are not intended to be exhaustive. Their methodology typically involves an

informal synthesis of scientific data and information from multiple and diverse sources. Level of rigor

and statistical repeatability will vary by resource or indicator, reflecting differences in existing data and

knowledge bases across the varied study components.

The credibility of NRCA results is derived from the data, methods, and reference values used in the

project work, which are designed to be appropriate for the stated purpose of the project, as well as

adequately documented. NRCAs can yield new insights about current park resource conditions but, in

many cases, their greatest value may be the development of useful documentation regarding known or

suspected resource conditions within parks. Reporting products can help park managers as they think

about near-term workload priorities, frame data and study needs for important park resources, and

communicate messages about current park resource conditions to various audiences. A successful

NRCA delivers science-based information that is both credible and has practical uses for a variety of

park decision-making, planning, and partnership activities.

However, it is important to note that NRCAs do not establish management targets for study indicators.

That process must occur through park planning and management activities. What an NRCA can do is

deliver science-based information that will assist park managers in their ongoing, long-term efforts to

describe and quantify a park’s desired resource conditions and management targets. In the near term,

NRCA findings assist strategic park resource planning7 and help parks to report on government

 

5 As possible and appropriate, NRCAs describe condition gradients or differences across a park for important 

natural resources and study indicators through a set of GIS coverages and map products. 

6 In addition to reporting on indicator-level conditions, NRCAs attempt to take a bigger picture (more holistic) view 

and summarize overall findings and provide suggestions to managers on an area-by-area basis: 1) by park 

ecosystem/habitat types or watersheds, and 2) for other park areas as requested.

7 An NRCA can be useful during the development of a park’s Resource Stewardship Strategy (RSS) and can also 

be tailored to act as a post-RSS project.
3

accountability measures.8 In addition, although in-depth analysis of the effects of climate change on

park natural resources is outside the scope of NRCAs, the condition analyses and data sets developed for

NRCAs will be useful for park-level climate-change studies and planning efforts. For more information

on the NRCA program, visit http://nature.nps.gov/water/nrca/index.cfm

 

8 While accountability reporting measures are subject to change, the spatial and reference-based condition data 

provided by NRCAs will be useful for most forms of “resource condition status” reporting as may be required by 

the NPS, the Department of the Interior, or the Office of Management and Budget. 

5

2.0 Introduction and Resource Setting

Lava Beds National Monument was established in 1925 by the presidential proclamation of President

Calvin Coolidge. The unique landscape was set aside to protect and interpret volcanic and natural

features of scientific interest, and evidence of prehistoric and historic human settlement, use, and

conflict.

The 46,560 acre monument is located in northeastern California, approximately 155 miles northeast of

Redding and 50 miles southeast of Klamath Falls, Oregon. Ninety-four percent of the monument lies

within Siskiyou County in the 2nd Congressional District. The remaining six percent is in Modoc

County in the 4th Congressional District. The monument boundary is bordered by Modoc National

Forest, Klamath National Forest, the Lower Klamath Basin National Wildlife Refuges (Tulelake

Refuge), Bureau of Reclamation land, and Bureau of Land Management land, as well as private lands. 

The monument contains some of the most extensive and least impacted lava tube caves in the western

United States (Figures 1-3). Regulated public access is allowed to about 22 of the monument’s 700+ 

caves, and these are easily accessible from trails, roads, picnic areas, and off-trail areas. Many of the 

other caves are in remote, isolated areas and are not well known to the general public. The majority of

the monument’s primary visitor sites contain non-renewable geologic features. These include Fleener

Chimneys, Black Crater, Petroglyph Point, Schonchin Butte, and Captain Jack’s Stronghold. The 

monument is also distinctive because it occurs at the junction of the Sierra-Nevada, Cascade, and Great

Basin geologic provinces. The monument contains a range of Great Basin vegetation communities,

including ponderosa pine forest, mountain mahogany/juniper community, and Great Basin

sagebrush/bunchgrass steppe community.

The monument also incorporates a portion of the Medicine Lake shield volcano, a 900-square-mile

highland created by various types of volcanic eruptions. Over the last half-million years, eruptions on

the Medicine Lake shield volcano have created a rugged wilderness landscape dotted with diverse

volcanic features. These volcanic features, and the resultant habitats formed across the monument,

encompass the significant natural resources the monument protects and manages:

• the largest concentration of lava tube caves in the contiguous U.S., along with unique environments

and cave-dependent species,

• outstanding, diverse, abundant, and well preserved lava flows, cinder cones, spatter cones, maar

volcanoes, and other volcanic features associated with the Medicine Lake shield volcano,

• wilderness in the unique volcanic landscape of the Great Basin and Cascade ecosystems, and

• native plant and animal species, their habitats, and the processes (such as fire) representative of the

transition zone for Great Basin and Cascade ecosystems.

The effects of environmental degradation outside the monument (e.g., air pollution) undoubtedly extend 

into the monument. Conversely, significant benefits from the monument extend beyond the monument’s 

boundaries. These include being a likely source area and refugium for local and regional populations of 

terrestrial animals, recharging groundwater that is important to high-volume irrigation wells just outside 

the monument’s borders (Martin 2007), and helping support the local tourism economy. The monument 

supports a number of wildlife species that are rare or declining regionally or locally, as well as over 280 

plant species and a relatively intact bunchgrass community.
6

Figure 1. Location map for Lava Beds National Monument.
7

Figure 2. Base map for Lava Beds National Monument.
8

Figure 3. Locations of major visitor-accessible caves at Lava Beds National Monument.
9

3.0 Study Scoping, Design, and Implementation

3.1 Project Responsibilities

Co-investigators for this project were Dr. Greg Jones, climatologist, Southern Oregon University, and

Dr. Paul Adamus, ecologist, Oregon State University. Dr. Jones administered the agreement and

analyzed climatological data (section 2.1). Sections 2.2 (Cave Geologic Features) and 2.3 (Cavedependent Species) were prepared mainly by Jean Krejca and other staff at Zara Environmental, LLC. 

Section 2.4 of this report (Vegetation) was written by Dennis Odion, Southern Oregon University. The 

rest of this report was written by Paul Adamus, who also served as overall editor. Spatial data were

compiled and analyzed by Ryan Reid and Lorin Groshong (GIS specialists, Southern Oregon

University) with substantial input from other members of the project team.

3.2 Preliminary Scoping, Framework and Information Gathering

This assessment is one of three NRCAs prepared under a single agreement with Southern Oregon 

University. The others pertain to Lassen Volcanic National Park (LAVO) and Crater Lake National Park 

(CRLA). The assessments began in October 2010 with a scoping workshop that included the SOU study 

team, most members of the NPS Project Oversight Committee9, and other scientists from the three parks 

being assessed. Held at the monument headquarters near Tulelake, California, the session began with a 

background description of the NRCA process presented by Marsha Davis from the NPS Pacific West 

Regional Office, followed by presentations by the project co-principal investigators and others, and a 

group discussion focusing on project frameworks and strategy. Information gathering then began as the 

study team spent the remainder of the day conferring with several of the natural resource scientists at 

Lava Beds. 

Natural resource issues at the monument had recently been prioritized by the monument’s staff, using a

structured input process, and that was a great help in focusing our efforts. In no particular order, the 19 

“focal themes” that were ranked highest (3 on a scale of 0 to 3) from a list of 56 themes considered

potentially applicable to the three Klamath Network parks that are the subject of this SOU agreement

were:

• Cave processes

• Cave features

• Cave entrance ecology

• Cave flora and fauna

• Bats

• Ice monitoring

• Geologic resources and features

 

9 From the monument: David Larson (formerly, Chief of Resources and NRCA Project Manager), Jason Mateljak 

(Resource Management Specialist), Shane Fryer (Physical Scientist). From CRLA: Mac Brock (Chief of 

Resources), Jeff Runde (Resource Management Specialist and Data Manager), Chris Wayne (GIS Specialist). 

From Lassen: Louise Johnson (formerly, Chief of Resources), Nancy Nordensten (formerly, Resource 

Management Specialist; Biologist), Janet Coles (Plant Ecologist). From Pacific West Regional Office: Marsha 

Davis (Geologist).
10

• Areas of focal species

• Habitat for focal species

• Fire regimes

• Fire suppression and fuels management

• Invasive species (plants)

• Solitude and silence

• Recreation

• Road and trail development

• Social trails

• Wilderness

• Dark night sky

• Global warming

In addition, indicators of natural resource condition had recently been identified through the Klamath

Network’s Vital Signs planning process. Some of that information was used to target indicators pertinent

to our NRCA effort.

Subsequently, all relevant documents from the parks were identified. This task was made easier by the

Klamath Network having recently completed a “data mining” report. That report was accompanied by a

bibliographic database of nearly all published and unpublished documents and maps for these parks, up

to about 2007. We augmented that using online search engines (Web of Science, Google Scholar) to

identify newer publications from the three parks, as well as relevant documents pertaining to the regions

surrounding these parks, searching with phrases such as Southern Cascades. We obtained complete

digital copies (PDFs) of many publications that reported relevant research results from the monument 

and surrounding region. We then indexed all digital documents in an Excel spreadsheet so they could be

sorted by topic and year. The database and all the digital documents, as well as spatial data layers, were

placed on a server computer at SOU that was accessible to the project team throughout this project.

We reviewed and considered several frameworks for organizing our NRCA effort. We decided to follow

generally the Environmental Protection Agency’s “Framework for Assessing and Reporting on

Ecological Condition” (Young and Sanzone 2002). Specifically, for each priority resource we identified 

multiple indicators of resource condition and defined reference conditions that could be used as a basis

for assessing these. An ecological indicator is any measurable attribute that provides insights into the

state of the environment and provides information beyond its own measurement (Noon 2003). Indicators

are usually surrogates for properties or system responses that are too difficult or costly to measure

directly (Leibowitz et al. 1999). Indicators differ from estimators in that functional relationships

between the indicator and the various ecological attributes are generally unknown (McKelvey and

Pearson 2001). Not all indicators are equally informative—one of the key challenges of an NRCA is to

select those attributes whose values (or trends) provide insights into ecological integrity at the scale of

the ecosystem.

In developing the list of indicators and specific measures, we considered some basic criteria for useful

ecological indicators as provided by Harwell et al. (1999). “Useful indicators need to be understandable

to multiple audiences, including scientists, policy makers, managers and the public; they need to show

status and/or condition over time; and there should be a clear, transparent scientific basis for the

assigned condition.” Indicators need to be based on probability distributions whenever possible to
11

capture the natural range of variation in conditions, and we have attempted to do that whenever possible. 

We evaluated the indicators we chose by assigning qualitative descriptors as follows:

Condition: Good, Somewhat Concerning, Significant Concern, or Indeterminate.

Trend: Improving, Somewhat Concerning, Significant Concern, or Indeterminate.

Certainty: High, Medium, or Low.

We defined these terms in the context of each specific resource or issue we evaluated. Most indicators

were assessed at the park scale, although connections to regional conditions were noted where supported

by previously published analyses. The maps prepared for this assessment potentially reveal differences

in resources at a finer scale, i.e., within the monument. Some of the spatial data were also compiled in

tables organized by the monument’s four major habitat types. Those types (“analysis units”) are shown 

in Figure 4.
12

Figure 4. Analysis units used for this report.
13

4.0 Natural Resource Conditions

According to monument staff, the greatest concerns regarding the natural resources at Lava Beds are 

currently: 

1. Changes in climate and microclimate

2. Changes in cave geologic features

3. Changes in cave-dependent species 

4. Changes in vegetation

5. Changes in aboveground wildlife

6. Changes in air quality

7. Changes in the natural quality of the park experience

Each of these concerns is described in this chapter using the following structure:

• Background

• Regional Context

• Issue Description

• Indicators and Criteria to Evaluate Condition and Trends:

Criteria

Condition and Trends

Assessment Confidence and Data Gaps

Higher priority was assigned to data that were collected (a) for indicators that are anticipated to be most 

sensitive to the priority resource issues, and/or (b) according to a standardized protocol, and/or (c) from 

multiple years (the farther apart the better), and/or (d) from many locations within the monument.

4.1 Changes in Climate and Microclimate (Ice, Groundwater)

4.1.1 Background

Climate change has the potential to affect all of the monument’s ecosystems, including the microclimate 

within its key feature, the lava caves. Microclimate refers primarily to the temperature and humidity of 

air, and its variation at a more localized spatial scale. 

Temperature partly determines which species occur in a park, as well as controlling many biological, 

chemical, and physical processes such as ice formation in caves. Precipitation also influences species 

that are present, as well as geologic erosion, groundwater levels, and humidity within caves, pollutant 

transport, and fire risk. 

Long-term precipitation and aboveground temperature averages for this park are shown in Appendix A. 

Located in the desert interior, the monument receives far less precipitation than the other Klamath 

Network parks. Most precipitation occurs in winter, with a secondary peak in late spring. Snowfall 

accumulations are usually apparent only in January and February. Within the monument, climate 

gradients on the land surface are gradual, with the coolest temperatures at higher elevations, and the

warmest at lower elevations. Minimum temperatures in most months are lower in the northern part of

the monument. The monument is located on the edge of the Tule Lake Basin, and that feature acts as a
14

cold air pool, drawing cooler air from surrounding mountains. The southern part of the monument is

slightly wetter than the rest because of the rain-intercepting effect of the Medicine Lake shield volcano. 

4.1.2 Regional Context

Normally, areas closer to the ocean are at somewhat less risk of major temperature shifts because of the 

ocean’s moderating effect on temperature. They also tend to receive more precipitation. Although this 

monument is relatively close to the Pacific Ocean (125 miles), its higher elevation and physiographic 

setting (“rain shadow” effect to the west) reduce the ocean’s climate-moderating effects, thus making 

the monument’s ecosystems more vulnerable to climate change.

4.1.3 Issue Description

4.1.3.1 Historical Climate Change

In western North America generally, during the twentieth century the winter and spring temperatures

increased (Mote et al. 2005). The rate of change varied by location, but generally a warming of 1°C

occurred from 1916 to 2003 (Hamlet et al. 2007). The rate of temperature increase from 1947 to 2003

was roughly double that averaged for the entire period from 1916 to 2003. This was largely attributable

to the fact that much of the observed warming occurred from 1975 to 2003. Regionally averaged spring

and summer temperatures for 1987 to 2003 were 0.87°C higher than those for 1970 to 1986, and spring

and summer temperatures for 1987 to 2003 were the warmest since the beginning of the record in 1895

(Westerling et al. 2006). The largest warming trends have occurred in January-March (Hamlet and

Lettenmaier 2007).

4.1.3.2 Future Climate Change

For the western U.S., simulations of future climate indicate that average temperatures will likely

increase in both winter and summer (Giorgi et al. 2001). The average warming rate in the Pacific

Northwest during the next ~50 years is expected to be in the range of 0.1-0.6°C per decade, with a best

estimate of 0.3°C per decade. For comparison, observed warming in the second half of the twentieth 

century was approximately 0.2°C per decade (Mote et al. 2008). Less certainty is associated with

projected changes in regional precipitation than those for temperature. Climate projections for the

Klamath Region as a whole (Barr et al. 2010) are shown in Table 1.
15

Table 1. The range of projected changes to the climate (including temperature and precipitation) and ecology 

(dominant vegetation types, fire regime) of the Klamath Basin from three global climate models and a vegetation 

model. Baseline conditions are based on data from 1961-1990. Snowpack projections are based on results from 

supporting studies (Hayhoe et al. 2004; Goodstein and Matson 2004). 

Projected Average Annual and Seasonal Temperature Increase from Baseline

2035 - 2045 2075 - 2085

Annual

June – August

December – February

+2.1 to +3.6° F (+1.1 to +2.0° C)

+2.2 to +4.8° F (+1.2 to 2.7° C)

+1.7 to +3.6° F (+1.0 to 2.0° C)

+4.6 to +7.2° F (+2.5 to +4.6° C)

+5.8 to +11.8° F (+3.2 to +6.6° C)

+3.8 to +6.5° F (+2.1 to +3.6° C)

Projected Average Annual and Seasonal Change in Precipitation from Baseline

Annual

June – August

December - February

-0.27 to +0.07 inch (-9 to +2 %)

-0.16 to +0.11 inch (-15 to -23 %)

+0.06 to +0.57 inch (+1 to +10 %)

-0.33 to +0.74 inch (-11 to +24 %)

-0.25 to +1.00 inch (-37 to -3 %)

-0.28 to +1.59 inch (-5 to +27 %)

Projected Percent Change in Area Burned on Annual Basis Compared to Baseline

Area Burned +13 to 18% +11 to 22%

Projected Change in Vegetation Growing Conditions from Baseline

Vegetation Growing

Conditions

Complete loss of subalpine.

Partial loss of maritime conifer (Douglasfir and spruce).

Expansion of oak and madrone.

Partial to complete loss of maritime conifer

Expansion of oak and madrone.

Possible replacement of sagebrush and

juniper with grasslands.

Projected Change in Snowpack from Baseline

Snowpack Loss of 37 to 65% Loss of 73 to 90%

Estimates from Hayhoe et al. (2004) are from the Sierra Nevada range and estimates from Goodstein and Matson

(2004) are for Oregon and Washington, including the Klamath region.

4.1.3.3 Ice Formation in Lava Tube Caves

Ice forms in the lava tube caves when precipitation seeps into the ground, infiltrates downward into the 

caves, and accumulates and freezes there. If the water did not freeze in the caves, it would likely freeze 

at some lower stratum or infiltrate all the way to the regional water table, at 4010 ft elevation above 

mean sea level (msl) (Martin 2007). Although this is several hundred feet below the lowest cave floor 

elevation of many of the caves (Hyatt 1965), the floors of some of the caves in the northern part of the 

monument are at a lower elevation, and could be within less than 100 feet of the groundwater if the 

water table roughly parallels the land (or cave bottom) surface. This is a potential concern because a 

drop in groundwater levels in the park and in some surrounding areas has been reported (see below).

Erosion or loss of perennial ice formations might also occur as a result of changing climatic conditions

and could be accelerated by cave visitation. Airflow and changing ventilation patterns due to rock fall

from seismic activity could have significantly affected the ice in Merrill Cave, for example (Fuhrmann
16

2007). Also, visitors throwing rocks at ice edges and/or otherwise dislodging ice has been observed

there.

In general, factors that may influence ice formation and melting include anything that could change

airflow patterns such as any structures at cave entrances or even within caves, including gates,

platforms, stairs, or dirt mounds. Structures over caves may fill tiny entrances (not necessarily passable

by humans) that provide airflow. Clearly climate change could impact ice levels via changes in rainfall,

humidity, wind, or temperature. Heat from human visitation could increase the temperature inside a cave

and lead to melting temperatures for ice. Human contact with ice such as walking on it or running a hand

along it would also erode an ice deposit and cause wear and degradation.

4.1.3.4 Groundwater Levels

The monument is in the Tule Lake Groundwater Subbasin, as defined by the California Department of 

Water Resources. The headquarters area is the only area of the monument with a public water supply 

system. A water supply well located there supplies water for the visitor center, campground, park 

offices, and employee housing.

The USGS has monitored groundwater levels at least quarterly since 2001 at four locations within the

monument as part of a regional study. The USGS reports that the water levels in wells in the monument 

declined an average of 1.5 to 2 feet per year from late 2001 to spring 2005. Plots of data covering the 

period since 2005 area were available only for the monument’s Petroglyph Point monitoring well, and 

appear to show a declining trend since at least 2003. 

Outside the monument, there was a decline of 5-10 feet in the water table in the Panhandle and Copic 

Bay areas adjacent to the northeast corner of the monument from 2001 to 2005 (Gannett et al. 2007). 

However, many of the shallow wells in the Tule Lake Groundwater Subbasin outside of the monument 

experienced no water level decline during this same period, perhaps because they alone were benefitting 

from infiltrated irrigation water. The water table declines coincided with a dramatic increase in 

groundwater pumping in the Tule Lake Groundwater Subbasin outside of the monument (Martin 2007). 

The increased pumping was initiated largely due to a negotiated agreement between various agencies 

and stakeholders to substitute groundwater for surface water for irrigation in the basin and to use 

groundwater to augment surface water supplies to meet the needs of endangered fish species in waters 

outside the monument. Acute water table declines have been measured in the Subbasin in direct 

response to pumping for a lateral distance of hundreds to thousands of feet from active well pumps, but 

water table recovery generally occurs soon after pumps are turned off (Gannett et al. 2010). In this 

Subbasin, pumping from wells within a few miles of groundwater-discharge features, such as springs 

and drains, can affect those features within weeks or months of the onset of pumping, and the impacts 

can be fully manifest in several years (Gannett et al. 2012).

Water table declines measured by the USGS began the same year (2002) as a severe local drought 

began, which lasted through that year and was followed by drier than normal conditions that persisted 

into the early part of 2005 (Gannett et al. 2010). Long-term groundwater-level data from near the town 

of Tulelake showed the rate of the year-to-year decline observed during the drought was about twice that 

observed in the most recent previous drought, which occurred from the late 1980s through mid-1990s. 

The total decline between 2001 and 2004 exceeded 15 feet in some parts of the region surrounding the 

monument, and is larger than can be attributed to drought alone. The year-to-year decline was 

accompanied by amplified seasonal declines. Some increase occurred thereafter; see Gannett et al. 
17

(2010) for details. How long (if ever) it will take water levels to fully return to previous levels after wet 

climate conditions return and pumping stress is reduced is not known (Gannett et al. 2010). 

Although the USGS studies did not focus specifically on groundwater quality, some degradation of 

groundwater quality has occurred in the northern part of the monument, partly as a result of infiltration 

of salt-laden surface water from the Tule Lake Sump, the large water body northeast of the monument 

(Martin 2007). 

The monument is within a region of geothermal heat flow that is great enough to be of economic interest

for its potential to generate power. The Glass Mountain Known Geothermal Resource Area (KGRA) is 

located adjacent to the monument to the south. The KGRA allows competitive lease sales for geothermal

exploration. In the past there has been exploratory drilling for geothermal resources between the

Medicine Lake area and the monument’s southern boundary. These activities are unlikely to have 

directly impacted the monument’s groundwater levels because of their distance from the monument as 

well as the depth of the wells (much deeper than the monument’s caves) and the intervening geologic 

conditions (Martin 2007). However, future geothermal developments could impact the monument’s cave 

microclimates indirectly if they intercept shallow groundwater for cooling or other purposes.

4.1.4 Indicators and Criteria to Evaluate Condition and Trends

Although little or nothing can be done within the monument to address the problem of global or regional 

climate change, improved knowledge of current conditions and anticipated changes can help resource

planning efforts. Indicators that would inform this issue might include the condition and trends of the

following:

1. Aboveground precipitation and temperature

2. Cave microclimate

3. Cave ice formation and persistence

Each of these is now discussed.

4.1.4.1 Aboveground Precipitation and Temperature

Aboveground precipitation and temperature influence the microclimate and ice formation within the 

monument’s caves, as well as influencing strongly the monument’s terrestrial wildlife and vegetation. 

Locations of various types of weather instruments in or near the monument were mapped and described

in Davey et al. (2007) and Daly et al. (2009). Those with the longest consistent record are Lava Beds

NM (4770 ft elevation, in the center of the monument) and Tulelake (4035 ft, about 12 miles north of

the monument). The Lava Beds NM station is not entirely representative of the monument because most 

of the monument is at somewhat lower elevation. Most of the monument would be expected to have 

lower minimum temperatures due to closer connection with the Tule Lake Basin cold air pool. 

Criteria

A rating of “Good” would describe a condition where the amount and seasonal timing of precipitation is

at or above the average historical condition in all parts of the monument. “Somewhat Concerning”

conditions would be defined as an amount and timing that are less than necessary to sustain the

monument’s ecosystems—directly or indirectly—close to their present state. “Significant Concern”

conditions would be an amount and timing that are less than necessary to sustain the monument’s

ecosystems close to their historical (pre-settlement) long-term condition.
18

Condition and Trends

Condition: Indeterminate.

Trends: Somewhat Concerning – Medium Certainty. 

Trends in precipitation and temperature are somewhat concerning. We analyzed and identified the 

following statistically significant trends based on data from monument headquarters (1959 through 

2011) except where noted as Tulelake (1932-2011 data):

• warmer annual maximum temperatures

• warmer minimum high temperatures

• fewer days per year with extremely low maximum temperatures

• more days per year with extremely hot temperatures

• fewer days per year with extremely low minimum temperatures (Tulelake)

• fewer days where the maximum temperature was below freezing

• longer warm spells

• shorter cold spells (Tulelake)

• greater diurnal temperature range

• longer wet periods (Tulelake)

In addition, Daly et al. (2009) computed trends in temperature and precipitation at monument 

headquarters for each month, and for two periods: 1895–2007 and 1971–2007 (see Appendix A). For

annual precipitation, they found very little overall trend over the century. Precipitation was relatively

high in the early part of the century, then fell to a minimum in the 1920s and ‘30s. Precipitation varied

little from year to year until the 1970s, when a cyclical pattern began, with maxima in the mid-1980s

and late 1990s. They found temperatures have been rising significantly, and more strongly, in the last

30 years than in the past century. Specifically, and over the 1895–2007 period, the average maximum

temperatures show significant increases in January and September and decreases in November. Over the

1971–2007 period, maximum temperatures increased significantly in March, July, and annually. Trends 

were generally similar between the headquarters readings and those from Tulelake, though levels of 

statistical significance often differed.

Assessment Confidence and Data Gaps

Medium Certainty. Consistently-measured surface temperature and precipitation data covering a 

relatively long period are available from only one location within the monument (headquarters). If 

additional weather stations were established at higher and lower elevations within the monument and 

spaced well apart, they could yield data essential to understanding cave ice formation and processes 

important to the monument’s ecosystems.

4.1.4.2 Cave Microclimate

The microclimate within the monument’s caves may be influenced both by the land above and the 

groundwater below, though the relative contribution of these influences is unmeasured in the monument. 

Climate in caves is distinctly different from the aboveground climate, and its uniqueness is essential to 

supporting similarly unique assemblages of cave-dwelling animals and plants (see section 4.3 for more

on cave dependent species).

Although there is considerable variation among and within caves, humidity inside caves is often greater 

than on the land surface at equivalent temperatures. Direct precipitation, ultraviolet radiation, and strong 
19

winds are of course absent. Temperatures in caves are cooler in summer and warmer in winter relative to 

surface temperatures. Temperature and humidity vary much less than on the surface—diurnally, daily, 

and annually—and temporal variation is least in the most interior portions of caves. Despite being much 

more muted, cave temperatures follow seasonal and annual patterns that generally parallel those on the 

surface, with some lags. The similarity between a particular cave’s microclimate and land surface 

conditions is generally greater the closer the cave is to the land surface. With regard to their 

microclimate differences, caves in this park are classified as being deeper or shallower than 30 ft 

(Arnold 1993). 

Microclimate averages and variances change significantly according to distance into cave, depth below

the subsurface, and according to the presence of features such as constrictions, multiple entrances, low

spots in the passage that serve as cold traps, domes that serve as warm traps, or ice deposits. 

Microclimate in caves is typically measured in degrees of air temperature and percentage air humidity,

but can also include speed of airflow in a given size passage or volume of airflow that passes a point per

unit time, surface temperature of walls or ceilings, and water temperature. Air currents in caves are 

greater when there are large differences in air density in and out of the cave, and among caves that have 

multiple entrances on different levels. To a lesser extent, air currents within a cave may increase when 

outside conditions are windy or dry for long periods. In smaller, shallow caves, temperatures can be 

influenced by shade as determined by the north-south orientation of the entrance and perhaps by large 

differences in ground cover above the cave or near its entrance. Cave microclimates can be changed by 

natural events (e.g., rockfall blocking off internal or external passages) as well as by human activities 

such as building of structures in cave entrances, or by connecting or blocking internal or external 

passages or entrances. 

Criteria

Temperature and humidity levels in caves located outside the monument cannot validly be used as a 

basis for setting expectations for the monument’s caves because of differences in geology, morphology, 

and regional climate. There are no suitably analogous caves to define acceptable conditions, nor are 

there biological data that link cave flora and fauna to a particular humidity and temperature regime. 

Thus, “Good” condition would be represented by humidity and temperatures that are close to the

average historical condition in each of the monument’s caves. “Somewhat Concerning” and “Significant

Concern” conditions would be defined by the degree of deviation from those conditions. 

Condition and Trends

Condition: Indeterminate.

Trends: Indeterminate – Indeterminate Certainty.

Although humidity and temperature have been measured for varying lengths of time in some of the 

monument’s caves, valid comparisons between years using existing data are not possible because no 

network of caves has been monitored consistently for many years continuously. Also, the extent to 

which microclimate conditions and trends in one or a few caves can be extrapolated to others in the 

monument is unknown. Even within a single cave, the degree to which a temperature unit’s data are 

representative of conditions in that cave generally is unknown, and likely varies diurnally, by season, 

and by cave depth and morphology. Moreover, even if a good record existed of every cave’s temperature 

and humidity, the exact conditions needed to sustain a cave’s entire flora and fauna are unknown.
20

Assessment Confidence and Data Gaps

Low Certainty. The power to detect trends in microclimate increases with increasing numbers of

temperature loggers deployed and with increasing duration of monitoring. To have 80% power to detect

a 2% change in average annual temperature (of the middle zone of a cave), about 12 years of data might

be needed (Krejca et al. 2010). Data from thermal loggers are less reliable at the higher humidity levels 

(e.g. above 95%) that sometimes are present in some of the monument’s caves. Also, temperature and

humidity readings tend to ‘drift’ with time, necessitating frequent calibration and ‘resting’ of the meters

in a low humidity environment. Data loggers must be placed in exactly the same spot in a cave during all 

years (Krejca et al. 2010). 

4.1.4.3 Cave Ice Formation and Persistence

The monument has documented 700+ lava tube caves with over 30 miles of known passageways. Of 

these caves, an estimated 35 contain ice during most years. Ice occurs in many forms, including small 

pockets, stalactite/stalagmite forms, and large blocks that fill entire rooms. 

Caves with perennial ice have a distinctly different microclimate than those without. Ice maintains 

cooler summer temperatures and greater and less-variable cave humidity. Ice floors act as temperature

buffers, so when ice extent declines, air temperatures within a cave fluctuate over a broader range. 

Compared to other caves, the caves with perennial ice have microclimates that are even more different 

from surface conditions than are those of other lava tube caves. This might aid the persistence of some 

characteristic cave-dependent species that use these caves, although among the monument’s caves, the 

presence of bat hibernacula does not correlate with occurrence of perennial ice (Shawn Thomas, pers. 

comm.). Because there are no streams, ponds, springs, or wetlands in the entire monument, the ice 

deposits nearest the entrances of the caves are a localized source of water for a few wildlife species in 

this monument’s semiarid landscape. 

The exact mechanisms of ice formation within the monument’s caves are not well understood. However, 

several theories are described by Hyatt (1965) and summarized here. One theory is based on air 

displacement: the coldest winter air sinks into downward-sloping caves and displaces any warmer air 

that may be present in caves, and the cold air is trapped causing the persistence of cave ice with minimal 

summer air circulation. Another theory is based on active air circulation: as water freezes, heat is 

released and flows out of the cave entrance, and this circulation would freeze ice in winter and draw 

cold air into the cave. A third theory proposes that cave ice is the remainder from the glacial ages. For 

example, ice mineral stains on the walls of Merrill Cave (and other ice caves in the monument) indicate

that the lower passage was mostly filled by ice until some unknown recent time. The ice might have 

existed there since the last period of glacial activity in the region, 70,000 to 10,000 years ago, but this 

could not be determined with certainty. This theory of ice causation would apply only to caves with 

large bodies of permanent ice, as great mass and a tremendous potential for heat absorption would be 

required for ice to remain in a cave since the last glaciations in this area.

Criteria

For purposes of this assessment, “Good” conditions would be sustained ice levels at or greater than their 

current conditions in each cave in this monument, and within their natural range of annual variation. 

“Somewhat Concerning” and “Significant Concern” conditions would be defined by the degree of 

negative departure from those conditions. Ice levels in caves located outside the monument cannot 

validly be used as a basis for setting expectations for the monument’s caves because they are hundreds 

of miles away and differ geologically. 
21

Condition and Trends

Condition: Indeterminate.

Trends: Somewhat Concerning – High Certainty (and for at least 3 caves: Significant Concern). 

Attempts have been made to measure ice levels systematically in several caves, beginning with eight

caves in 1990 and 12-17 since 2005. In the remaining ice caves, informal visual inspections are 

conducted annually. 

Ice levels in some caves appear to vary considerably from year to year without a well-defined trend, but 

in others the trend has been negative. In 1999 the ice in Merrill Ice Cave, which contained one of the

larger ice resources in the monument, began to melt with the formation of a hole in the center of the ice

floor. By 2001, nearly all the ice had disappeared. Analysis of ice level data revealed that from the

1960s until about 1998, ice levels in Merrill Cave increased, but around 1998 the ice decreased

drastically and disappeared. However, limited evidence suggests that the ice deposit in Merrill Cave has

fluctuated dramatically over several thousand years (Fuhrmann (2007). Available data on ice trends 

within the past 20 years are summarized in Table 2; the described trends have not been tested for 

statistical significance.
22

Table 2. Ice trends as of 2012 in the monument’s monitored caves, adapted from Kern and Thomas (2012).

Cave Name

Monitored 

Since: Trend in Cave Ice Level Depth

Skull 1991 no change or possibly a slight increase since 1995

Merrill 1991 increase until ~1998, then large decrease, NONE by 2006

M-470 1991 no change, then decrease 1999-2004, then NONE

C-270 1991 decrease since 2000

M-475 1991 decrease 1999-2005, then NONE

M-310 1991 decrease, then increase since 2005

M-340 1991 decrease

Crystal 1982 decrease

L-800 1991 increase, then decrease since 2003

Heppe 2005 increase, then decrease since 2007

U-200 2005 mostly stable

B-020 2009 mostly stable

L-215 2009 mostly stable

Ice caves not shown in Table 2 are nonetheless observed informally (not measured) by park staff. Those 

observations suggest that declines have occurred in most of those caves, with three nearing a total loss

(Shawn Thomas, pers. comm.). As expected due to cooler temperatures with depth, ice disappears last in 

the deepest parts of most ice caves.

Another aspect of cave ice is its phenology, specifically, the time of year at which a given ice formation 

reaches its annual maximum and minimum. With the exception of Skull and possibly M-470, the 

minimum typically occurs around November. In Merrill Cave, until all its perennial ice disappeared, 

November had usually been the month of ice maximum rather than minimum (Kern and Thomas 2012). 

No correlation is apparent between the month of ice minimum or its interannual variability and the 

increasing or decreasing interannual trend in the ice. In a 2003-2004 study of Crystal Cave, the lag 

between surface temperature and cave temperature varied from 19 to 62 days, depending on depth 

within the cave. Visitation of caves is likely to have the greatest impact on cave temperatures (and 

indirectly, on ice resources) when visits are numerous and occur during winter.

Assessment Confidence and Data Gaps

Medium Certainty. Besides air temperature (which is influenced locally by elevation and aspect of a 

cave entrance, number of entrances, cave depth, and within-cave topography), the factors that influence 

annual ice extent in a particular cave might include immediate or time-lagged precipitation and seepage 

rates of surface and ground water (which are influenced locally by surficial geology, topography, and 

vegetation). These deserve further study to determine, for example, why some of the deepest caves do 
23

not retain perennial ice, whereas some shallower ones do. These differences are likely due to different 

regimes of temperature and moisture availability. Rain which occurs latter within the melting phase is 

often lost to groundwater, or may even diminish existing ice in caves. Because no well-defined aquifers 

are known to occur within the monument, the source, quantity and movement of groundwater in the 

monument, as possibly relates to cave microclimates and ice formation, requires further investigation. 

This need is especially important because limited evidence to date suggests that groundwater levels 

within the monument may also be decreasing (see section 4.1.3). 

Systematic monitoring of cave ice needs to be expanded to more ice caves. Too little time has passed to 

identify statistically significant trends in some of the monitored caves. Measuring ice in a standardized 

and meaningful way is challenging. Time series photographs provide a general picture and a limited 

archive of photos exists, but quantification of ice volume or depth from images is not possible. Thus, the 

vertical level of the ice from an established benchmark is typically what is monitored, although uneven

surfaces and irregularly shaped floors mean that the same magnitudes of decline among several caves 

are not equivalent. For this reason, in the plan for the Klamath Network’s Inventory and Monitoring

Program, Krejca et al. (2010) recommended also measuring the surface area of ice, referenced as well to 

the benchmark. 

4.2 Changes in Cave Geologic Features

4.2.1 Background

The lava tube caves are of course the natural feature most visitors come to the monument to see. This 

highlights the importance of understanding changes to the condition of these features. 

A number of cave geologic features are present. As described by Blacic (2006) they include the 

following. Breakdown consists of pieces of the lava tube wall or ceiling that have broken off and fallen 

to the floor during the lava’s cooling phase as contraction cracks form due to shrinkage of the inner 

linings of the tube (Figure 5). Occasionally a skylight forms when the entire thickness of a lava tube 

ceiling collapses, creating an opening to the surface. Tube in tube occurs when a lava stream flows 

through an existing tube and the outer surface of the flow forms an insulating crust within the existing 

tube, leaving behind a cast of a “cave within a cave.” A pillar is a column of hardened lava which forms 

when there is an obstacle in the path of the flow such as a tree or rock (Figure 6). Contraction cracks

form in the walls of lava tubes as the lining on the inside cools and shrinkage occurs (Figure 7). 

Dripstone is a coating over a cave wall where hot lava dripped down the wall. Pull outs consist of 

sections of wall where hot lava peeled away and exposed older linings of harder lava. Lavacicles, also 

called lava stalactites, are drip-shaped points of hardened lava on cave ceilings which form when lava 

drips off a hot molten ceiling or when lava splashes up from a flow below (Figure 8). A drip stalagmite

is a roughly conical pile of lava dripped from the ceiling. Benches occur when several flows of different 

heights move through the same lava tube and ledges of hardened lava are deposited along cave walls 

marking the top of prior flows (Figure 9). A balcony is a section of benches that spans the entire width 

of the cave leaving a passage below (Figure 10). 
24

Figure 5. Ice next to breakdown in Big Painted Cave.
25

Figure 6. Pillar in Valentine Cave.

Figure 7. Contraction cracks in Catacombs Cave.
26

Figure 8. Lavacicles in Valentine Cave.
27

Figure 9. Benches in Valentine Cave.
28

Figure 10. Balcony in Caldwell Ice Cave.

Secondary mineralization is deposited by percolating groundwater on cave roof and walls to form 

crystals that are usually white or yellowish. This process results in formations such as stalactites and 

stalagmites that are familiar from non-lava caves. Sometimes the crystals form in delicate and intricate 

shapes called cave coral (Figure 11). From a limited sampling of substances in the monument’s caves, 

the following minerals or compounds of natural origin were noted by Rogers and Rice (1992): calcite 

(very common), cristobalite (very common), opal-CT (very common), opal-A (moderately common), 

amberat (common), and uric acid (moderately common). The last two of these are of biological origin.
29

Figure 11. Example of cave coral.

4.2.2 Regional Context

The monument has the highest concentration of lava caves within the contiguous United States. Other 

significant lava caves or cave rich areas in the western contiguous U.S. include Lava River Cave in

Oregon's Newberry National Volcanic Monument (225 miles), Ape Cave in Washington (390 miles), 

and Craters of the Moon National Monument and Preserve in Idaho (450 miles). Oregon Caves National 

Monument, located just 100 miles northeast, contains a different type of cave (dissolution, comprised 

mainly of marble).
30

4.2.3 Issues Description

Geologic features within the caves face several threats, including surface wear from visitor traffic, 

sediment deposition, erosive chemical changes, and nearby seismic and volcanic activity. These are now 

described.

4.2.3.1 Surface Wear and Graffiti from Visitors

Accelerated erosion or loss of geologic features occurs as a result of visitor foot traffic. As people travel 

through cave passages, delicate formations that formed tens of thousands of years ago are broken off, 

cracked, or simply worn off from repeated foot/hand/knee placement. Outside of caves this type of wear 

happens naturally from wind, rain, and freeze/thaw erosion, but underground where temperatures are 

stable and lava tube surfaces are protected from erosion, these features are commonly intact. In caves, 

the traffic easily impacts a high percentage of the overall lava tube interior, and the features do not 

rebound with disuse, as may occur on the surface with footpaths, soil, and vegetation. This inadvertent 

wear and tear results in worn floors, broken formations, and sediment deposition (Tinsley 1992) and is 

unsightly. Graffiti from recent cave visitors also degrades cave features, obscuring natural formations 

that provide insight into geologic processes.

4.2.3.2 Sediment Deposition

Visitors inadvertently bring into the caves small amounts of soil attached to their shoes. When shed from 

thousands of boots over many years, the deposited sediment cumulatively can add significantly to what 

is present naturally. However, in other instances moist sediment that has existed for eons within a cave 

is transported outside by constant foot traffic. Foot traffic also compacts the sediments in cave floors 

that originally were more porous. Together with sediment deposition that fills in microtopographic 

variations in the cave floor, the microhabitat available for cave dwelling species can be degraded. 

4.2.3.3 Erosive Chemical Changes

Accelerated erosion or loss of geologic features might also occur gradually as a result of air pollution

(particularly sulfate) and groundwater pollution (e.g., from road runoff). Typically this type of pollution

acidifies water, causing chemical corrosion of cave surfaces, in addition to possibly creating an 

environment toxic to some cave species. Also, over the span of many future decades, climate change 

could result in more ambient carbon dioxide, and the acidifying conditions it causes are capable of 

accelerating chemical erosion of some cave features.

4.2.3.4 Nearby Volcanic and Seismic Activity

Although the monument’s Medicine Lake shield volcano is dormant, this is a region of active volcanic

and seismic activity. Nearby volcanic and/or seismic activity could have a significant impact on cave

geologic features. Cave formations are often broken during earthquakes, and passages and ceilings could

collapse, dramatically changing cave morphology and air currents within the cave. Air currents affect

the deposition of secondary minerals in caves and have a significant effect on ice deposits. New lava

flows or pyroclastic activity could completely change the landscape.

4.2.4 Indicators and Criteria to Evaluate Condition and Trends

Criteria

Some caves have particular features that are more sensitive than others, for example delicate cave coral

walls as opposed to smooth lava walls. Sowers (1992) defined levels of impact for caves in the

monument. A cave that is “highly impacted” would display heavily worn floors, many broken
31

formations, and extensive graffiti. A “moderately impacted” cave would display worn floors, a few

broken formations, and minor graffiti. A cave would be considered “lightly impacted” if the floors are

slightly worn, almost no formations are broken, and there is only very minor graffiti. In a “pristine”

cave, the floor would not be worn, no formations would be broken, and there would be no graffiti. Also, 

a “pristine” cave would contain only in-situ cave sediments in natural depositional environments and

aeolian (wind-blown) sediments. A more quantitative indicator of cave impact is the number of cave 

visitors per year. However, it is a less direct means of representing impacts, and impacts sometimes 

depend more on visitor behavior than total number of visitors.

With regard to trends, “Good” conditions would consist of maintained or improved conditions in nearly 

all the caves, as the conditions are defined above. “Somewhat Concerning” would be adverse changes in 

condition categories (e.g., from “lightly impacted” to “moderately impacted”) in a few caves, and 

“Significant Concern” conditions would be adverse changes in many. 

Condition and Trends

Condition: Somewhat Concerning – Low Certainty. 

Trends: Indeterminate. 

Staff and volunteers have inventoried caves as part of a Cave Research Foundation project, but no

comprehensive dataset or analysis exists. The inventory forms include the criteria described above that 

are relevant for assessing formation breakage and erosion. Sowers (1992) lists examples of caves which

fit each of the criteria, but updates of the descriptions she prepared 20 years ago have not been 

published. As of that time, Catacombs Cave and Skull Cave were highly impacted. Arch, Sentinel, and

Post Office Caves were moderately impacted. Big Painted Cave, Ship Cavern, Heppe Cave, and Cox Ice

Cave were lightly impacted. Copper Rock Cavern and The Bowers Cave are pristine.

Tinsley (1992) studied two impacted caves, Valentine and Skull. Valentine Cave reported a sediment

plume in the entrance room which had a maximum thickness of 200 mm and thinned with distance into

the cave. The sediment plume appeared to be the result of dumped construction debris. The sediment

had been tracked into the cave via transport on visitors’ shoes. This sediment was the result of a onetime action, and transport of sediment out of the cave via visitors’ shoes dampened by moist cave floors

was reported to be occurring at a rate exceeding the rate of input by more than an order of magnitude.

The overall impact of the footgear-based removal process has not been fully determined. In Skull Cave, 

rock surfaces near the entrance of Skull Cave were reported to be coated and discolored with sediment 

transported via visitor foot traffic. Also within Skull Cave, the ice floor was degraded by reddened

particles of rock and soil tracked onto the ice via visitor foot traffic. The reddened sediment originated 

within the cave; however, human traffic moved the sediment onto the ice. 

The chemical composition of ice from 12 caves was determined in summer and fall of 2005 (Currens et 

al. 2006). Baseline measurements included pH, alkalinity, bicarbonate, carbonate, calcium, specific 

conductance, chloride, nitrate, ammonium, sulfate, sodium, potassium, and magnesium. Maximum 

alkalinity was 180 mg/L CaCO3 and 220 mg/L HCO3. Measurements of pH ranged from 5.26 to 9.

Potentially corrosive pollutants have not been reported for any of the caves, either in the air or in runoff

and groundwater that seeps in, but chemical composition of ice from several caves was measured in 

2009-2010 and a report is pending. 
32

Aboveground, levels of atmospheric sulfate deposition in this monument during 2005-2009 were rated 

“Good” based on data interpolated from other parts of the region (NPS-ARD 2011). Risk to the 

monument from acidic deposition is rated low (Sullivan et al. 2011b). The monument is in an area 

designated by Congress as a Class I air quality area, meaning there are increased air quality protections 

in place.

Assessment Confidence and Data Gaps

Low Certainty. Only a small proportion of the monument’s caves have been evaluated in terms of the 

criteria described above, and no database or reports describe those conditions using a standardized 

protocol applied at annual or semi-annual intervals. Photomonitoring is useful in documenting gross

change over time, and a collection of photos of major cave entrances and passages exists. Bill and Perry

Frantz through the Cave Research Foundation have sustained this long term photo-monitoring project,

covering 33 sites within 16 caves, but images are difficult to compare without standard reference points.

The tool will likely be useful for detecting large changes, such as entrance collapse and broken

stalactites, but small changes such as sedimentation, smoothing of surfaces, or breaking of delicate cave

coral are not likely to be captured unless a particular spot was photographed in detail before the damage

occurred. 

Visitor logs and infrared counter data exist for some caves in the highly impacted Cave Loop area and

are being installed in other locations as part of the I&M protocol (Krejca et al. 2010). Each method has

different confidence levels associated with it. Visitor counts are likely to correlate somewhat with

formation breakage and general cave erosion, and these data are collected in various ways. For gated

caves with monument staff required to open the gate, visitation records are very near a perfect reflection

of cave use. Very few of the monument’s caves are gated so other techniques are used. Visitor logs are

not likely to be filled out by every person entering the cave unless there is some type of enforcement

(e.g., a monument staff member requiring it for entry), but they are cost effective and probably sufficient

for remote sites with little visitation. Infrared counter data can be confounded by multiple passes of the

same person into a cave entrance, by large groups entering a cave simultaneously, by vandalism, and by

obstruction from natural features (e.g., windblown vegetation, animals, rockfall). Pressure plate counters

have similar problems. However a combination of all of these methods, varying by site and by level of

use, is useful for obtaining estimates of visitor use and subsequently correlating that with impact to the

cave.

4.3 Changes in Cave-dependent Species

4.3.1 Background

When assessing the condition of cave species, it is helpful to know if its population is part of a larger,

interconnected population (i.e., is a metapopulation) whose members may breed far from the monument,

or if the species is essentially at an evolutionary cul-de-sac and its entire population is genetically

isolated to the monument. It is also helpful to know how dependent a species is on caves. In terms of 

cave dependency, cave organisms are commonly classified as troglobites, troglophiles, or trogloxenes

(Barr 1968). 

Troglobites spend their entire existence underground and cannot survive outside of caves. They typically

are characterized by eyelessness, lack of pigment, adaptation to constant temperatures and saturated

humidity, attenuated appendages, and slow metabolism. Examples in this park include the millipede

Plumatyla humerosa and the dipluran Haplocampa sp.
33

The effective conservation of a troglobite species is aided by an understanding of its evolutionary 

history and, specifically, how recently it evolved separately from its aboveground ancestors. Typically, 

troglobites evolve into separate species as a result of ancient isolating events such as glaciers, lava

flows, or climate changes. In some cases those events may have extirpated their aboveground ancestors 

(Culver et al. 1995). Lava flow caves such as those in this park have many isolated sections, and the 

caves themselves are collectively distant from any other concentration of caves. These factors would 

seem to favor the eventual creation of a rich assemblage of troglobites (Culver and Holsinger 1992).

Troglophiles are obligated to complete some part of their entire life cycle underground, but may forage 

regularly outside. They are more tolerant of climactic shifts and are adapted to more nutrient-rich 

environments. Examples of troglophiles in the monument include most bats, arachnids (such as spiders,

mites, and pseudoscorpions), grylloblattids, myriopods (such as centipedes), and many insects (Taylor

and Krejca 2006).

Trogloxenes use caves, but cannot complete their entire life cycle in the cave. They typically must leave

to forage or mate, and may use caves only sporadically. Nonetheless, caves are important to many of 

these species during critical periods, providing hibernation sites or refuge from the extremes of surface

climate variation. Hibernating animals rely on consistently cold temperatures to trigger and maintain

metabolic functions throughout their dormant period, without which they will expire if forced to ‘awake’

before sufficient food is available on the surface. Examples of trogloxenes in this monument include

some birds (e.g., owls), fox, coyote, and cougar. A few of the troglophiles and trogloxenes may be

modern evolutionary precursors to future troglobites, or they may be species that will never experience

genetic isolation from their surface dwelling relatives. Typically the species with greater physical or 

physiological adaptations to cave life, such as the troglobites, occur deeper inside the caves.

4.3.2 Regional Context 

The bats in this region are insectivores, and they play an important ecological role in controlling insects,

including many agricultural pests. Of the monument’s 14 known bat species, 7 are considered to be of 

greatest conservation priority due to their life history, preferred habitats, or other factors (Table 3). 
34

Table 3. Bat species with special conservation designations documented at Lava Beds National Monument.

Scientific Name Common Name Special Status

Antrozous pallidus Pallid bat CDFW Species of Special Concern

Corynorhinus townsendii Townsend’s big-eared bat CDFW Species of Special Concern

Myotis thysanodes Fringed myotis WBWG = High priority

Myotis volans Long-legged myotis WBWG = High priority

Lasionycteris noctivigans Silver-haired bat WBWG = medium priority

Myotis ciliolabrum Western small-footed myotis WBWG = medium priority

Myotis evotis Long-eared myotis WBWG = medium priority

* CDFW: California Department of Fish and Wildlife

 WBWG: Western Bat Working Group

One lava tube in the monument contains the largest colony in the northern United States of the

migratory Brazilian free-tailed bat (Tadarida brasiliensis). Most of the monument’s cave-dwelling bats 

remain during the winter, using caves as hibernacula sites. Exceptionally large hibernacula of the 

Townsend’s big-eared bat (Corynorhinus townsendii) also occur in the monument. These colonies are

some of the only ones known to be stable or increasing as compared to the remainder of the state which

is experiencing dramatic declines in the numbers of maternity colonies and roosts, and a dramatic 

decline in the total numbers of individuals counted (Pierson and Rainey 1998). The monument’s caves

also support the world’s only known underground nesting sites of purple martin. This bird species is

regionally uncommon. As well, several invertebrate species are known from no other place than from 

the monument’s caves, as documented by Taylor and Krejca (2006) and prior researchers. 

4.3.3 Issue Description

4.3.3.1 Climate and Microclimate Changes

Due to the confined nature of caves, even the simple presence of humans can increase localized 

temperature and humidity, especially in smaller and more confined caves. Normally, cave microclimate 

is influenced by surface temperature, wind, precipitation, ice formation, and cave morphology (see 

section 4.1). Troglobites in particular are sensitive to temperature and humidity. Most are narrowly

adapted to a specific temperature range and quickly expire when exposed to small temperature

variations.

Bats that hibernate locally use certain cold caves for hibernation but use different warmer caves (or 

warmer sections of the same cave) for breeding. In the summer, bats cluster together in domes or

crevices of caves because those trap warm air. The presence of bats’ bodies can increase the temperature 

further and that might support more favorable roosting or breeding conditions. Bats have been known to 

abandon cave roosts after placement of a gate at a cave entrance, and subtle alteration of cave 

microclimate by a gate has been suggested as a possible cause. 
35

4.3.3.2 Effects of Aboveground Plant and Animal Communities

All changes in aboveground vegetation and animals have the potential to affect cave species positively 

or negatively. This includes vegetation and wildlife changes due to fuels management, grazing regime, 

invasive plants, air quality, and water management in surrounding areas, as well as changing climate and 

associated changes in patterns and rates of fire and natural succession. These can affect cave species in 

at least two ways: (1) changing the amount of water that infiltrates into caves and thus the cave 

microclimate, (2) changing the amount of nutrients that are carried into caves. 

With regard to infiltration, some deep rooted plants are capable of penetrating cave ceilings and thus 

facilitating downward infiltration of water into caves, consequently providing habitat for cave 

invertebrates and providing water for ice formation. By shading the aboveground soil surface, other 

plants help maintain cooler summer temperatures at the ground surface. That in turn may help maintain 

belowground temperatures and thus maintain ice formations. Some aboveground shrubs effectively trap 

windblown snow, making more meltwater available for infiltration into caves, but on windy summer 

days other shrubs may transpire such large amounts of soil moisture that significantly less water is 

available for infiltration. Impervious surfaces such as roads and buildings can restrict or redirect 

infiltration that otherwise would influence cave microclimate.

Nutrients from aboveground are essential energy sources for troglobites because little or no sunlight 

reaches cave interiors. Thus, no plant production can occur and food must come in from external sources 

(some production may nonetheless occur among cave microbial communities if they are capable of 

using minerals directly). Potential energy sources for cave organisms are: (a) seeds and nesting material 

carried in by woodrats (packrats), birds, and other animals; (b) plant matter carried into cave entrances 

by windstorms or rare floods; (c) feces (scat, guano) and urine from bats and other wildlife that forage 

outside the cave; (d) plant roots that penetrate the ceilings of shallow caves; and (e) crumbs, hair, dust, 

and threads incidentally attached to clothing of visitors. At low light intensities, fungi grow on the 

decaying organic matter and this in turn feeds many species of invertebrates. Conceivably, an inorganic 

nutrient—atmospheric nitrogen, mainly in the form of ammonium and nitrate—could be deposited in 

wet or dry form on the land surface by precipitation and air currents, and then could infiltrate downward 

into caves. Its potentially stimulative effect on the growth of cave lichens and fungi, at the deposition 

rates known to be present in this park (see section 4.6), has not been studied.

The importance of nutrient inputs is recognized by a recovery plan for federally listed troglobites in 

central Texas (USFWS 2011), which mentions as an objective the maintenance of a natural quantity of

native vertebrate and plant matter input. The recovery plan also mentions the need to maintain a healthy

aboveground native plant and arthropod community and minimize threats from invasive invertebrates. 

As noted before, the type and extent of the nutrient sources for some cave-dependent animals will 

depend on the type of aboveground vegetation, the palatability of that vegetation, and ultimately, on 

aboveground climate, fire, and vegetation management practices. For example, invasive plants that 

outcompete the native food plants of woodrats in aboveground habitats can trigger a decline in woodrats

within caves, which triggers cascading effects on other cave biota due to the consequently reduced 

importation of nutrient-rich organic matter. Air pollution and pesticide application may reduce the food

sources of bats, thereby reducing the energy that comes into the cave in the form of guano.

Both too little and too much nutrient input to a cave can be detrimental to troglobites.
36

Too little incoming nutrient load can reduce numbers of all cave animals, and too much input is

documented to increase the abundance of trogloxenes and troglophiles at the expense of troglobites

(Krejca and Myers 2005). In one study in Texas, the investigators demonstrated an association between 

urbanization, altered isotope ratios (an indicator of the type of nutrient source), and reduced diversity

and abundance of cave invertebrates (Taylor et al. 2007).

4.3.3.3 Contaminants

In addition to affecting cave microclimates and nutrient sources, human visitors potentially introduce

contamination from insect repellent and toxic trash such as batteries. Road runoff contains 

petrochemicals, heavy metals, and herbicides. Pesticides are used widely in the agricultural lands north 

of the monument (Eagles-Smith and Johnson 2012) and can potentially reach the monument, even over 

long distances. Herbicides are used within the monument to control invasive plants. Although herbicides 

are never applied near cave entrances, a potential may exist for some types of herbicides (or their inert 

ingredients or wetting agents) to infiltrate rapidly downward due to the monument’s very porous soils. 

4.3.3.4 Pathogens

In the eastern U.S., several bat species are declining due to infection with a fungus (Geomyces

destructans) that arrived recently from Europe. Named for a distinctive fungal growth around the

muzzles and on the wings of hibernating bats, white-nose syndrome (WNS) has not been confirmed 

among any bat populations west of the Missouri River, but that could change in the future. The mortality

rate of some infected populations has been a staggering 95% in some cases. Symptoms include loss of

body fat, unusual winter behavior (including flying), damage and scarring of the wing membranes, and

death. Infection causes bats to rouse too frequently from torpor (temporary hibernation) and starve to

death through excessive activity. The fungus can grow only in temperatures in the 4 to 15°C range (39–

59°F), a range typical of many caves. It perishes at temperatures above 20°C (68°F). Recent research

suggests that human anti-fungal treatments might help stem the infecting fungus in individual bats, but 

many questions remain. To minimize the threat of WNS reaching the monument’s caves, visitors are 

required to state whether they have recently visited any caves or mines in the areas affected by WNS and 

if so, whether they have decontaminated the boots, equipment, etc. which they are bringing to the 

monument.

4.3.4 Indicators and Criteria to Evaluate Condition and Trends

Recently the Klamath Network of the National Park Service Inventory and Monitoring team worked

closely with monument staff to create a long-term, peer-reviewed monitoring protocol for the region’s 

cave entrance communities and cave environments (Krejca et al. 2010). The team identified and 

prioritized eight general factors that should be the focus of whatever indicators are routinely monitored. 

These factors are based on, among other things, the strength of their connection to the cave ecosystem,

how feasible they are to measure given staff and resources, and the ability to track trends in sample

datasets. The eight include four abiotic parameters (climate, water levels, ice levels, human visitation)

and four biotic parameters (bats, visible scat and organics, entrance vegetation, invertebrates). Two

specific indicators that reflect these broader factors are:

• Condition (presence and persistence) of cave-dependent species

• Condition of cave habitat for cave-dependent species

These are now discussed.
37

4.3.4.1 Condition (Presence and Persistence) of Cave-dependent Species

Criteria

For purposes of this assessment, “Good” conditions would be represented by sustained diversity and

abundance of all cave dwelling species currently inhabiting the monument, or hypothesized to inhabit

the monument prior to human impact. As with any biological system, this would ideally include

sustaining relative proportions of species according to their role in the food web, and sustaining their

genetic diversity in terms of healthy population size and interconnection with other populations. 

“Somewhat Concerning” and “Significant Concern” would represent increasingly greater reductions in

the populations of cave dwelling species.

Condition and Trends

Bats

In general the condition of bat populations in the monument appears to be Good. However, only three of 

the monument’s 14 species have been subject to relatively intensive long-term monitoring efforts. The

remaining 11 species have been monitored opportunistically and thus have insufficient data to 

characterize their population condition or trend.

All or most of the Brazilian free-tailed bats, T. brasiliensis, occur seasonally within the monument in a

single maternity colony in Bat Cave. Bat biologists have described this cave’s habitat in detail, including 

physical and climatic characteristics of the passage (Cross and Ferrell 1984, Fuhrmann 2003). They have 

used photographic techniques to estimate the population size (Cross 1989, Fuhrmann 2003), thermal

videography to estimate the population size (Betke et al. 2008), and dataloggers to track entrance and

exit activity (Shawn Thomas, pers. comm. 2012). Acoustic activity at foraging areas surrounding Bat

Cave was monitored in an effort to determine where T. brasiliensis bats were feeding most often (Cross

and Waldien 1994). Population estimates have ranged between 50,000 and nearly 400,000 individuals

when using photographic methods performed up to three times a year since 1988. But different 

estimation methods give different results. Numbers estimated by thermal imaging, performed only once 

at Bat Cave but on the same night as photographic methods, were many times lower and might be more 

accurate. Fuhrmann (2003) points out multiple problems with the photomonitoring method used since

1988: it is not well suited for making counts in full darkness, it is not perfectly repeatable among

researchers, the historic dataset does not contain a consistent number of pre and post volancy sample

events, and there are microclimate variables not accounted for that may affect flight patterns in any

given night. Recently monument resource staff reviewed the historical datasets and ranked those in order

of confidence so the counts could be used in future analyses. Greater confidence was assigned to

evenings where researchers did not have to switch methods because of light availability.

Another species that has been the focus of some monitoring is Corynorhinus townsendii. A statewide

survey of this species in California indicated a sharp decline, with over half of the historical colonies 

extirpated and with the number of bats in existing colonies in decline, with a notable exception of

several caves in national parks, including Lava Beds (Pierson and Rainey 1998). This is the only bat

species regularly monitored as part of the Klamath Network Inventory and Monitoring protocol.

Monument staff have been tracking colony locations and estimating populations to inform decisions 

about which caves to close to visitors in order to minimize disturbance impacts to the species. The I&M

protocol also calls for monitoring winter hibernacula in the monument (Krejca et al. in prep). 
38

Data exist for summer and winter counts of this species using various protocols, and a report by Ted 

Weller that analyzes trends is in preparation. Figures 12 and 13 show a subset of the entire dataset. 

Based on winter hibernacula point counts performed before protocols were standardized (year?), these

figures suggest stability in numbers at 12 caves which represent the majority of known hibernacula sites

in the monument. Populations may have increased at two of the monument’s maternity roosts in 1961

and 1970, and then again in the late 80s and early 90s (Pierson and Rainey 1998). However, no 

statistical analyses of trends have been published.
39

Figure 12. Winter hibernacula counts of Corynorhinus townsendii at 12 caves (coded to protect roost site

information) from 1998 to 2010. (From Krejca et al. 2010.)

1998 2000 2002 2004 2006 2008 2010 2012

0 100 200 300 400 500 600 700

Year

C. townsendi Hibernacula Count

1

4

12

13

17

25

27

30

31

40

44

56
40

Figure 13. Log transformed winter hibernacula counts of Corynorhinus townsendii at 12 caves (coded to protect 

roost site information) from 1998 to 2010. (From Krejca et al. 2010.)

Pallid bats, Antrozous pallidus, were formerly known from a single colony in the monument, but in 2010

a second colony was discovered and is being loosely monitored (Shawn Thomas, pers. comm. 2012).

Other species of bats are detected sporadically, by using mist nets and harp traps, for example (Tyburec

1999), but condition and population trends are unknown. No condition or trend data are available for

other bat species. 

In many parts of North America, bat populations are threatened by disease epidemics, loss of roosting or

foraging areas due to landscape changes, and impacts from pesticide use (Rodhouse et al. 2012). 

Because many of the monument’s bats forage outside of the monument and migrate to distant regions, it

is possible they suffer from such impacts. 

1998 2000 2002 2004 2006 2008 2010 201

0

2

4

6

Year

C. townsendi Hibernacula LOG(Cou

1

4

12

13

17

25

27

30

31

40

44

56
41

Other Cave-associated Mammals

The condition and population trends of the monument’s cave-associated mammals, such as woodrats 

(Neotoma spp.) and deer mice (Peromyscus spp.), are Unknown. An exception is American pika

(Ochotona princeps), a rabbit-like animal that uses cave entrances and lava flows. Recent studies in the

monument have addressed pika abundance, distribution, habitat associations, management, habitat 

occupancy, and gene flow (Shardlow et al. 2009, Ray and Beever 2007). Those studies indicate that pika 

populations in the monument appear to be occupying most of the habitat considered to be suitable, 

although this has not been quantified. Thus, the condition for pika is rated Good, despite the apparent 

disappearance or decline of the species in many areas of the American West. However, the certainty of 

this estimate is Low, and trend is Indeterminate.

Cave-associated Birds

The condition and population trends of the monument’s cave-associated birds are mostly Unknown. The 

main exception is purple martin, whose numbers (at the caves where they nest just inside the entrances) 

have been monitored irregularly since the 1960s and regularly using a standardized protocol since 2003. 

No long term trend is apparent, but in 2011 the numbers were markedly low (David Larson, pers. comm.

2012). This is not necessarily attributable to conditions in the monument, as they spend much of the 

winter in regions far to the south. Other species that occur to varying degrees just inside the monument’s 

caves include violet-green swallow (nesting), Say’s phoebe, rock wren, canyon wren, common raven, 

barn owl, and great horned owl. None of these is generally a cave dependent species.

Cave-associated Amphibians and Reptiles

Only one species—Pacific treefrog—regularly inhabits the cave entrances and, within the monument, 

may be dependent on this moist environment, although the species is not confined to caves. Rubber boas 

are found regularly in the monument’s caves. Due to lack of standardized inventory data, the condition 

and population trends of these two species are Indeterminate.

Cave Invertebrates

Similarly, the condition and population trends of the monument’s cave-dependent invertebrates are 

Unknown. Three studies to date (Crawford 1990, Ferguson 1992, Taylor and Krejca 2006) have 

determined which species occur in each of the major caves, but provide no context to indicate the

relative condition of the monument’s cave-associated invertebrate fauna. At least a dozen species may

be cave obligate (troglobitic) species. Two of these (an isopod and a pseudoscorpion) may be endemic to 

the monument (Taylor and Krejca 2006). 

Cave-associated Plants and Lichens

Lichens are diverse and abundant in the monument. While no comprehensive database exists, one study

(Vanover et al. 2008) found decreased lichen and moss coverage at caves with greater visitation,

although slope, elevation, and aspect were not controlled for. This suggests that some lichen species

might not tolerate disturbance from human visitation, but specific thresholds and causative factors are 

Unknown. Disjunct populations of several fern species, including western swordfern (Polystichum

munitum), dominate some of the monument’s cave entrances. The condition and trend of these ferns and 

other plants associated with cave entrances has not been quantified, but surveys are ongoing. 

Assessment Confidence and Data Gaps

Low Certainty. With the exception of two of the monument’s 14 bat species, condition and trend data 

collected using standardized protocols is lacking for all of the monument’s cave-associated fauna and 
42

flora. Recent discoveries of many new species of cave-obligate invertebrates at other western 

monuments (Cokendolpher and Krejca, 2010, Disney et al. 2011, Shear et al. 2009, Shear and Krejca 

2007, 2011) indicate that further sampling and taxonomy effort at Lava Beds is likely to reveal more 

cave-obligate invertebrate species, perhaps including some that are endemic to the monument. In 

comparison with efforts to document invertebrates of lava tubes elsewhere in the western US (e.g., 

Northup and Welbourn 1997), the monument has received very little study of its cave invertebrates. 

4.3.4.2 Condition of Cave Habitat

For purposes of this assessment, “Good” conditions would be represented by a pristine cave

environment not showing effects of humans. This includes no changes to microclimate (e.g. changes to

ice levels or presence of structures or alterations of entrances), no measurable effects of human visitation

(e.g. sediment deposition, formation breakage), and no pollution. “Somewhat Concerning” and

“Significant Concern” would represent increasingly signs of damage to the cave environment as a result 

of human actions. Sections 4.2.4.1 and 4.2.4.3 of this report describe in more detail the effects of human

visitation (formation breakage, general cave erosion and sediment deposition). Sections 4.2.4.2 and 

4.1.4.2 cover ice levels. Section 4.1.4.1 covers cave microclimate. Section 4.2.4.4 covers groundwater

pollution.

4.4. Changes in Vegetation

4.4.1 Background

Vegetation is a foundation for terrestrial ecosystem composition, structure, and function. Vegetation

ranked as a key vital sign for monitoring of ecological integrity in the Klamath Network Inventory and

Monitoring Program. Vegetation composition includes an array of ecosystem components such as

species, populations, genetic composition, and special habitats. Vegetation structure refers to the vertical

and horizontal arrangement of components, such as canopy structure and corridors for species

movement. Vegetation function refers to ecosystem processes such as cycling of nutrients, carbon, and

water—which interact with disturbance processes and biological components such as interspecific

competition and demographic and reproductive processes. Vegetation dominates biomass and energy

pathways and defines the habitat for most other forms of life. Indicators for vegetation composition,

structure, and function can therefore define the ecological integrity of terrestrial ecosystems.

Vegetation structure, function, and composition can be altered by many activities (e.g., fire

management) or from extrinsic factors (e.g., off-site pollution, climate change, invasive species) (Figure 

14). These affect the structure of the habitat, particularly the disturbance regimes, as well as the

landscape patterns that create habitat for a wide variety of species.
43

Figure 14. Human influences on the structure, function, and composition of ecosystems.

Elevation-driven changes in moisture and temperature yield marked zonation in vegetation at the 

monument. These factors interact with substrate age (i.e. the age of various historic lava flows) and

topography to help produce the vegetation mosaic (Figure 15). Sagebrush (Artemisia tridentata) 

communities dominate the lower elevation valleys and plateaus. With increasing elevation from north to 

south, sagebrush decreases somewhat in frequency (though it remains abundant) while western juniper

(Juniperus occidentalis), mountain mahogany (Cercocarpus ledifolius var. intermontanus) and 

vegetation height and abundance increase. At higher elevations and more mesic sites (i.e., north facing

slopes), ponderosa pine (Pinus ponderosa) dominates. Ponderosa stands in isolated cinder cones are

mainly undisturbed, but ponderosa forests along the monument’s southern boundary have been

profoundly altered in recent history. Railroad logging, clearing, and a major stand-replacing fire around

1915, before the monument was established, had dramatic effects. Almost all the remaining pines have

regrown since these events, and the ecotone between juniper woodland and ponderosa forest has shifted

south and higher in elevation. Widely scattered large-diameter stumps and snags in the southern third of

the monument, particularly in the Valentine Flow and southeastern areas, now are surrounded by juniper

and mountain mahogany woodlands. 

4.4.1.1 Sagebrush Steppe Zone

Sagebrush steppe dominates the northern two thirds of the monument where elevations range from

1219-1524 m (4000-5000 ft). Sagebrush communities are typically co-dominated by shrubs and grasses. 

Grasses include both native bunchgrasses and introduced cheatgrass (Bromus tectorum). Fires in recent

years killed most shrubs in the northernmost portion of the monument. Consequently, this area is

dominated by grasses, particularly cheatgrass, and another non-native species, herb sophia (Descurainia

Far-field 

Influences

Near-field 

Influences

ECOLOGICAL INTEGRITY OF ECOSYSTEMS

Local Disturbance

Point Source 

Pollution

Visitor Use Function

Disturbance 

Regimes

Water, 

Energy, & 

Nutrient 

Cycling

Biological 

Interactions,

Demography,

Reproduction

Structure

Abiotic

Gradients

Biotic 

Gradients

Spatial

Pattern

Fire Suppression

Global Warming

Invasive Species

Diffuse Pollution

Urban Encroachment

Composition

Focal 

Communities 

Rare & 

Sensitive

Species 

Keystone 

Species

& Ecosystems
44

sophia). This shift to grass domination may persist as Great Basin shrubs are slow to regenerate from

seed and fire may recur before this can happen. Probability of fire recurrence is enhanced by cheatgrass, 

which has positive feedback relationship with fire, both promoting and being promoted by fire

(D’Antonio and Vitousek 1992). Over the last several decades cheatgrass has become the most 

widespread and abundant plant in the monument, based on 169 vegetation mapping plots that span the 

range of variation in vegetation (Odion et al. in prep). Cheatgrass is common in all the main vegetation 

types, but is most common at the north end of the monument. 
45

Figure 15. General vegetation map of Lava Beds National Monument. The map is reproduced from the 2010 

Draft General Management Plan and Assessment (Map 15). 
46

The unburned sagebrush steppe consists of open shrublands of Great Basin sagebrush (Artemisia

tridentata subsp. tridentata), native bunchgrasses and cheatgrass. Common bunchgrasses include

squirreltail grass (Elymus elymoides), Thurber’s needlegrass (Achnatherum thurberianum), bluebunch

wheatgrass (Pseudoroegneria spicata subsp. spicata), Sandberg bluegrass (Poa secunda), and scattered

native herbs (e.g., Agoseris spp., Nothocalais troximoides, and Astragalus spp.). These plant

communities occupy deep well-drained soils. Common woody associates include the deciduous shrubs

gray rabbitbrush (Chrysothamnus nauseosus), and yellow rabbitbrush (Chrysothamnus viscidiflorus). 

They also occasionally include antelope bitterbrush (Purshia tridentata), a nitrogen-fixer and favored 

deer food, and the spineless horsemint (Tetradymia canescens). Gnarled old junipers occasionally occur

in the sagebrush-steppe, most often on rocky outcrops.

A community dominated by desert gooseberry (Ribes velutinum) and basin wildrye (Leymus cinereus), a 

very large bunchgrass, occurs in the northeast corner of the monument at the lowest elevations (Erhard 

1979, Smith 2009). Basin wildrye is an indicator of pluvial lake plains (former lakebeds) (Young et al. 

2007). This seasonally moist community occurs in areas with accumulations of erosionally deposited

volcanic ash (Young et al. 2007). Associated species include the shrubby to small tree willow (Salix

lasiandra subsp. lasiandra), and herbs such as water smartweed (Persicaria amphibium var. emersum),

and a stinging nettle, Urtica dioica var. holosericea. Shrublands dominated by rabbitbrush also occur in

the extreme northern portion of the monument where grazing and the draining of Tule Lake have 

modified natural vegetation. In the northern portion of the monument, on Gillem’s Bluff at sites with

shallow soils, there occurs an association of the aptly named low-sage (Artemisia arbuscula). The tufted

perennial bunch grass, Festuca idahoensis, occurs with the low sage. Also on Gillem’s Bluff, on the

north sides of volcanic outcrops, there are patchy communities of the deciduous subshrub, roundleaf 

snowberry (Symphoricarpos rotundifolius var. rotundifolius), with an understory of Idaho fescue and the

blue-flowered herb, hackelia (Hackelia cusickii). 

4.4.1.2 Juniper and Mountain Mahogany Zone

The juniper and mountain mahogany woodland communities occupy much of the southern third of the

monument, at elevations ranging from 1310-1615 m (4300-5300 ft). The woodlands represent a midelevation ecotone between the warmer drier lower elevation sagebrush steppe vegetation and the cooler

moister higher elevation coniferous forest vegetation. In addition to western juniper and mountain 

mahogany (Cercocarpus ledifolius var. intermontanus), the low-growing and deciduous antelope

bitterbrush and to a lesser extent mountain big sagebrush (Artemisia tridentata subsp. vaseyana) are the 

dominant shrubs (note: the sagebrush at lower elevations is Artemisia tridentata subsp. tridentata). 

Erhard (1979) noted one small community of antelope bitterbrush, and bluebunch wheatgrass on the

southern slope of Hippo Butte. The boundary of this community is undefined and it grades into the

surrounding sagebrush-steppe. Mountain mahogany communities in the monument occur on undulating

basalt with little soil development and little forb cover (Erhard 1979, Smith 2009). Associated species

include the deciduous shrubs, bitter cherry (Prunus emarginata) and currant (Ribes spp.), Sandberg’s 

bluegrass (Poa secunda), cheatgrass, and fragile fern (Cystopteris fragilis). 

The mountain big sage communities in this zone often have antelope bitterbrush as a codominant and

bunchgrasses, bluebunch wheatgrass, Idaho fescue, and junegrass (Koeleria macrantha) as the

understory dominant. These associations are the most mesic of the sagebrush communities (Young et al.

2007). Associated species include showy herbs such as fritillary (Fritillaria atropurpurea), old man’s 

whiskers (Geum triflorum), claytonia (Claytonia rubra subsp. rubra), dwarf flax (Hesperolinon
47

micranthum), skullcap (Scutellaria nana), fleabane (Erigeron spp.), groundsmoke (Gayophytum spp.),

and flax (Linum lewisii var. lewisii).

Although some have voiced concerns about the spread of western juniper within the monument, it is 

rarely the most common species in any of the plant communities. One exception may be the large 

Juniperus occidentalis community on the gently rolling terrain of the Valentine flow, in the southeast 

corner of the monument. Associated species include mountain sagebrush, western needlegrass,

bluebunch wheatgrass and the showy herbs tidy tips (Layia glandulosa), penstemon (Penstemon spp.),

and rock cress (Arabis spp.). Less extensive juniper communities occur on the east, west, or south slopes 

of cinder cones in the monument with mountain mahogany as a codominant at these sites.

4.4.1.3 Pine Forest Zone

Communities dominated by ponderosa pine occur in the southern portion of the monument, extending

down to 1402 m (4600 ft) on the northern aspect of cinder cones, but mostly occurring above 1524 m

(5000 ft). The shade tolerant white fir (Abies concolor) and incense cedar (Calocedrus decurrens) occur

in the understory. With the absence of fire these trees may be increasing in abundance (Erhard 1979, 

Smith 2009). Antelope bitterbrush is a common shrub in ponderosa pine woodlands, along with montane 

chaparral species such as greenleaf manzanita (Arctostaphylos patula) and tobacco brush (Ceanothus

velutinus), which have fire-stimulated seed germination. These shrubs occur in relatively pure stands 

where, historically, stand-replacing fires allowed them to establish and/or maintain their populations. 

Less common are two species of currant (Ribes roezlii var. roezlii and Ribes cereum), and other shrubs

like chokecherry (Prunus virginiana var. demissa) and goldenbush (Haplopappus bloomeri). The

dominant grasses include bunchgrasses from the sagebrush steppe, such as bluebunch wheatgrass and

Idaho fescue.

4.4.1.4 Lava Flows, Caves, and Cinder Cones

Because the southern slopes of cinder cones are dry, harsh environments, they support assemblages of

locally rare species that are specialized for those conditions. These assemblages include widely-spaced

shrubs and subshrubs such as slender buckwheat (Eriogonum microthecum), desert purple sage (Salvia

dorrii var. incana), and coyote mint (Monardella odoratissima), along with the distinctive Sacramento 

waxy dogbane (Cycladenia humilis). Associated species include the herbs, dwarf purple monkeyflower 

(Mimulus nanus), ballhead ipomopsis (Ipomopsis congesta), and the diminutive and state-listed rare

plant, doublet (Dimeresia howellii).

The relatively recent andesite flows in the monument are sparsely vegetated. The bare, rough, and dark 

volcanic rock provides junipers refuge from fires, to which they are sensitive, and many grow to be 

fairly large. Lava flows also feature purple sage and desert sweet (Chamaebatiaria millefolium).

Additional shrubs in this harsh habitat are large and ancient looking mountain mahogany as well as wax 

currant (Ribes cereum), and small leaf mountain creambush (Holodiscus microphyllus var. glabrescens). 

The most common forbs are hot rock penstemon (Penstemon deustus), lanceleaf figwort (Scrophularia

lanceolata), and small-leaved giant hyssop (Agastache parviflora).

Cave entrances within the monument support assemblages of many of these same species, especially

desert sweet. Locally rare or disjunct species may be found right next to cool cave mouths, especially

ferns, such as sword fern (Polystichum munitum) and a variety of lichens and mosses (Steven Jessup,

Southern Oregon University, pers. com). The occurrence of sword fern is unusual because it is more

common near the coast, with the nearest known other occurrence being about 120 km (75 miles) west of 
48

the monument. Wood fern (Dryopteris expansa) has a similar disjunct distribution. Ferns in the cave 

entrances are described in Smith et al. (1993).

4.4.2 Regional Context

Lava Beds National Monument encompasses unusual geology (young basaltic pahoehoe lava flows) and

occurs in a transition zone between the Great Basin, characterized by extensive Artemisia sage-steppe

vegetation, and the Cascades, characterized by conifer forests. As a result, the monument’s vegetation 

blends elements of both regions: elements associated with very young geologic substrata, where primary 

succession is occurring, with elements associated with older geologic substrata, where regional 

vegetation has developed. The monument’s most common shrubs — Great Basin sagebrush, antelope 

bitterbrush, rabbitbrush, and mountain mahogany — are Great Basin species. However, species that are 

not characteristic of the Great Basin are also common at the monument. For example serviceberry 

(Amelanchier alnifolia var. semiintegrifolia) is more commonly found along the Pacific coast to the high

Sierra Nevada, and from the northern Rocky Mountains to Alaska. Two species common in the

Cascades and Sierra Nevada, bitter cherry (Prunus emarginata) and bush chinquapin (Castanopsis

sempervirens), occur sparsely at the monument and elsewhere on the western edge of the Great Basin

(Mozingo 1987). Sierra gooseberry (Ribes roezlii var. roezlii), which normally is found in the Sierra 

Nevada mountains, occurs on cinder cones in the southern portion of the monument. The intermixing of 

sage-steppe and montane conifer communities is uncommon in the Great Basin (Young et al. 2007). 

Moreover, recent geologic phenomena, such as cinder cones, lava flows, and associated lava tubes,

create unusual and diverse topography, varied soil conditions, and unusual microclimates. These 

facilitate species occurrences outside their normal ranges. Thus, the monument contains a wealth of

botanical resources and anomalies within a relatively small area. These resources have been described in 

master’s theses (Erhard 1979, Smith 2009), and a flora (Smith 2009). We use these sources in our 

descriptions herein.

The monument contains some of the best examples in the western Great Basin of sagebrush steppe with 

an abundant bunchgrass component and limited cheatgrass component (as discussed below, there are 

also areas, particularly at the north end of the monument, that are heavily infested with cheatgrass).

Areas with relatively little cheatgrass are unusual in the Great Basin because early settlers burned and 

seeded much of the sagebrush-steppe to improve forage for cattle and sheep, which do not eat sagebrush 

and juniper. But, the rocky Lava Beds landscape appears to have provided some refugia where grazing 

impacts, as well as the occurrence of fire, were lower. 

4.4.3 Issues Description

Non-native, invasive species are a significant threat to native plant communities in virtually all natural

areas and threaten the core goals of the National Park Service. Not surprisingly, invasive plants ranked

as the top vital sign for monitoring within the Klamath Network Inventory and Monitoring Program of

the Park Service. In many regions, invasive species are second only to habitat loss as a threat to native

biodiversity (Wilcove et al. 1998). While many invasive species are relatively benign, impacts from

certain invasive species may include the replacement of native vegetation (Tilman 1999), the loss of rare

species (King 1985), changes in ecosystem structure (Mack and D’Antonio 1998), alteration of nutrient

cycles and soil chemistry (Ehrenfeld 2003), shifts in community productivity (Vitousek 1990), changes

in water availability (D’Antonio and Mahall 1991), and, most relevant to Lava Beds, alteration of

disturbance regimes and attendant consequences (Mack and D’Antonio 1998).
49

Across the Klamath network, the number of non-native species decline sharply from low elevations of

Whiskeytown to the higher elevations at Lassen. This pattern has been well-established in the western

U.S. (Mooney et al. 1986, Rejmanek and Randall 1994, Schwartz et al. 1996, Keeley et al. 2011). The 

monument appears to be much more threatened to be significantly degraded by invasive species than 

any other park in the Network because of its relatively low elevation and the presence of one 

exceptionally invasive, ecosystem transforming plant: cheatgrass. Although it must be noted again that 

Lava Beds has some of the least-cheatgrass-invaded sage-steppe anywhere. This increases the regional 

significance of Lava Beds and is a feature of the monument that would be valuable to preserve. 

4.4.3.1 Cheatgrass

Cheatgrass (Bromus tectorum) is a widespread invasive from Eurasia, occurring throughout the 

monument and Great Basin. It is one of the world’s most significant invasive species problems 

(Daubenmire 1940, 1968, Mack 1981). Cheatgrass invasion in the Great Basin has been described by

Aldo Leopold in A Sand County Almanac (1949) as a particularly significant environmental disaster that 

has come to be remarkably well-accepted. Thus, there can be very different levels of concern associated 

with cheatgrass invasion. Herein, we consider cheatgrass invasion to be a serious form of degradation 

because it substantially alters natural conditions and perhaps functions in the monument. This is also 

consistent with NPS policies and with the Klamath Inventory and Monitoring Network, which 

considered invasive species to be one of its top vital signs of ecological integrity. 

Cheatgrass and other invasive species have been monitored in 138 fire monitoring plots in the 

monument under the NPS fire management program. Half of the plots have been within burns and half 

not. These data appear to be suited to a before-after control impact assessment design (BACI: StewartOaten and Bence 2001) to determine the specific effects of fire on cheatgrass, with elevation and other 

factors as covariates. The approach would involve analyzing changes in cheatgrass before and after fire, 

and comparing the difference with changes in unburned plots over the same time period to account for 

changes caused by variation in rainfall and other factors other than fire. The analysis would need to 

consider a time period of several years after fire because the first year response may be unrepresentative 

of longer-term levels. This type of analysis would require use of all the monitoring data and addressing a 

variety of complications, and was therefore considered beyond the scope of this condition assessment. 

Ideally a BACI assessment would be completed with fire monitoring funding. Comparisons of burned 

vs. unburned plots without a before-after assessment assumes that differences with unburned plots are 

all caused by fire and does not account for other differences that could affect cheatgrass invasion in a 

plot. Therefore, we did not want to rely on these kinds of assessments. In the absence of a statisticallyrigorous assessment of the fire monitoring data, we rely on findings from a large literature on the general 

relationship between cheatgrass invasion and fire, focusing on longer-term observations in the western 

Great Basin by eminent ecologist W.D. Billings. 

Cheatgrass can, via its flammable nature, cause conversion to grasslands from shrublands and 

woodlands that are not fire-adapted and which naturally burn infrequently. Cheatgrass can also dominate 

in ponderosa pine forests after wildfires or prescribed fires (Kerns et al. 2006). It is favored by fire 

(D’Antonio and Vitousek 1992) and the scale of the fires which accompanied its spread in the early 

1900s in the western Great Basin has been described as unprecedented (Billings 1990, 1994). In 

contrast, when the herbaceous vegetation in the sagebrush-steppe was occupied mainly by bunchgrasses, 

there was much less fine fuel to carry fire. Early surveys in the western Great Basin mentioned no fire 

scars on the landscape, nor did they mention cheatgrass (Billings 1990, 1994). Cheatgrass invaded 
50

overgrazed systems and once present, it occupied much of the open space between shrubs, greatly 

increasing the capacity for spreading fire. 

Cheatgrass is especially prevalent after fire because fires often kill the woody vegetation and release a

pulse of nutrients that increase cheatgrass growth (Billings 1990, 1994, Chambers et al. 2007). In 

contrast, woody vegetation in Great Basin plant communities is very slow to redevelop after fire, and 

may be slower when competing with cheatgrass (Billings 1990, 1994). In addition, sagebrush is an 

obligate seeder; it does not sprout and relies on seedling regeneration (Young et al. 2007). Sagebrush 

accumulates no seedbank from which to germinate and grow following fire. However, following fire, at 

higher elevations and more mesic sites in the sagebrush-steppe, bunchgrasses (which are also fireassociated, Wright 1985, Ellsworth and Kauffman 2010) may compete better with cheatgrass and 

bunchgrass abundance confers some resistance to cheatgrass invasion (Chambers et al. 2007, Davies et 

al. 2011, Condon et al. 2011). 

J. Chambers and her colleagues (e.g., Chambers et al. 2007, Mazzola et al. 2010, Condon et al. 2011) 

have found that susceptibility to invasion by cheatgrass varies in different environments within the 

sagebrush-steppe and juniper woodland environments. The susceptibility pattern mirrors the pattern of 

invasion at Lava Beds: that is, invasibility varies across elevation gradients. It appears that this is closely 

related to temperature at higher elevations and soil water availability at lower elevations (Chambers et 

al. 2007). At lower elevations high variability in soil water and lower average perennial herbaceous 

cover may increase invasion potential.

Over time, cheatgrass may give way to a variety of other noxious weeds, such as yellow starthistle 

(Centaurea solstitialis) and medusahead (Taeniatherum caput-medusae) (Young et al. 2007). There do 

not appear to be any observations of this shift occurring at the monument, although yellow starthistle is 

present. The non-native that is most common with cheatgrass is sophia or flix weed (Descurainia

sophia). Its growth is luxuriant after fire when nutrients are abundant, although it may not be as 

persistent as cheatgrass.

Invasive species control efforts do not target cheatgrass at Lava Beds because control of this species is 

considered futile. However, by protecting Great Basin ecosystems from livestock grazing, which 

decreases bunchgrasses that help inhibit cheatgrass, at least modestly, the monument is indirectly 

helping control cheatgrass. In addition, efforts to suppress fire may be considered indirect cheatgrass 

control, whether or not that is a stated goal of fire suppression efforts. An herbicide (imazapic) with the 

trade name “Plateau,” which interferes with the germination process in annual grasses, is available to 

help control grasses like cheatgrass (Garmoe 2010). It remains uncertain whether Plateau has any longterm benefits in controlling cheatgrass, and it may harm some native grasses (Baker et al. 2009). 

Research to date suggests that is it likely to be ineffective in controlling cheatgrass in the long-run 

(Baker et al. 2009, Owen et al. 2011).

With no direct means of controlling cheatgrass, the concern is that fire will cause the monument’s 

sagebrush-steppe and woodlands to be displaced by cheatgrass, and the native vegetation won’t return to 

its former state because a new state—cheatgrass dominated grassland—will be maintained by fire. 

Because the shrubs regrow so slowly, even fires as infrequent as 30 to 50 years could maintain 

vegetation dominated by cheatgrass at the monument, in place of native shrubs. The presence of 

cheatgrass could also slow the regeneration of pines following fires that occur in forests. But it is more 
51

possible at Lava Beds to control fire than compared to other lands, although fires can burn into Lava 

Beds from adjacent lands.

4.4.3.2 Other Invasive Plants

Until 1974, much of the monument was heavily grazed, significantly impacting the native vegetation

and fragile soils, and thus likely increasing the spread of invasive plants. Currently, the monument’s 

proximity to lands disturbed by agriculture makes its flora particularly vulnerable to invasive plants.

Coordination of weed control efforts with the adjoining Tule Lake National Wildlife Refuge may slow

future invasions from refuge lands where those are more weed-infested.

Out of the total of 63 nonnative plant species within the monument, 23 are considered invasive. This 

includes cheatgrass, which has already been discussed above. Invasive plants that have been subject to 

control efforts at the monument include common mullein (Verbascum thapsus)—the efficacy of which 

was studied by Rickleff (2006)—as well as horehound mint (Marrubium vulgare), stinging nettle

(Urtica gracilis), bull thistle (Cirsium vulgare), yellow sweetclover (Melilotus officinalis) and Canada

thistle (Cirsium canadensis). Perennial pepperweed (Lepidium latifolium) has not been targeted. 

In 2007, the Klamath Network prioritized the monument’s invasive species based on a combination of

plot sampling data and the expert opinion of Dave Hays (former Lava Beds GIS specialist), who had 

previously conducted invasive species monitoring through several summers in the monument. A total of

44 non-native plant species were considered for ranking. Of these, three were classified as being in the 

colonization phase, eight in the establishment phase, and 15 species classified as being in the spread or 

equilibrium phases. With relatively few colonization and establishment species, all of them were 

included in monument-wide monitoring for early detection (Table 4). Spread/equilibrium species are 

shown in Table 5.
52

Table 4. Prioritized invasive species list for monument-wide monitoring at Lava Beds National Monument.

Scientific Name Common Name Invasion Phase

Ranking 

Score

Lepidium latifolium Broad-leaved pepperweed Colonization 0.917

Centaurea solstitialis Yellow Starthistle Establishment 0.776

Linaria genistifolia ssp. dalmatica Dalmatian Toadflax Establishment 0.712

Taeniatherum caput-medusae Medusahead Establishment 0.696

Thlaspi arvense Penny-Cress Colonization 0.622

Cirsium arvense Canada Thistle Establishment 0.612

Melilotus officinalis (and albus) Yellow Sweetclover Colonization 0.591

Isatis tinctoria Dyer’s Woad Establishment 0.532

Torilis arvensis Hedge Parsley Establishment 0.530

Salsola tragus Russian Thistle Establishment 0.527

Kochia scoparia Kochia Establishment 0.461
53

Table 5. Equilibrium species in Lava Beds National Monument and status of which species will be monitored in

the backcountry, and which will not be, for the reason given. 

Scientific Name Common Name Ranking Score Monitor in Backcountry?

Bromus tectorum Cheatgrass 0.618 N (ubiquitous)

Descurainia sophia Pinnate Tansymustard 0.611 Y

Cirsium vulgare Bull Thistle 0.609 Y

Verbascum thapsus Common Mullein 0.584 Y

Tragopogon dubius Goat’s Beard 0.582 Y

Marrubium vulgare Horehound 0.508 Y

Poa bulbosa Bulbous Bluegrass 0.495 N (control infeasible)

Lepidium perfoliatum Clasping Pepperweed 0.491 Y

Lactuca serriola Wild Lettuce 0.479 N (control infeasible)

Urtica diocia Nettle 0.418 N (potentially native)

Vulpia bromoides Vulpia 0.404 N (ubiquitous)

Erodium cicutarium Filaree 0.388 N (control infeasible)

Holosteum umbellatum Jagged Chickweed 0.341 N (control infeasible)

Sisymbrium altissimum Tumble Mustard 0.306 N (control infeasible)

Galium aparine Bedstraw 0.259 N (possibly native)

Ideally a Before-After-Controlled-Impact (BACI) assessment (Stewart-Oaten and Bence 2001), as 

described above for cheatgrass, would be completed with fire monitoring funding to assess impacts of 

wildfires and prescribed fires on invasives. 

4.4.3.2 Juniper

Juniper is a native tree that conflicts with some management goals if it expands into grasslands and 

shrub steppe. There, it can block vistas and reduce the cover of native grasses and shrubs (especially 

those important to greater sage-grouse, see section 4.5) via shading and competition for moisture. At the 

same time, juniper improves habitat suitability for some wildlife species and may support a diverse array 

of epiphytic lichens and bryophytes. The dynamics and determinants of juniper cover expansion or 

contraction are complex, as addressed in a recent review (Romme et al. 2009). The following 

conclusions from that review are relevant to the situation at Lava Beds:

1. Historically, surface fires that were of low intensity had a limited role in juniper/piñon woodlands of 

the Great Basin. When they did occur, they were likely patchy and small in extent (Baker and 

Shinneman 2004). At Lava Beds, Miller and Heyerdahl (2008) found evidence for far more frequent 

fires in forests adjacent to juniper woodlands than evidence for fire in the woodlands themselves. Other 

researchers have recognized that findings of frequent fire in Great Basin forests cannot be extrapolated 
54

to the shrublands and woodlands that adjoin them, at least not in their pre-cheatgrass state (Baker and 

Shinneman 2004, Baker 2006, 2012). Juniper woodlands generally lack the fine fuels necessary to 

spread surface fires and therefore may burn extensively only during the most intense fires. These would 

be fires that occur during high winds, particularly during droughts that reduce fuel moisture to 

particularly low levels.

2. Stand dynamics are often driven by factors other than fire, in particular, climatic fluctuations.

3. Historical fire rotations varied from location to location but were generally very long (measured in 

centuries). Most woodlands exhibit little or no evidence that they sustained widespread fires during the 

lifespan of the stand. 

4. Recent large, stand-replacing fires in juniper and piñon woodlands are, for the most part, similar [in 

behavior] to fires that occurred historically. Cheatgrass invasion may increase fire frequency in 

woodlands and lead to loss of woodlands, but fire behavior in existing woodlands has likely not 

changed.

5. Tree density and canopy have increased substantially during the past 150 years in many juniper and 

piñon woodlands, but have not changed or have declined in others. This may occur due to more fire, as 

facilitated by cheatgrass invasion or climate change. This is important because juniper growth may be 

lessened or reversed even without juniper control efforts. 

6. Mechanisms for the increasing density of juniper are not well understood in most situations and may 

include recovery from past disturbances, natural ongoing expansion, livestock grazing, fire exclusion, 

and effects of climatic variability and rising carbon dioxide (CO2). Livestock grazing increases juniper 

because juniper are unpalatable to livestock, so juniper is not consumed, while competing vegetation is. 

Fire exclusion cannot be the principal explanation for increasing density of junipers because fires were 

never frequent in woodlands. And in shrublands, fire was likely as infrequent as in woodlands, although 

evidence is weaker. 

4.4.3.3 Historical Fire and Human Influences

Fire has opposing effects on cheatgrass invasion and growth of juniper. For some management goals, 

this presents a conundrum: Which should take precedence—minimizing invasion of an ecosystem 

transforming species (cheatgrass) by limiting fire, or allow fire because it is a natural disturbance and it 

might sometimes limit juniper expansion? This is complicated by the fact that it usually is not possible 

to return Great Basin systems to their historical condition, due partly to changed climatic conditions and 

constraints on burning (Young et al. 2007). 

It nonetheless is helpful to consider the past fire regime and the reasons why we cannot return to it. 

However, reconstruction of intervals of past fires at a specific site is difficult or impossible, and the pre 

Euroamerican settlement fire frequency specifically in the sagebrush steppe of northeast California is 

unknown (Young et al. 2007). At a coarse landscape scale, ecologists have recognized that some standreplacing fires have been a normal occurrence in sagebrush dominated communities, pre-dating 

Euroamerican settlement. It also is apparent that many shrubland areas of the Great Basin lack of fire 

evidence and/or adaptation to rapid post-fire regeneration (Billings 1994). For sagebrush-steppe in 

general, estimates of fire frequency range from 50-240 years (Baker 2006, Mensing et al. 2006). 
55

At the monument, historical fire occurrence in woodlands and shrublands was inferred by Miller and 

Heyerdahl (2008) using a succession model as well as from sampling an inferred chronosequence, and 

consideration of the presence of old (>140 years old) junipers. Older plots were determined in part by 

conditions believed to represent old plots, which were then used to define old plots (many plots could 

not be aged). In addition the areas sampled for each vegetation type were limited to a relatively small 

area of the monument. The sagebrush-steppe sampled lacked old junipers, and it was therefore inferred 

that the presence of younger junipers currently means that fire was frequent in the past and kept out 

juniper. However, this does not consider the possibility that grazing, climate, and/or C02 may have 

facilitated the current juniper growth in areas where it did not previously occur. The onset of juniper 

increases in sagebrush-steppe at the monument coincides with both grazing and the end of the Little Ice 

Age. This ushered a general warming trend with periods of increased precipitation. Extensive 

recruitment of western juniper in Oregon in the 1800s and 1900s coincided with a climatically favorable 

period of high winter precipitation, and this occurred on both grazed and ungrazed sites. In addition, 

predictions of ring growth during the past 100 years were improved in regression models that included 

atmospheric CO2 concentration along with precipitation (Knapp and Soulé 2008). Elevated CO2

decreases transpirational water loss, increasing plant water use efficiency. It may also stimulate fine root 

production. Thus, an absence of old junipers does not necessarily indicate that frequent fire was the 

cause. In addition, fires during the 1800s could have been set to increase livestock forage (i.e. 

bunchgrasses). There was a spike in post-settlement fire in many areas of northeastern California 

(Young et al. 2007).

Settlement burning, in many areas, caused a conversion of sagebrush steppe to more grass-dominated 

vegetation, due to the fire sensitive nature of Artemisia. Once this conversion occurred, overgrazing 

eliminated the bunchgrasses in many areas. Since the early 1900s, intentional fires have been greatly 

reduced and current conditions reflect successional processes from an altered system. In the mid 20th

Century, overgrazing left large areas of the sagebrush steppe where shrubs were not decimated by range 

burning, with little plant growth other than sagebrush (Young et al. 2007). The increase in shrubs may 

be a response to cessation of fire, but these fires were, at least in part, intentionally set by settlers to 

eliminate shrubs and promote herbaceous vegetation for livestock (Young et al. 2007). With fires fueled 

by cheatgrass in recent decades, shrubs have again decreased dramatically. 

This context of human influences helps explain why there is uncertainty about the natural state of 

sagebrush steppe and woodlands. Shrub growth and interrelated overgrazing may both be viewed as 

causes of bunchgrass decline. This is complicated by suppression of fires that favor bunchgrasses, but 

may have been largely anthropogenic. The relative importance of each factor and level of 

appropriateness in the context of NPS goals is difficult to determine. Similarly, vegetation dominated by 

bunchgrass may seem natural because, prior to cheatgrass invasion, fires caused conversion to 

bunchgrass. However, these were sometimes deliberate burns to type-convert the shrublands to 

grasslands for grazing. Without these burns, there would have been more time for sagebrush-steppe 

vegetation to redevelop and occupy more of the landscape. An additional difficulty in assessing natural 

conditions for fire is that the flammability and spread of fire in the sagebrush steppe is now 

unconstrained because there are no areas lacking cheatgrass. There are no examples of how the 

vegetation burned when there was less herbaceous vegetation between the shrubs (bunchgrasses are 

often clumped with the shrubs). 

The historic fire frequencies described by Miller and Heyerdahl (2008), which may be rough estimates 

due to the concerns mentioned above and because only a shot-time scale was investigated, varied from a 
56

composite fire scar frequency of 8-9 years in forests10 from 1750-1904, to 150 or more years in 

sagebrush steppe. These estimates illustrate the wide range of natural variability that likely occurred at 

the monument, and how variation in fire may have occurred at relatively fine spatial scales. 

In sum, there are a multitude of factors that make the definition of a reference condition for fire 

extremely difficult at the monument, and restoring former conditions is not a realistic goal. This in turn 

makes it difficult to assess current conditions with respect to fire. Because current fires have different 

ecological effects than historic fires, due to the proliferation of cheatgrass, it is inappropriate to compare 

the influences of present and past fire. We can interpret the effects of two possibilities only: the effects 

of modern fires, and the effects of no fire.

4.4.3.4 Current Fire

The current fire regime at the monument is driven mainly by human ignitions. Overall, out of a total of 

36,514 ha burned since 1910, 14,158 ha burned in lightning caused fires, 21,039 burned from human 

ignited fire, and 1,316 ha burned from unknown causes of ignition. All of the vegetation types at the 

monument experienced only wildfires prior to 1973 (Figures 16 a-d). There was a large amount of 

wildfire (almost 20,000 ha) in the 1940s, and relatively little any other time prior to the 1970s. About 

one-third of this wildfire resulted from human ignitions. Since 1973, most fire has been from human 

ignitions and deliberate burning, although wildfire in 2008, the lightning-ignited Jack fire, did burn 

about 2,000 ha of sagebrush steppe. 

In Figures 16 a-d, recent fire at the monument is summarized for each broad vegetation type as of 1979, 

when the most detailed vegetation map was prepared by Erhard (1979)11. The distribution of some of the 

mapped vegetation has changed since then as a result of fires. Some areas mapped as grassland in the 

1970s that burned prior to that may have been sagebrush-steppe at the time of fire, and were converted 

to grasslands by fire. Thus, the area of grassland that burned is likely to be considerably exaggerated and 

may have been mostly sagebrush-steppe. A vegetation map from the time each major fire occurred 

would be needed to provide an estimate of the cumulative burned acreage of each vegetation type. This 

is not possible.

Even with such maps, there would be inaccuracy because considerable area within the perimeter of 

burns, called residuals, may not burn (Gutsell and Johnson 2007). Residuals occur in most fires and may 

be important for wildlife and as postfire colonization sources. Residuals are especially likely in 

vegetation like sagebrush-steppe and woodlands, particularly in landscapes like at Lava Beds, where 

there are rocky areas with insufficient fuel to carry fire. Because of this, it is likely that mapped burned 

area may be overestimated by a considerable amount, perhaps 10-20 percent, at least in the case of 

wildfires. In prescribed fires, residuals may get burned with the assistance of fuel from drip torches. 

However, because prescribed burns may often occur in conditions less favorable to fire than wildfires, 

 

10 The composite fire interval is a different metric than the average fire interval. It can be influenced strongly by the 

sampling intensity and scale. The average fire interval is captured by the fire rotation.

11 Vegetation communities mapped were combined into the broad categories using the following criteria: Forests 

included all communities with ponderosa pine, the only tall conifer listed as a dominant; grasslands included all 

communities with no woody species listed as dominants; sagebrush-steppe included all communities having one 

or more shrubs listed as dominants and no juniper or mountain mahogany; woodlands included all communities in 

which juniper and/or mountain mahogany were dominants and ponderosa pine was not dominant.
57

there may also be more unburned area. It is not uncommon to have areas with individual shrubs burned 

or partly burned with the help of drip torch fuel, and inter-shrub areas unburned.

Rotations of fire from the time period 1910-1973, in which no prescribed fires occurred, were very long 

for the ponderosa pine forests because these forests experienced almost no fire (Table 6). With the 

introduction of prescription burning in 1973, the amount of fire in these forests has increased 

considerably. The 63 year fire rotation since 1990 is still longer than the fire frequency (3-37 years from 

1750-1904) recorded on ponderosa pines on three buttes by Miller and Heyerdahl (2008). It is not clear 

if areas off the buttes would have burned with the same frequency as areas on the buttes and whether 

some historic fires were the result of settlers. 

In contrast, rotations for sagebrush-steppe over the 1910-2010 time period, and for woodlands since 

prescription burning began in the 1970s (Table 6), were an order of magnitude shorter (i.e., more fire) 

than those estimated for sagebrush-steppe or woodlands in the Great Basin prior to fire suppression 

(Romme et al. 2009, Baker 2006). However, for Lava Beds, Miller and Heyerdahl (2008) note that 

absence of large live or dead junipers is an indication of sagebrush vegetation burned frequently enough, 

possibly <25 years, to have precluded juniper growth (Miller and Heyerdahl 2008). Alternatively, it 

could also be that absence of old-growth junipers in sagebrush may be due to climate that was not 

suitable over a long-enough time span to allow for development of such junipers in the sagebrush areas 

where juniper is currently encroaching (Romme et al. 2009). In the sagebrush where live or dead oldgrowth junipers do occur, Miller and Heyerdahl (2008) estimate that fire intervals were much longer, 

with >80 year fire-free periods. These periods are substantially longer than those that currently occur 

under the prescribed fire regime (Table 6). In woodlands, fire rotations have decreased dramatically (i.e.,

more fire) from 161 years during the wildfire era to only 29 years in the prescribed burning era. In the 

juniper woodland vegetation sampled by Miller and Heyerdahl (2008), live junipers over 250 years old 

may indicate that fire rotations were very long, perhaps centuries long. So, a substantial increase in fire 

during the prescribed burning era over historical levels appears to be occurring in most sagebrush areas 

and woodlands at the monument. 
58

0

50

100

150

200

250

300

350

400

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Hectares burned

Decade ending (year)

A. Forest 

Wildfire Prescribed fire

0

100

200

300

400

500

600

700

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Hectares burned

Decade ending (year)

B. Grasslands

Wildfire Prescribed fire
59

Figure 16 a-d. Fire occurrence by decade in major vegetation types at Lava Beds. Vegetation is from 1970s 

mapping by Erhard (1979). Some vegetation would have differed at the time fire occurred than when the 

vegetation was mapped.

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Hectares burned

Decade ending (year)

C. Sagebrush-steppe Wildfire Prescribed fire

0

500

1000

1500

2000

2500

3000

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Hectares burned

Decade ending (year)

D. Woodlands

Prescribed fire Wildfire
60

Table 6. Fire rotations in major vegetation types at Lava Beds for different time periods since 1910.

Vegetation

Fire rotation (years)

1910-1970 1971-2010 1990-2010

Forest 1772 101 63

Grassland 119 79 67

Sagebrush-steppe 33 35 29

Woodlands 161 52 28.6

All 53.1 44 32

4.4.3.5 Climate Change and Future Fire

Fire regimes will change in the future, but exactly how is difficult to predict due to climate variations

and potential modifications in fire suppression approaches. In terms of climate, fire frequency in the

Pacific Northwest has been found to be correlated with the warm phase of Pacific Decadal Oscillation

(PDO) (Beaty and Taylor 2008, Miller et al. 2009), which oscillates on a frequency of about 25 years (a 

complete cycle is about 50 years). This relationship may be enhanced by fire suppression, or 

alternatively, the relationship may have been weak prior to fire suppression (Morgan et al. 2008, 

Heyerdahl et al. 2008). From the 1970s until recently, PDO has been in the warm phase, but has recently

shifted to a cool phase (Mantua 2000) particularly in the last 4-5 years. Thus, in the absence of other

climate factors, fire in the Pacific Northwest should occur at lower amounts than the last 25 years. 

However, this does not consider the effects of climate change. A recent analysis predicts a near doubling

by the 2080s of the mean area burned between 1980 and 2006 in Washington (Littell et al. 2010). This

prediction assumes decreased summer precipitation as a main driver of more fire, but data indicate a

pattern of increasing, not decreasing, summer precipitation in the Pacific Northwest (Mote 2003, Hamlet

et al. 2007). In terms of actual patterns in fire occurrence under changing climate, there is no ongoing

trend in the proportion or amount of fire that is high in severity in the drier portions of the Cascades

(Hanson et al. 2009) or Pacific Northwest. Thus, there may be factors that are mitigating the effects of

warmer temperatures on fire behavior. In dry fuels, wind speed is the most important factor in

determining fire behavior (Cruz et al. 2004, Cruz and Alexander 2010). Recent research indicates that

with climate change, the wind speed probability distribution may be shifting towards slower winds,

particularly in mid-latitudes (Pryor and Barthelmie 2010, Pryor and Ledolter 2010). Pryor and her

colleagues found that wind speeds appear to be waning in most of the USA, in many locations by more

than 1 percent per year. Slower winds may be disproportionately important because of the exponential

relationship between wind speed and fire intensity (Byram 1959, Albini and Baughman 1979).

There also is a trend of increased summer precipitation in the Pacific Northwest (Mote 2003, Hamlet et

al. 2007). In forests, this could mitigate the effects of warming temperatures on fuel moisture, a second

key determinant of fire behavior. However, in shrublands and woodlands, increased precipitation may 

increase fire risk due to its effects in promoting more cheatgrass. Recall that Billings (1994) found a 

strong relationship between precipitation and fire in his study area in the western Great Basin. Another 

factor that will affect future fire is ignitions by humans. Human ignitions are rising in many areas due to 

human population growth, more roads, etc. (Syphard et al. 2009). However, these factors should have 
61

less effect at the monument, where there may be greater potential to manage human ignitions than there 

is on other lands in the Great Basin. 

In sum, it is very difficult to predict future fire amounts, but they are most likely to increase, perhaps 

only slightly, unless climate change causes a reduction in cheatgrass. In that case, fire would likely 

decrease.

4.4.4 Indicators and Criteria to Evaluate Condition and Trends

The indicators of vegetation structure, function, and composition in Table 7 were chosen for use in this

NRCA to evaluate condition and trends in the monument’s vegetation. 

Table 7. Vegetation indicators and the ecological conditions for which they apply.

Indicator Conditions tracked

Cheatgrass Vegetation conversion to cheatgrass/loss of sagebrush and woodlands

Other Invasives Vegetation/ecosystem transformation

Juniper Sagebrush-steppe conversion to wooded shrublands or woodlands.

Sagebrush & woodland Loss of sagebrush and woodlands

Bunchgrass Abundance of bunchgrass

Rare plants Occurrence of rare species

Each of these indicators is strongly controlled by fire. Fire itself could be an indicator, but it would be 

necessary to describe the effects of fire separately for the indicators in Table 7. This is essentially what 

we have done below, so it would be redundant to also include fire as an indicator. 

The effects of fire on the different vegetation indicators are shown in Figure 17 a-b. This is a general 

conceptual model based on literature discussed above. The specific relationships between fire frequency 

and dynamics of different elements of vegetation need to be determined through experiments and 

monitoring at the monument. Monitoring of vegetation throughout the monument by the Klamath 

Network will be helpful in this regard. We will refer to this figure in discussing the individual indicators 

next.
62

Figure 17a. Conceptual model of general relationships between fire frequency, as measured by the fire rotation, 

and the abundance of cheatgrass, sagebrush-steppe, and woodlands at lower elevations of the monument.

Figure 17b. Conceptual model of general relationships between fire frequency, as measured by the fire rotation, 

and the abundance of cheatgrass, sagebrush-steppe, and woodlands at middle and upper elevations of Lava 

Beds.
63

4.4.4.1 Cheatgrass

Criteria

“Good” condition would be a complete lack of cheatgrass invasion. “Somewhat Concerning” would be a

low amount of cheatgrass, and “Significant Concern” would represent widespread cheatgrass cover with

abundance in a given area increasing.

Condition and Trends

The condition and trends for this indicator are both rated Significant Concern. Figure 18 shows the 

distribution and general abundance of cheatgrass in the 169 vegetation mapping plots done at the 

monument. It was found in every plot and was often one of the dominant species. Cheatgrass only 

arrived in the western Great Basin about 100 years ago, and perhaps more recently at the monument, yet 

it is now found nearly everywhere in the monument where terrestrial vegetation can grow. Moreover, 

cheatgrass overwhelmingly dominates at the northern end of the monument and in many other areas that 

have burned relatively recently. The alteration may be irreversible because there is no means of 

controlling cheatgrass and cheatgrass invasion may ensure that fires continue to burn and favor more 

cheatgrass. Nonetheless, aside from recently burned areas in lower elevations of the monument,

cheatgrass cover appears to be considerably less extensive at the monument than in many similar areas

of the Great Basin. This may be due to a past history with less human disturbance during the settlement

period (overgrazing and fire), or perhaps the volcanic substrata at the monument, climate, or other

factors. The first cattle grazing in the vicinity of the monument began around 1873. In 1910, the first

cheatgrass was reported at sheep bedding grounds in the area which is now Lava Beds National

Monument. About 1945, some of the first attempts to re-seed perennial grasses into sites infested with

cheatgrass were completed.

The trend in fire, which drives the cheatgrass invasion process, has been an increase since the onset of 

prescription burning in the 1970s (Table 6). This increase in fire has been particularly rapid in 

woodlands. All the fire in woodlands, as mapped by Erhard (1979), in recent decades has been 

prescribed (Figure 16d). Cheatgrass invasion may be slowed if prescription burning is reduced and fire 

in sagebrush-steppe and woodlands is suppressed. The current rotations of fire in both woodlands and 

sagebrush-steppe will lead to loss of woodlands and sagebrush-steppe in favor of cheatgrass (Figures 

17a-b). This may be less severe in upper and middle elevations because species that can resprout 

following fire, like bitterbrush, are more common than at lower elevations. 

Assessment Confidence and Data Gaps

High Certainty. Cheatgrass invasion and increasing dominance are obvious within the monument, at 

least at its north end. 
64

Figure 18. Location of cheatgrass in vegetation mapping plots (2009-2011) at Lava Beds National Monument. 

Cheatgrass occurred in every plot sampled (n=169).
65

4.4.4.2 Other Invasive Plant Species

Criteria

“Good” condition would be a complete lack of other invasive non-native plants. “Somewhat

Concerning” would be a low amount of invasive non-native plants, and “Significant Concern” would

represent extensive and rapidly increasing cover of multiple invasive plant species with consequent

reductions in native plant cover.

Condition and Trends

The condition and trends for this indicator are both rated Significant Concern. There are at least 63 

invasive plant species in the monument and control of most of these has not been achieved. There are 

new invasives arriving all the time from surrounding lands, which are highly disturbed. Since 2010, the 

monument has implemented a cyclic weed monitoring and treatment program within areas of high 

visitor use (roads, parking areas, trails). Roughly one-third of the monument is surveyed each year and 

37 invasive species have been documented during these surveys. Treatment priorities are based on plant 

location, abundance, and invasive potential. The following nine species are identified as high priority for 

treatment: Scotch Thistle (Onopordum acanthium) Canada Thistle (Cirsium arvense), Medusahead Rye 

(Taeniatherum caput-medusae), Bull Thistle (Cirsium vulgare). Cereal Rye (Secale cereale), Tumble 

Mustard (Sisymbrium altissimum), goat’s beard (Tragopogon dubius), prickly lettuce (Lactuca serriola), 

and common mullein (Verbascum thapsus). In 2011, sampling occurred between June 6 and June 13,

then again on June 20 and 21—the height of the flowering season for most invasive species—and 26

segments, or 65.15 road and trail kilometers, were surveyed. By descending abundance, that effort 

detected goat’s beard, sweet clover (Melilotus sp.), bull thistle, Canada thistle, and sophia (Descurainia

sophia). Table 8 shows the percentage of segments infested by each species.

There are no comprehensive sources of information on the locations and extent of invasions by nonnative plants. There are records of where control efforts have been undertaken and there are records 

from fire monitoring (FMH) plots. In addition, vegetation sampling for an ongoing vegetation mapping 

project used a relevé approach to subjectively locate plots across the range of variation in vegetation 

types. Figures 19 and 20 summarize the invasives found in these plots. None of these data were 

collected from a probability sample of the entire monument, or even of areas necessarily at highest risk 

of invasion by non-native plants. Where fire treatments have been done, those data need to be collected 

and analyzed with a Before-After Control Impact assessment (BACI: Stewart-Oaten and Bence 2001) 

analysis.
66

Figure 19. Locations of invasive plants documented at Lava Beds National Monument in 169 vegetation mapping

plots.
67

Table 8. Summary of prioritized invasive species early-detection monitoring at Lava Beds NM. Note: an * 

indicates species surveyed only in wilderness areas.

Scientific Name Total # of Infestations

# of Segments 

Infested % of Segments Infested

Descurainia sophia* 31 7 26.92

Tragopogon dubius* 29 10 38.46

Melilotus sp. 6 3 11.54

Cirsium vulgare 2 2 7.69

Cirsium arvense 1 1 3.85
68

Figure 20. Locations of invasive plant species recorded in FY 2011 Invasive Species Early Detection 

monitoring by the Klamath Network. The circle size denotes the size of the infestation.

Invasions by sophia (Descurainia sophia) often coincide with locations that have been most

invaded by cheatgrass. The growth of Descurainia may in part come at the expense of cheatgrass

or vice-versa, although we are not aware of research on this. Most all other infestations are small 

individual locations, and it does not appear that any of these species are in the process of 

transforming ecosystems. Nonetheless, caution to avoid underestimating invasive plants is 
69

particularly warranted in an environment like Lava Beds. Nearby lands are managed by the US 

Forest Service, which conducts widespread fuel treatments; these treatments have been found to 

promote invasives (Stephens et al. 2012). Impacts by non-native invasives other than cheatgrass 

may seem subordinate in comparison to cheatgrass, but they are still potentially very significant 

concerns. 

In general, it can be assumed there are ever increasing numbers of potential invaders. If more fire 

occurs due to cheatgrass growth, climate change or other factors, invasions will follow. 

However, these invasions are unlikely to add much to the degradation that is already being 

caused by cheatgrass.

Assessment Confidence and Data Gaps

Medium Certainty. More remote areas of the monument that are not traversed by trails were

poorly sampled by most previous vegetation surveys. However, these areas are less likely to be

invaded. There is a need for comprehensive monitoring of all burn areas and mechanically 

disturbed areas, if there are any, and appropriate statistical analysis of the data. Ideally, an early

detection program for prioritized species that are not already well established (Table 8) could be

implemented within fire management. Such a program should be designed to feed into rapid

response control programs and adaptive management as shown in Figure 21. There are no

specific data on invasive plant species’ trends in Lava Beds National Monument.

Figure 21. Conceptual model of an invasive species early detection program and the feedbacks with

management (From Odion et al. 2010).
70

4.4.4.3 Juniper

Criteria

“Good” condition would be a complete lack of increased juniper growth where juniper conflicts 

with other critical resource management goals. “Somewhat Concerning” condition would be a

low amount and “Significant Concern” would represent extensive and rapidly increasing juniper

growth leading to substantial changes that compromise chosen ecosystem-level management 

goals. A specific quantitative amount of juniper growth that would constitute a significant 

concern is not possible to identify due to uncertainty in reference conditions and because of sitespecific considerations. It is also important to note that excess juniper growth is a cultural 

resource management issue. The monument has a management mandate to maintain the visual 

abundance of juniper at levels like those at the time of the Modoc Indian war. Were this not the 

case, juniper growth may not be as much a cause for concern.

Condition and Trends

Somewhat Concerning. Photos show the southern end of Lava Beds National Monument to be

lacking in juniper around the time of the Modoc Indian War in the 1870s or not long after. 

Juniper is now widely scattered in this area and visually quite apparent, but there are no recent 

data on trends in juniper cover throughout the monument. Such an analysis may be possible with 

historical aerial photography. LANDSAT imagery is of limited utility for calculating trends 

because it covers a relatively short time span. Juniper may also be less abundant and less 

ecologically impacting than it appears because it is extremely conspicuous, even at low levels of 

abundance. 

Active management to reduce juniper cover in areas where it is increasing began in 2007 with

the removal of junipers over 1200 acres at the northern end of the monument, and can slow the 

spread of juniper if this is desired. In the past, juniper abundance fluctuated naturally with 

climate in ways that are poorly understood, and its current dynamics are not necessarily related 

to controllable human actions (Romme et al. 2009). In addition, the amount of fire in woodlands 

and sagebrush-steppe (Table 6) where juniper is increasing is likely to result in future reduction 

in juniper. 

Assessment Confidence and Data Gaps

Medium Certainty. Some expansion of juniper cover in the monument during the last century is 

apparent, but there is much uncertainty regarding past, present, and future dynamics of juniper.

Monitoring by the Klamath Network will help considerably to fill this data gap. Future analysis 

and synthesis reports concerning vegetation monitoring findings will also evaluate the latest 

literature and ecological implications of any vegetation trends detected. This should be very 

helpful to monument management goals for juniper.

4.4.4.4 Sagebrush Steppe and Woodlands

Criteria

“Good” condition would be maintenance of a characteristic amount of sagebrush-steppe and

woodlands. “Somewhat Concerning” and “Significant Concern” would represent increasingly

greater loss of sagebrush-steppe and woodlands with consequent compromise of chosen goals for

overall ecosystem management.
71

Condition and Trends

Significant Concern. Although quantitative data are lacking, a decline in sagebrush cover in the 

monument over the last century is apparent. Paralleling this decline is the documented 

disappearance from the monument of historical populations of the sagebrush-dependent greater 

sage-grouse, and possibly the decline of other sagebrush-dependent birds. Future loss of firesensitive sagebrush cover may be unavoidable because fires are inevitable, and fires (whether 

prescription or wild) are followed by invading cheatgrass, especially at lower elevations. 

Assessment Confidence and Data Gaps

Medium Certainty. The cover of sagebrush has clearly diminished within the monument, but the 

exact areas and rate of decline are unmeasured. It is well known that sagebrush steppe and

woodlands are sensitive to fire, and that fire at most locations within the monument will lead to

more cheatgrass, more fire, and less sagebrush in a self-reinforcing cycle. Monitoring by the 

Klamath Network will help considerably to fill data gaps regarding changes in sagebrush-steppe. 

Future analysis and synthesis reports of vegetation monitoring findings will also evaluate the 

latest literature and ecological implications of any vegetation trends detected. This should be 

very helpful to monument management of sagebrush-steppe.

4.4.4.5 Bunchgrasses

Criteria

“Good” condition would be maintenance of a characteristic amount of bunchgrasses. “Somewhat

Concerning” and “Significant Concern” would represent increasingly greater displacement of

bunchgrasses by invasive non-native plants.

Condition and Trends

The condition and trends for this indicator are both rated Somewhat Concerning. The prohibition 

on grazing and the ongoing occurrence of large amounts of fire is favorable to more bunchgrass 

cover, particularly in the mid-elevations where bunchgrasses may be somewhat limited by shade, 

for example, in the understory of juniper. In fact, if amounts of fire are uncharacteristically high, 

fire could create amounts of bunchgrasses that are also uncharacteristically high. However, 

bunchgrasses in burned areas at lower elevations must coexist with potentially dense cover of 

cheatgrass, which will likely reduce the amount of bunchgrasses. 

Assessment Confidence and Data Gaps

Medium Certainty. Trends in bunchgrasses within the monument are unmeasured, but based on 

limited knowledge of plant community dynamics and past fires, some decline can be assumed. 

Little is known about the long-term dynamics between bunchgrasses and cheatgrass, in

particular, the long-term recruitment and mortality rates of the bunchgrasses and the impacts of

climate change. Because bunchgrasses have been displaced much more by cheatgrass at lower

elevations, it is likely that bunchgrasses will be more negatively affected in drier environments in 

general, which is consistent with the susceptibility of Great Basin vegetation to invasion by 

cheatgrass being higher at lower elevations where bunchgrasses are less common (Chambers et 

al. 2007). At Lava Beds, more fire also appears to be occurring at lower elevations. Monitoring 

by the Klamath Network will help considerably to fill data gaps regarding changes in 

bunchgrasses. There is also research by Eva Strand, University of Idaho, on bunchgrass 

abundance that may help elucidate trends. Future analysis and synthesis reports of vegetation 
72

monitoring findings will also evaluate the latest literature and ecological implications of any 

vegetation trends detected. This should be very helpful to monument management of 

bunchgrasses.

4.4.4.6 Rare Plants and Diversity of Native Plant Species

Rare plants contribute disproportionately to regional diversity. However, analyses of statistical

power and other issues have shown that rare plants are impractical to use as ecological indicators

(Manley 2004, Sarr et al. 2007). Thus, the policy of the Klamath Network has been to avoid

focusing on just rare species and instead to sample all vegetation. Diversity patterns (i.e., 

composition) within communities of vegetation are a key component of this vital sign.

Criteria

“Good” condition would be represented by the sustaining of naturally-occurring turnover rates of

all native plant species currently inhabiting the monument. This includes sustaining

metapopulations and gene pool diversity. “Somewhat Concerning” and “Significant Concern”

would represent increasingly high turnover rates of all native plant species currently inhabiting

the monument.

Condition and Trends

Indeterminate. None of the monument’s plants are federally listed as threatened or endangered, 

and no species is endemic to the monument. However, Erhard (1979) describes a distinctive

plant association—purple sage and fernbush scrub (Salvia dorrii and Chamaebatiaria sp.)—

which he considered to be endemic. Eight plants occurring within the monument or just outside

the monument’s boundary are listed by the California Native Plant Society (CNPS) as species of 

concern (Table 9). Two have never been collected within the monument: Hulsea nana was 

collected from Cinder Butte, just south of the monument, and Iliamna bakeri was collected just

south of the monument. The other six have all been collected within the monument. Penstemon

cinereus was collected long ago from the monument but it is currently considered to be a minor

variant of the more widespread Penstemon humilis var. humilis. Thus, of the eight plants listed in 

Table 9 only five are currently found within the monument boundary. Among these species,

Salvia dorrii might be threatened by too-frequent fire. The monument contains a single grove of

quaking aspen, a tree species renowned as wildlife habitat. It is located near Heppe ice cave, and 

was partially burned during the Big Nasty prescribed fire of 2007. Resprouting trees are being

monitored.

Trends in the monument’s rare plant species are unknown. Whether some species have been

extirpated from the monument is impossible to say, partly because the exact locations of many

historically-reported species were not described, at least not with the precision currently

available with GPS. There is no particular reason to assume that any species that occurred in the 

monument has been extirpated from the monument.

Assessment Confidence and Data Gaps

Although the monument’s flora has been relatively well inventoried, no permanent plots or

transects representing a probabilistic sample of plant communities in the monument have been

monitored over time. However, the Klamath Network established 40 permanent monitoring plots 

in 2012 and collected the first year of data. These plots will be resampled every three years. 

Additional efforts will be needed to capture trends in rare plants. 
73

Table 9. Rare plants listed by the California Native Plant Society (CNPS) from Lava Beds National 

Monument or the immediate vicinity (from Smith 2009). 

Species Name

Global

Rank1

State 

Rank2 CNPS List3

Vouchered from 

monument

Dimeresia howellii G4? S2.3 2.3 Y

Erigeron elegantulus G4G5 S3.3 4.3 Y

Hackelia cusickii G5? S3.3 4.3 Y

Hulsea nana G4 S2.3 2.3 N

Iliamna bakeri G4 S3.2 4.2 N

Penstemon cinereus G4 S3.3 4.3 Y

Rorippa columbiae G3 S1.1 1B.2 Y

Salvia dorrii var. incana G5T5 S1S2 3 Y

1

Global Ranking

The global rank (G-rank) reflects the overall condition of an element throughout its global range.

Species or Community Level

G4 = Apparently secure but factors exist to cause some concern; i.e., there is some threat, or somewhat

narrow habitat; G5 = Population or stand demonstrably secure to ineradicable due to being commonly

found in the world.

Subspecies Level

Subspecies receive a T-rank attached to the G-rank. The T-rank reflects the global situation of just the

subspecies or variety.

2

State Ranking

The state rank (S-rank) is assigned much the same way as the global rank, except state ranks in

California often also contain a threat designation attached to the S-rank.

S1 = fewer than 6 EOs or fewer than 1,000 individuals or less than 2,000 acres; S1.1 = very threatened;

S1.2 = threatened; S1.3 = no current threats known; S2 = 6-20 EOs or 1,000-3,000 individuals or 2,000-

10,000 acres; S2.1 = very threatened; S2.2 = threatened; S2.3 = no current threats known; S3 = 21-80

EOs or 3,000-10,000 individuals or 10,000-50,000 acres; S3.1 = very threatened; S3.2 = threatened; S3.3

= no current threats known.

3

CNPS Ranking

1B = Rare or Endangered in CA and elsewhere; 2 = Rare and Endangered in CA, more common 

elsewhere; 3 = Need more information; 4 = Plants of Limited Distribution. The extension is added to the 

List rank following a decimal point: .1 = Seriously endangered in CA; .2 = Fairly endangered in CA; .3 = 

Not very endangered in CA.
74

4.5 Changes in Aboveground Wildlife

4.5.1 Background

As used herein, “aboveground wildlife” refers to terrestrial vertebrates and invertebrates, and 

excludes strongly cave-dependent species such as bats. The opportunity to observe wildlife in

natural settings is an important reason why many people visit parks. Moreover, wildlife species

serve vital ecological roles, such as pollinators, nutrient cyclers, and seed transporters.

The monument spans three very different habitats—ponderosa pine forest, juniper-mountain 

mahogany shrub, and sagebrush-bunchgrass steppe. Consequently, it supports a fair variety of 

aboveground wildlife species. The number of species is limited by the near-absence of surface 

water; as noted earlier, the monument has no permanent ponds, lakes, streams, or wetlands. 

However, some of the larger, more mobile, and less water-dependent birds and mammals 

undoubtedly move regularly between the monument and wetlands of the nearby Tule Lake

National Wildlife Refuge. Only a small percentage of the monument’s hundreds of wildlife 

species inhabit cave environments, but many others obtain water at the mouths of caves or from 

melting ice a short distance within. No vertebrates are endemic to the monument. Neither the 

monument nor any inland areas at similar elevation and within several dozen miles comprises the 

northern boundary of any vertebrate’s geographic range in western North America. 

4.5.2 Regional Context

As well as providing the most extensive habitat for cave-dwelling species for hundreds of miles 

around, the monument provides some of the most extensive ungrazed grassland and shrub steppe 

for dozens of miles around. Thus, it may serve as a source for colonizing individuals as they 

disperse into fragments of somewhat less suitable habitat in the surrounding area.

4.5.3 Issues Description

4.5.3.1 Fires and Natural Succession

Throughout much of the West, decades of active fire suppression have dramatically altered 

vegetation and thus wildlife species composition. However, the opposite may be the case within 

this monument’s boundaries. Here, the incidence of fires appears to have increased from 

historical levels in the woodland and sagebrush areas. The high incidence of relatively recent 

fires may have been facilitated (and caused) by the early establishment and rapid spread of 

highly flammable cheatgrass. This has been accompanied by a decline within the monument (and 

region) of sagebrush and perhaps mountain mahogany. Overall, wildlife species richness would 

be expected to increase with increasing cover of bunchgrasses, sagebrush, and juniper, but 

decrease with increasing cover of cheatgrass. 

Effects of prescribed fire in ponderosa pine stands at the monument were studied by the Klamath 

Bird Observatory, 2002-2004. In both the spring and fall, prescribed fire did not influence the 

average number of bird species detected per monitoring site. More total bird species were 

observed on the burned area in both years following the fire than the year before the fire. A 

concern has been expressed that large-diameter ponderosa pines which currently provide roosts 

for wintering bald eagles are not being replaced rapidly enough by new growth (Stohlgren 1993, 

Stohlgren and Farmer 1994).
75

4.5.3.2 Climate Change

An analysis of the vulnerabilities of California nesting birds to climate change was published by 

Gardali et al. (2012). Of 128 species they identified as most vulnerable, those which are likely to 

have formerly or currently nested in the monument are:

• Swainson’s hawk

• greater sage-grouse

• mountain quail

• ruffed grouse

• sooty (blue) grouse

• northern saw-whet owl

• common nighthawk

• common poorwill

• rufous hummingbird

• bank swallow

• juniper titmouse

• Brewer’s sparrow

• red crossbill

4.5.3.3 Contaminants

Contaminants in the monument’s bats have been measured but no data were made available for 

this report, and effects are unknown. Contaminants such as mercury and persistent pesticides are

a potential concern because of aerial transport of contaminants into the monument from distant

areas. Besides bats, aerial foragers likely to be at greatest risk are swallows and common 

nighthawk. Just outside the monument on agricultural lease lands of the Klamath National 

Wildlife Refuge, over 50 different pesticides are used. Hatchling success there was found to be 

lower in areas treated repeatedly with fungicides. Analyses of dietary items determined that 

nestlings were exposed to the pesticides dicamba and 2,4-D herbicides, which are approved for 

refuge use, and also to aldicarb, carbofuran, propazine, simazine, and dichlorprop, which are not 

approved for refuge use (Hawkes and Haas 2005). 

Subsequently, the U.S. Fish and Wildlife Service (2007) issued a programmatic Biological

Opinion that considered the risks of pesticides to suckers (fish) and bald eagles in the Klamath 

Basin. Based on the limited existing data on pesticide impacts and distribution, pesticide use

information, benchmark toxicity values, and habitat use of the threatened and endangered

species, the Biological Opinion evaluated impacts from direct exposure to the organisms, indirect

effects through pesticide-induced reduction in prey populations, and pesticide-induced reductions

in water quality. Although the assessment found that some level of pesticide exposure could

occur to these two species, the evidence did not support a determination that the pesticide

applications were likely to harm populations of these species. 

4.5.3.4 Human Disturbance and Non-native Wildlife

Some wildlife species, including many avian nest predators (e.g., jays, raven, squirrels) are

attracted to congregations of people such as at campgrounds, scenic pullouts, and picnic areas. 

Resulting increases in nest predation can have detrimental effects on local populations of other 
76

species, particularly on songbirds. Whether this is the case at Lava Beds has not been 

determined, but the possibility of such impacts is plausible. Christmas Bird Count data from the 

vicinity of the monument indicate a statistically significant 28-year increase in numbers of 

ravens (Table 10). 

Some wildlife species are exceptionally sensitive to human presence. If humans approach too 

closely during critical nesting periods, they abandon nests and leave eggs exposed to predators 

and excessive heat. Among the more sensitive species are several uncommon raptors that nest 

within the monument, such as Swainson’s hawk, short-eared owl, prairie and peregrine falcons, 

and bald and golden eagles (Dixon and Bond 1937, Bond 1939). During winter, roosts of the 

bald eagles that congregate in the ponderosa forest near the southern end of the monument are 

potentially very sensitive to disturbance (Keister and Anthony 1983; Keister et al. 1985, 1987). 

In parts of the monument, illegal poaching of mule deer has been noted. The prohibition against

hunting within the monument causes individual deer to acclimate to humans and makes them 

easy targets for poachers.

Non-native bird species reported from the monument include European starling, house sparrow, 

wild turkey, and a recent invader of adjoining agricultural lands: Eurasian collared dove. Small 

numbers of domestic sheep also range into the monument. The effects, if any, of these species on 

the native fauna are unknown.

4.5.3.5 Habitat Fragmentation

When the home ranges of some species are interrupted by roads and other cleared areas, the 

habitats are fragmented. Individuals in fragmented habitats are often subjected to greater

predation, even in rangeland settings (Knick and Rotenberry 2002, Vander Haegen 2007), and 

feeding and reproductive attributes (e.g., genetic isolation) can be interrupted. Roads and traffic

result in more road killed animals, and in extreme cases, noise associated with roads degrades

reproductive success of some species. To some degree, wildlife corridors (usually, unaltered

bands of natural vegetation that connect larger patches and so create “connectivity”) can lessen

fragmentation impacts on wildlife, as can management practices within the cleared areas that

leave relicts of the original vegetation structure. Connectivity and fragmentation are perceived

differently by different species. Functional connectivity of habitat for one species (e.g., deer,

cougar) is not necessarily recognized by other species (snakes, plants). Connectivity can also be

provided by some types of broad habitat “mosaics” (not continuous bands) over large, relatively

natural areas, or as stepping stones comprised of suitable habitat patches.

4.5.4 Indicators and Criteria to Evaluate Condition and Trends

Two indicators that might be used to monitor this issue (Changes in Wildlife) are:

1. Diversity of Native Terrestrial Wildlife Species, including Rare Species

2. Extent and Connectivity of Important Terrestrial Habitats

The monument maintains a wildlife observations database, containing records from 1943 to 

present. Appendix D summarizes its data by species for all vertebrates. The data were not 

collected systematically and quality of some observations is unknown, so only limited inferences 

can be made.
77

4.5.4.1 Diversity of Native Terrestrial Wildlife Species, Including Rare Species

Meaningful criteria for evaluating this indicator would need to account for the natural range of

variation in species colonization and extirpation, and the expected annual fluctuations in

population levels. However, data for estimating these are not generally available from the

monument or from analogous areas nearby. As well, there are no legally-based numeric criteria

for evaluating the degree of “intactness” of any of the monument’s wildlife communities. No

agency, institution, or scientific researcher has defined minimum viable population levels,

desired productivity or species richness levels, or other biological criteria relevant to any wildlife

species in this particular park. Therefore, the assessment of this indicator is based mainly on

professional judgment of the authors.

For purposes of this assessment, “Good” conditions would be represented by the sustaining of

naturally-occurring turnover rates of all native terrestrial species currently inhabiting a park. This

could include intentionally re-establishing those species which were extirpated but have the

potential to become re-established. More detailed goals might be to sustain multiple

representatives of each functional group in proportions characteristic of intact but dynamic

ecosystems and well-functioning complex food webs, as well as sustaining metapopulations and

gene pool diversity. “Somewhat Concerning” and “Significant Concern” ratings would be

assigned depending on the degree to which species turnover rates and/or terrestrial biodiversity

are likely to affect adversely the rates of important ecosystem functions.

Condition and Trends

These vary by species, but overall we assign a rating of Somewhat Concerning – Low Certainty 

for condition and Indeterminate for trends. A higher rating of “Good” is not assigned due to the 

decline or loss of breeding populations within the monument of greater sage-grouse and possibly 

other sage-associated birds. A rating of “Significant Concern” is not assigned due to the lack of

any evidence of recent extirpations of native wildlife species from the monument. No systematic

long term data are available on trends of any of the monument’s wildlife species. For many miles 

around, the monument provides the only or best habitat for American pika and several species of 

bats.

4.5.4.1.1 Ungulates, Omnivores, and Predatory Mammals

The monument’s most common ungulate is mule deer, and the monument provides preferred 

winter habitat. The only population estimate for the monument is from the 1970s, when 

wintering deer numbers were estimated at 1500-2000 (Schnoes 1978). During some winters,

snow depth at the upper elevations of the Medicine Lake Highlands forces the deer to move

down the eastern slope and into the monument (Ashcraft 1961). At that time many individuals 

join herds along Hill Road at the north end of the monument, attracted by the farm fields and

water of the Tulelake basin. Research within the monument indicated that individual deer use the 

same area (home range) each winter. During at least some winters, deer distribution is affected 

more by availability of cover than by food. Within the monument, bitterbrush is a preferred 

winter food; during winter individual deer range over about 1.1 km in the southern part of the 

monument and 3.1 km in the northern part (Schnoes 1978). 

Small numbers of pronghorn are also present in the grassy northern part of the monument. 

According to the monument’s wildlife observations database, this is the third-most frequently 

reported mammal, with 357 sightings as of July 2012, and is exceeded only by sightings of mule 
78

deer (442) and coyote (403); see Appendix D. The wildlife observations database indicates that

elk (wapiti) were reported on six occasions between June 2006 and February 2010.

Mountain bighorn sheep, which had been present in the monument historically, were reintroduced in 1971. A small population was established but all individuals succumbed to 

pneumonia during 1980, possibly infected by domestic sheep from adjoining areas (Foreyt and 

Jessup 1982).

Based on the wildlife observations database, it appears that black bears are rare in the 

monument, with only 11 sightings reported between 1985 and 2005. Far more common are 

records of bobcat (351 sightings) and cougar (166). Sightings of cougar within the monument 

seem to have increased in recent years (Horney 2008). In California, an area of at least 850

square miles (2200 sq km) may be required for a cougar population to remain stable or increase

over time (Dickson and Beier 2002). The monument is only 2% of that area, so local cougars 

must forage as well over large areas outside the monument.

As shown in Appendix D, other predatory or omnivorous mammals reported in the monument’s 

wildlife observations database include:

• long-tailed weasel (61 sightings)

• American badger (56)

• raccoon (33)

• striped skunk (23)

• gray fox (19)

• spotted skunk (11)

• short-tailed weasel (8)

• red fox (7)

American badger is considered a “Species of Special Concern” by the California Department of 

Fish and Wildlife.

4.5.4.1.2 Other Mammals

American pika is a rabbit-relative that is believed to be disappearing in many areas of the West

(Beever et al. 2003). Normally a mountain-dweller, the species is also found regularly in barren

lava landscapes (Rodhouse et al. 2010). Although its occurrence is influenced by many factors, it 

is considered an indicator species for detecting ecological effects of climate change. In the 

summers of 2010 and 2011, randomly-selected sites within the monument were searched for

evidence of pika occupancy. Of these, 29 (29%) were considered occupied in 2011. Of the 2010

sites that were resurveyed in 2011 (n=42), five sites were colonized and seven previously

occupied sites were unoccupied. Occupied sites were found on all of the major lava flows

surveyed in both years, including the Callahan, Devil’s Homestead, and Schonchin flows. Using 

techniques described in the NPS standard protocol (Jeffress et al. 2011), these sites will be

monitored over time to detect trends in pika site occupancy.

As shown in Appendix D, reports from the monument’s wildlife observations database of other 

aboveground mammals include, most often: 
79

• porcupine (179 sightings)

• yellow-bellied marmot (132)

• mountain cottontail (83)

• black-tailed jackrabbit (81)

• California ground squirrel (53) 

Excluding bats, a total of 36 mammal species are officially listed as occurring in the monument. 

Aboveground mammals that are included on the official monument list but have no records in 

the wildlife observations database are mink, muskrat, and mountain vole. Systematic surveys of 

small mammals are limited to one survey done for the NPS in 2002. At that time, the species 

caught most often was the yellow-pine chipmunk (52% of 164 captures in 600 trap nights). 

4.5.4.1.3 Birds

The bird species that are present in the monument are a subset of all bird species in the general 

area, all of which are known to breed within the surrounding area/Klamath Basin. However, for 

many species, the monument likely provides nesting habitat of much better quality than occurs in 

surrounding areas. The official monument bird list includes many species that have never been 

recorded in the monument’s wildlife observations database and are unlikely to occur within the 

monument; e.g., least bittern. Conversely, some birds in the observations database are not shown 

on the monument’s official bird list. In 2006 the Klamath Bird Observatory established 25

permanent point count survey routes, each consisting of 12 survey points, and is monitoring birds 

every three years. Data have not yet been summarized. No annual breeding bird survey routes 

have been run near the monument.

The Tulelake Christmas Bird Count (CBC) has been conducted by volunteers on one day 

annually since 1987 and includes part of the monument in its 15-mile diameter circle (Figure 22). 

Trends in numbers of songbird and raptor species from the entire count circle were analyzed and 

are shown in Table 10. Based on statistical significance of trend as determined by the MannKendall test, numbers of 14 species declined and 15 increased significantly. Many of the species 

that declined are raptors. Neither species richness (the number of species) nor abundance (the 

summed individuals of all species) showed a significant trend. CBC counts do not have a tightly 

standardized protocol, and the number of observers, hours spent, areas covered, and weather all 

vary from year to year with uncertain effects on apparent bird trends.
80

Table 10. Trends in selected wintering and resident songbirds and raptors in the Tulelake Christmas Bird

Count, 1987-2011.

Note: Species are listed in order from most negative to most positive 28-year trend. Lava Beds National 

Monument comprises 18% of the Count circle (22), and the portion of each species’ data that were from 

Lava Beds in any given year is unknown. The level of effort, expertise of observers, and exact areas 

surveyed within the 15-mile diameter count circle vary from year to year. This suggests caution in 

interpreting apparent trends. Water-associated species and species found fewer than four years were 

excluded.

Species Name

Maximum 

per Year

# of Years 

Reported

Trend

(Z-statistic)

Statistical 

Significance

California Towhee 32 28 -4.49 ***

American Tree Sparrow 31 21 -4.00 ***

Bald Eagle 451 27 -3.95 ***

Northern Harrier 627 28 -3.44 ***

Ring-necked Pheasant 1192 28 -3.05 **

Sage Thrasher 28 21 -2.88 **

Rough-legged Hawk 250 28 -2.81 **

Golden Eagle 12 25 -2.81 **

Red-tailed Hawk 269 28 -2.55 *

Hairy Woodpecker 2 12 -2.47 *

House Finch 1233 28 -2.23 *

Northern Shrike 8 25 -2.20 *

Short-eared Owl 7 24 -2.08 *

Pinyon Jay 71 8 -1.97 *

California Quail 848 28 -1.64

Ferruginous Hawk 5 16 -1.49

Evening Grosbeak 45 11 -1.47

Red-breasted Sapsucker 3 17 -1.06

Bohemian Waxwing 17 4 -0.95

Townsend's Solitaire 74 28 -0.89

Cedar Waxwing 53 9 -0.81

Canyon Wren 34 27 -0.78
81

Table 10 (continued). Trends in selected wintering and resident songbirds and raptors in the Tulelake

Christmas Bird Count, 1987-2011.

Note: Species are listed in order from most negative to most positive 28-year trend. Lava Beds National 

Monument comprises 18% of the Count circle (22), and the portion of each species’ data that were from 

Lava Beds in any given year is unknown. The level of effort, expertise of observers, and exact areas 

surveyed within the 15-mile diameter count circle vary from year to year. This suggests caution in 

interpreting apparent trends. Water-associated species and species found fewer than four years were 

excluded.

Species Name

Maximum 

per Year

# of Years 

Reported

Trend

(Z-statistic)

Statistical 

Significance

Lapland Longspur 290 18 -0.77

White-crowned Sparrow 729 28 -0.73

Downy Woodpecker 2 12 -0.72

Mountain Bluebird 543 18 -0.67

Prairie Falcon 15 28 -0.28

Brown-headed Cowbird 61 19 -0.20

Bushtit 93 20 -0.04

American Robin 9771 28 0.00

Loggerhead Shrike 14 28 0.06

Mountain Chickadee 24 17 0.06

Dark-eyed Junco 1484 28 0.12

Titmouse sp. (prob.

Juniper) 16 26 0.14

Barn Owl 12 26 0.16

Song Sparrow 1073 28 0.20

Black-billed Magpie 54 28 0.26

White-breasted Nuthatch 1 4 0.30

Bewick's Wren 56 28 0.71

White-throated Sparrow 2 7 0.74

Golden-crowned Sparrow 99 28 0.87

Horned Lark 4380 27 0.91

Savannah Sparrow 47 18 0.91

Ruby-crowned Kinglet 3 9 1.01

Sharp-shinned Hawk 2 8 1.06
82

Table 10 (continued). Trends in selected wintering and resident songbirds and raptors in the Tulelake

Christmas Bird Count, 1987-2011.

Note: Species are listed in order from most negative to most positive 28-year trend. Lava Beds National 

Monument comprises 18% of the Count circle (22), and the portion of each species’ data that were from 

Lava Beds in any given year is unknown. The level of effort, expertise of observers, and exact areas 

surveyed within the 15-mile diameter count circle vary from year to year. This suggests caution in 

interpreting apparent trends. Water-associated species and species found fewer than four years were 

excluded.

Species Name

Maximum 

per Year

# of Years 

Reported

Trend

(Z-statistic)

Statistical 

Significance

American Kestrel 39 28 1.13

Golden-crowned Kinglet 27 22 1.32

American Pipit 25 9 1.46

Hermit Thrush 8 13 1.50

Great Horned Owl 22 28 1.51

Spotted Towhee 12 28 1.64

American Goldfinch 27 12 1.72 *

Western Bluebird 18 3 1.85 *

Western Scrub-Jay 7 22 1.85 *

Merlin 4 22 1.89 *

Northern Flicker 41 28 1.90 *

Common Raven 118 28 2.04 *

Varied Thrush 4 4 2.07 *

Western Meadowlark 1089 28 2.07 *

Rock Wren 11 19 2.23 *

Lesser Goldfinch 70 22 2.27 *

European Starling 1228 28 2.51 *

Brewer's Blackbird 3652 28 2.67 **

Mourning Dove 149 21 2.75 **

Red-shouldered Hawk 1 4 3.12 **

Eurasian Collared-Dove 249 4 3.23 **

* trend with statistical significance

** trend with high statistical significance 

*** trend with very high statistical significance
83

Figure 22. Boundaries of the Tulelake Christmas Bird Count circle, relative to Lava Beds National 

Monument.

Two raptors that nest in the monument—bald eagle and peregrine falcon—were formerly listed 

as federal endangered species but have since been removed from the list due to increasing 

populations nationwide. Both are still listed as endangered by the State of California. Stands of 

large conifers in the southern part of the monument (Caldwell/Cougar Butte and Eagle Nest

Butte) provide key roosting habitat for bald eagles wintering throughout the Klamath Basin

(Stohlgren 1993, Stohlgren and Farmer 1994). Numbers of eagles leaving the roosts annually 

have been counted annually since 1987 but data apparently have not been published or entered in 

a computer database for analysis.

The California Department of Fish and Wildlife (CDFW) has designated two other Lava Bed 

species—Swainson’s hawk and bank swallow—as threatened statewide, and has designated 

great gray owl as endangered. Swainson’s hawk forages sporadically in grasslands of the 

northern part and after a long absence, attempted to nest in 2011. Bank swallow has been 

reported only three times, the most recent in 1972, and its current nesting status in the monument 

is uncertain. The owl has been reported only once, in August 1992. If nesting at all, it is most 

likely to be found in ponderosa forest. 
84

The CDFW has also designated several species as Species of Concern statewide due to known or 

suspected declining trends in populations or habitat statewide. These include the following, some 

of which may nest within the monument:

• greater sage-grouse (31 sightings since 1943 reported in the monument’s wildlife 

observations database)

• northern goshawk (17 sightings)

• northern harrier (35 sightings)

• short-eared owl (32 sightings)

• long-eared owl (2 sightings)

• burrowing owl (14 sightings)

• long-billed curlew (3 sightings)

• Vaux’s swift (2 sightings)

• olive-sided flycatcher (3 sightings)

• loggerhead shrike (41 sightings)

• purple martin (63 sightings)

• yellow warbler (24 sightings)

The US Fish and Wildlife Service has designated as Birds of Conservation Concern the 

following additional species, which may (or do) nest within the monument: 

• golden eagle (89 sightings)

• prairie falcon (119 sightings)

• flammulated owl (2 sightings)

• rufous hummingbird (24 sightings)

• Allen’s hummingbird (5 sightings)

• Lewis’s woodpecker (57 sightings)

• white-headed woodpecker (9 sightings)

• black-chinned sparrow (2 sightings)

• Brewer’s sparrow (2 sightings)

The USDA Forest Service, in the Modoc National Forest just to the south of the monument, has 

highlighted the following bird species—also present and possibly nesting at Lava Beds—as 

Management Indicator Species (MIS), with the implication that if their numbers decline, that 

may in some cases indicate that management practices are causing harm. In addition to sage 

grouse and yellow warbler already listed above, they are: sooty/blue grouse (35 sightings since 

1943 reported in the monument’s wildlife observations database), hairy woodpecker (9

sightings), and mountain quail (41 sightings).

Of the species on the monument’s bird list, one that has perhaps drawn the most attention is the 

greater sage-grouse. That is because it has declined dramatically throughout nearly all of its 

continental range, and has declined dramatically in northern California since the 1950s. It is 

currently designated as a federal Species of Special Concern, and is being considered for federal 

listing as Threatened. It probably was once common at Lava Beds, but with the exception of 
85

unconfirmed sightings near Hovey Point as recently as September 2008, it has not been 

confirmed nesting within the monument since the late 1970s (Horney 2008). Its decline in 

northern California outside of the monument has been attributed directly to fragmentation and

loss of sagebrush habitat, and indirectly to loss of sagebrush through fire and grazing, invasion of

cheatgrass, increasing cover of shading juniper, and lowering of water tables. The nearest

remaining active lek (breeding site) and known rearing areas are located around Clear Lake

National Wildlife Refuge, about 15 miles east of the monument. In 2008 the grouse population 

there was estimated at fewer than 50 individuals and was not considered viable (Horney 2008). A 

recovery plan for grouse in this area and extending westward to Lava Beds and beyond was 

drafted by resource agencies, including the National Park Service. The monument comprises 

about 18% of the approximately 254,000 acres covered by the plan (Horney 2008). Reintroducing the grouse to Lava Beds is being actively considered, and monument personnel are 

selectively reducing juniper cover to enhance future habitat for this species. 

Other bird species that regularly breed in sagebrush-juniper habitats of northern California 

(California Partners in Flight 2005), listed in order of their frequency of records from any time of 

year in the monument’s wildlife observations database, include:

• loggerhead shrike (41 sightings)

• western meadowlark (17 sightings)

• sage thrasher (16 sightings, last reported in 2004)

• lark sparrow (11 sightings)

• green-tailed towhee (10 sightings)

• vesper sparrow (6 sightings)

• gray flycatcher (2 sightings)

• Brewer’s sparrow (2 sightings, last reported in 1962)

• juniper titmouse (no reports in database but reported by Klamath Bird Observatory)

• sage sparrow (no reports)

Based on the KBO surveys and wildlife observations database, it appears likely that sage 

sparrow has been extirpated from the monument as a nesting species coincident with the 

fragmentation and decline of sagebrush cover in northern California generally, and there 

apparently has been only one (Stephens et al. 2009) recent detection of sage thrasher. 

4.5.4.1.4 Reptiles and Amphibians

There are reports of 14 species of reptiles in the monument’s wildlife observations database since 

1943. Two of these are not on the official monument list: western whiptail (one report in 1993) 

and racer (27 reports). 

The monument’s amphibian richness is very low compared with equal-sized areas of California, 

but this is expected given the lack of surface water required for breeding. The only documented 

species are western (boreal) toad and Pacific treefrog. Pacific treefrog is found near the 

entrances of many of the monument’s caves. In addition, the wildlife observations database lists 

one record each for rough-skinned newt and foothill yellow-legged frog. 
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4.5.4.1.5 Terrestrial Invertebrates

No systematic, monument-wide inventories of terrestrial invertebrates have been conducted. 

However, informal surveys of butterflies have been conducted since 2009, resulting in a list of 

over 50 species. Management practices intended to maintain butterfly habitat are implemented 

along the shoulders of the monument’s roads.

Condition and Trends

Assessment Confidence and Data Gaps

Low Certainty. Although the monument maintains a wildlife observations database, those data

are not systematic or comprehensively verified, so no inferences can yet be made about relative

abundance or shifts in elevational or geographic ranges or productivity of any species. The

wildlife camera system provides useful and standardized information, but only for a few species 

and covering only very limited areas. Although a preliminary herpetological inventory was 

conducted in the late 1960s (Ellis 1970), a comprehensive inventory of all of the monument’s 

current reptile and amphibian species has yet to be done. 

4.5.4.2 Extent and Connectivity of Important Terrestrial Habitats

What constitutes “habitat fragmentation” depends on the species and the structural characteristics

of the land uses that are purported to do the fragmenting. When assessing fragmentation,

conservation biologists often consider first the needs of species that have the largest home

ranges. Some biologists (e.g., Harrison 1992) have proposed that the width of a typical home

range of the focal species be considered the minimum for assessing the sufficiency of a habitat

corridor’s width. Biological thresholds for metrics relevant to fragmentation (e.g., minimum

patch size, corridor width, permeability of disturbed lands to species movements) are speciesspecific. 

Criteria

At a landscape scale, an important ecological goal is to sustain corridors or stepping-stones of

relatively unaltered habitat. For purposes of this assessment, “Good” conditions would be

represented by unbroken connectivity of natural vegetation on all sides of the monument. 

“Somewhat Concerning” would represent a measurable loss of corridors of habitat suitable for

locally rare or sensitive wildlife species, as a result of temporary setbacks of succession (e.g.,

fires, clearcuts), and/or declining populations of threatened species known to be area-sensitive. 

“Significant Concern” conditions would represent widespread and irreversible losses of those

corridors as a result of roads, buildings, and other newly unvegetated surfaces.

Condition and Trends

Somewhat Concerning – Medium Confidence. 

Nearly all of the fragmentation of habitat that has occurred in the vicinity of the monument 

happened over a century ago, with the building of roads and clearing of shrubland and forests for 

the expansion of agriculture in the Klamath Basin (Tables 11 and 12). Currently, little or no 

additional loss of habitat connectivity is occurring within or near the monument. No new 

highways have been constructed in many years. With a locally declining human population, there 

has been very little new residential development. New unpaved roads for ranching, logging, or 

energy development are few and mostly distant from the monument boundary. 
87

We did not rate the condition “Good” because some connectivity to undeveloped land cover has 

been compromised by agricultural land cover mainly to the north, and any further net loss of 

stands of sagebrush or large-diameter trees might, depending on location and configuration, 

interrupt movement corridors important to some area-sensitive species. We did not rate the 

condition “Significant Concern” because despite the historical loss of habitat connectivity due to 

agriculture, at least 70% of the monument’s perimeter is currently surrounded by large tracts of 

undeveloped land, and agricultural cover may be more permeable to movements of some species 

as compared to densely urbanized land. The monument’s generally good connectivity is

recognized by maps prepared by California Department of Fish and Wildlife, which show the

southern part of the monument as part of an “essential connectivity area” connecting to other 

natural lands in the region to the south and southeast. Coordinated actions of other agencies and 

private landowners could potentially re-establish some of the original habitat connectivity by 

restoring appropriate land cover at critical junctures. 

Table 11. Summary of reasonably foreseeable vegetation-altering actions on public land in and adjacent 

to the Modoc National Forest. (From the Modoc National Forest Travel Management Final Environmental

Impact Statement)
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Table 12. Road density by geographic unit within Lava Beds National Monument.

Geographic Unit (see Figure 4) Road Sum (km) Unit Area (sq km) Road Density (km/sq km)

Basalt and Andesite 37.91 84.52 0.4485

Basalt 2.00 12.42 0.1606

Basaltic Andesite 6.09 36.84 0.1654

Buttes 1.34 3.81 0.3501

Gillem’s Bluff 2.91 3.92 0.7428

Historic Lake Bed 5.87 2.86 2.0528

Lava Flows 0.74 7.25 0.1024

Petroglyphs Unit 1.13 0.70 1.6104

Total 57.98 152.33 0.3806

Assessment Confidence and Data Gaps

Medium Certainty. Connectivity is relatively simple to estimate at a coarse scale, so confidence 

is considered to be Medium rather than Low. Confidence in the condition and trend estimates 

was not considered to be High because land cover change maps for the period 1992-2001 that

were generated by the NPScape project are unlikely to portray most of the fine-scale 

fragmentation of forested areas that may have occurred near the monument. That is because they

mainly address conversions to agriculture or urban cover, which were extremely limited during

that time. Moreover, thresholds at which habitat patches within the monument might become less

used as a result of temporary fragmentation by wildfire are unknown for most of the monument’s

species, as are thresholds at which energy development or other land use conversions might harm

wildlife populations by disrupting movements.

4.6 Changes in Air Quality 

4.6.1 Background

Air quality is of interest aesthetically, ecologically, and for health reasons. Ozone, particulates, 

wet and dry deposition of nutrients, acidifying substances, pesticides, and other contaminants are 

monitored in many areas of North America, mainly due to concerns regarding their potentially 

harmful effects on biological communities and/or human health. Lava Beds began monitoring 

visibility in 1983 and is currently monitoring visibility and fine particles as part of the 

IMPROVE network.

4.6.2 Regional Context

Lava Beds is designated a Class I airshed, which is given the highest level of protection under 

the Clean Air Act. Air quality in this region is generally good relative to air quality in more 

urbanized areas or topographically confined basins. Nonetheless, the air quality in the monument 

is presumably degraded by widespread use of agricultural pesticides in surrounding areas, 
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several point sources in the Klamath Falls area, wood burning stoves, seasonal prescribed and

natural fires, and other sources. Because surface waters are lacking, concerns about air quality 

focus mainly on visibility and ozone, as well as the effects of deposition of atmospheric nitrate, 

sulfate, and contaminants on the park’s terrestrial ecosystems.

4.6.3 Issue Description

Fires within the monument or region have temporarily impaired air quality. But of perhaps 

greater concern because of their chronic nature is the deposition of airborne—and mainly 

particulate—nitrate (N), sulfate (S), and hydrocarbons that are carried to the monument from 

nearby agricultural fields and more distant developed areas. Increases in N, S, and other 

contaminants could alter soil biogeochemical processes and vegetation throughout the

monument. Lichens and mosses are particularly sensitive to N deposition because they largely

obtain their nitrogen directly from atmospheric sources (Geiser & Neitlich 2007, Jovan &

McCune 2006, Geiser et al. 2010).

Ozone levels are also a potential concern. In the lower atmosphere, ozone is an air pollutant,

forming when nitrogen oxides from vehicles, power plants, and other sources combine with

volatile organic compounds from gasoline, solvents, and vegetation in the presence of sunlight.

In addition to causing respiratory problems in people, ozone can injure plants. Ozone enters

leaves through pores (stomata), where it can kill plant tissues, causing visible injury, or reduce

photosynthesis, growth, and reproduction.

4.6.4 Indicators and Criteria to Evaluate Condition and Trends

Indicators that might be used to represent air quality concerns are:

• Atmospheric deposition of particulate nitrogen and sulfur

• Atmospheric deposition of pesticides and other contaminants 

• Ozone

4.6.4.1 Atmospheric Nitrogen (N) and Sulfur (S) Deposition

Criteria

The NPS Air Resources Division (NPS-ARD) has suggested that, for parks with N-sensitive 

resources, wet nitrate deposition greater than 1 kg per hectare per year indicates a “Significant

Concern.” Background levels for N wet deposition in the western U.S. are about 0.13 kg/ha/yr 

and 0.5 kg/ha/yr for total N deposition. Thus, “Good” condition would be represented by N and 

S deposition rates being close to the lowest ones detected in the region. “Somewhat Concerning” 

would be below the NPS-ARD criteria levels but without evidence of biological effects. 

“Significant Concern” would be when levels are above the NPS-ARD criteria levels and/or 

ecological changes can be traced to excessive N or S deposition. 

To protect all components of the forest ecosystem in the western Sierra Nevada, Fenn et al.

(2008) recommended a critical load threshold of 3.1 kg N per hectare per year. In the Pacific 

Northwest, many of the most sensitive lichen species are absent from areas where mean annual 

wet deposition exceeds 1-4 kg N per hectare per year and mean annual dry deposition exceeds 2-

6 kg N per hectare per year (Geiser et al. 2010). 
90

Condition and Trends 

Condition: Good. Confidence: Medium. 

Trends: Indeterminate. 

This monument’s risks of experiencing either acidification effects or enrichment effects from

atmospheric sulfur and nitrogen deposition were considered “very low”—the lowest of all 

Klamath Network parks (Sullivan et al. 2011a, b). Estimates of nitrogen deposition for the

monument during the period 2004-2009 obtained via interpolation from regional measurements

(NPS-ARD 2011) indicate no current need for concern (wet deposition rate was 0.5 kg/ha/yr

total N, precipitation-weighted, comprised of 0.4 NH4 and 1.0 NO3). For comparison, 

background levels in the western U.S. are about 0.50 kg/ha/yr for total N deposition. Similarly, 

estimates of sulfur wet deposition for the monument during the period 2004-2009 obtained via

interpolation from regional measurements indicate no current need for concern (0.2 kg/ha/yr total 

S, precipitation-weighted, comprised of 1.0 SO4).

Trends in N or S deposition cannot be determined because comparison of spatially interpolated

values between periods is not valid, and lichen N and S content has not been determined.

Assessment Confidence and Data Gaps

Medium Certainty. The interpolated estimates from NPS-ARD were calculated only for the

center of the monument. 

4.6.4.3 Airborne Contaminant Deposition

Toxics, including heavy metals like mercury, accumulate in the tissue of organisms. When

mercury converts to methylmercury in the environment and enters the food chain, effects can

include reduced reproductive success, impaired growth and development, and decreased

survival. Other toxic air contaminants of concern include pesticides, industrial by-products, and

flame retardants for fabrics. Some of these are known or suspected to cause cancer or other

serious health effects in humans and wildlife. 

Criteria

Thresholds for harm from many airborne contaminants are unknown. “Good” condition would 

be represented by all human-associated contaminants being below detectable levels. “Somewhat 

Concerning” would be levels that are detectable but below established guidelines for harm, and 

without evidence of ecological effects. “Significant Concern” would be levels that are both 

detected and found to exceed established guidelines and/or result in ecological damage. 

Condition and Trends

Condition: Indeterminate. 

Trends: Indeterminate.

Assessment Confidence and Data Gaps (all airborne pollutants)

Low Certainty. Too few measurements have been made to determine trends or even the existing 

levels of airborne contamination within the monument. Effects of airborne contaminants—

especially those that tend to accumulate and persist in food webs—need to be determined with 

regard to the monument’s most sensitive species and ecosystem processes. The monument’s 

lichens could be analyzed for pesticides and other hydrocarbons common in the surrounding 
91

agricultural lands, and levels compared with those already measured in western parks distant 

from agricultural sources. Efforts could be made to trace the infiltration pathways of herbicides 

and their associated ingredients in porous soils overlaying the monument’s caves. The initial 

analyses of contaminant loads in the monument’s bats could be continued and expanded.

4.6.4.4 Ozone

Criteria

The NPS-ARD (2010) guidance contains ozone criteria based on three metrics:

• 3-year average of the fourth highest daily maximum 8-hour average concentration, which 

should not exceed 75 ppb.

• SUM06: the running 90-day maximum sum of the 0800-2000 hourly ozone 

concentrations of ozone equal to or greater than 0.06 ppm, expressed in cumulative ppmhr. This should not exceed 8 ppm-hours.

• W126: cumulative index of exposure that uses a sigmoidal weighting function to give 

added significance to higher concentrations of ozone while retaining and giving less 

weight to mid and lower concentrations. The number of hours over 100 ppb (N100) is 

also considered in assessing the possible impact of the exposure. This should not exceed 

7 ppm-hours.

The first metric pertains to protection of human health, and the other two are for evaluating risk

to vegetation. In addition, summarizing the literature, Geiser & Neitlich (2007) note that ozone

levels of 20 to 60 μg per m3 may harm some lichens (Egger et al. 1994, Eversman and Sigal

1987). 

Condition and Trends

Condition: Somewhat Concerning – Low Certainty. 

Trends: Indeterminate. 

For the metrics described above and the period 2005-2009, the following were measured:

• fourth highest daily maximum 8-hour average concentration = 70.1 ppb

• SUM06 = 15.3 ppm-hrs

• W126 = 12.0 ppm-hrs

Levels of all three are close to the NPS thresholds for “Significant Concern” so the ozone threat 

in this monument could best be characterized as “Somewhat Concerning” both for humans and 

for vegetation. An NPS risk assessment also projected that the monument’s vegetation is at

“moderate” risk from ozone compared with other Klamath Network parks (NPS 2004). Of the 

monument’s many vascular plants, those most sensitive to ozone were predicted to be Jeffrey 

pine, ponderosa pine, quaking aspen, and Scouler's willow. None of these is widely distributed in 
92

the monument. Data are insufficient to validly determine trends in ozone concentrations or 

damage.

Assessment Confidence and Data Gaps

Low Certainty. Ozone levels need to be measured directly in the monument, consistently and 

over many years—not just interpolated from measurements elsewhere in the region. Most

importantly, ozone effects on the monument’s plants (especially the community composition of

lichens and mosses near cave entrances) need to be determined and thresholds established. 

4.7 Changes in the Natural Quality of the Park Experience

4.7.1 Background

Several attributes influence the natural quality of the park experience that is valued by most

visitors. Among these attributes are long-distance visibility, a starlit night sky, quiet

surroundings, and the absence of signs of human alteration. These are discussed in this section.

4.7.2 Regional Context

The monument is within a day’s drive of Portland, San Francisco, and some other major cities. 

Each year, the monument provides thousands of visitors with opportunities for recreation and a

connection with nature.

4.7.3 Issue Description

With increasing population growth projected for the Pacific Northwest generally, an opportunity 

exists both for broader enjoyment of the monument’s resources and for increasing impairment of 

solitude, quiet settings, untrammeled landscapes, good visibility, and a dark night sky.

4.7.4 Indicators and Criteria to Evaluate Condition and Trends

Indicators that might be used to monitor this issue (Natural Quality of the Park Experience)

include the following:

1. Visibility

2. Night Sky

3. Soundscape

4. Physical Remoteness and Solitude

5. Disturbed Area Recovery

4.7.4.1 Visibility

The 1977 amendments to the Clean Air Act declared the monument a mandatory Class I area and 

charged the Federal Land Manager with a responsibility to protect air quality related values, 

including visibility. Visibility is the clarity of the atmosphere, as typically measured by the

viewable distance at a particular location and time, and the number of days annually that scenic

objects at different distances can be seen. Visibility is restricted by the absorption and scattering

of light that are caused by both gases and particles in the atmosphere. Natural factors that

decrease visibility include relative humidity above 70 percent, fog, precipitation, blowing dust

and snow, and smoke from wildland fires. Human activities reduce visibility when soil is

disturbed and creates dust, as well as when fossil fuels are burned which results in soot and tiny

visibility-reducing particles (aerosols). In rural areas, such as those in the vicinity of the 

monument, the greatest contributors to reduced visibility are carbon and, especially, sulfate. An
93

NPS study in the Pacific Northwest during the summer of 1990 found that sulfates accounted for

over 40 percent of the visibility reduction, whereas carbon (organics and light absorbing carbon)

was responsible for about 20 percent and nitrates and coarse mass for 10 percent. Measurements

in the spring of 2002 noted that the majority of dust in northern California came from long-range

transport across the Pacific (Cameron-Smith et al. 2005).

Criteria

The visibility criteria used by the NPS are based on the deviation of the current Group 50 

visibility conditions from estimated Group 50 natural visibility conditions, where Group 50 is 

defined as the mean of the visibility observations falling within the range from the 40th through 

the 60th percentiles. Visibility is estimated from the interpolation of the five-year averages of the 

Group 50 visibility. Visibility in this calculation is expressed in terms of a Haze Index in 

deciviews (dv). As the Haze Index increases, the visibility worsens. The visibility condition is 

expressed as current Group 50 visibility minimums, the estimated Group 50 visibility under 

natural conditions. 

“Good” condition is assigned to parks with a visibility condition estimate of less than 2 dv above

estimated natural conditions. Parks with visibility condition estimates of 2-8 dv above natural

conditions are considered to be in “Moderate” condition (we instead use the term, “Somewhat

Concerning”) and parks with visibility condition estimates greater than 8 dv above natural

conditions are considered to be of “Significant Concern.” The NPS chose the dv ranges of these

categories to reflect as nearly as possible the variation in visibility conditions across the nation’s

visibility monitoring network.

Condition and Trends

Condition: Somewhat Concerning – High Certainty.

Trends: Indeterminate. 

The most recent NPS assessment (NPS-ARD 2011), measured during 2006-2010, suggests the

condition of the monument’s visibility should be categorized as “moderate” because the average 

annual Group 50 visibility after adjustment for natural conditions was measured as 3.5 

deciviews. Within the monument, visibility may be impaired by dust blowing from unpaved 

roads, smoke from campgrounds, occasional prescribed burns, and wildfires. From outside the 

monument, vehicle and wood stove emissions, agricultural dust, fall burning of agricultural 

lands, debris burning, and wood-fired industrial boilers contribute to hazy conditions. 

Trends

The most recent NPS assessment (NPS-ARD 2011) reported a slight (but not statistically 

significant) improvement in visibility on the clearest days, and no statistically significant trend in 

the monument’s visibility conditions on the haziest days during the period 1999 to 2008. Over a 

longer period there also does not appear to be an obvious trend (Figure 23).
94

Figure 23. Visibility (in deciview units) from the monument, 1990 to 2010. (From IMPROVE web site:

http://views.cira.colostate.edu/web)

Assessment Confidence and Data Gaps

High Certainty. The monument monitors particulates year-round as part of the IMPROVE12

national monitoring network. Those data describe the visibility conditions reasonably well. 

4.7.4.2 Night Sky

Natural lightscapes are critical for nighttime scenery, such as viewing a starry sky in its finest

detail. They are also critical for maintaining nocturnal habitat of many wildlife species which

rely on natural patterns of light and dark for navigation, to cue behaviors, or hide from predators.

Human-caused light may be obtrusive in the same manner that noise can disrupt a contemplative

or peaceful scene. Light that is undesirable in a natural or cultural landscape is often called "light

pollution."

Criteria 

The NPS has not recommended specific criteria for sky brightness, but has developed a system

for measuring sky brightness to quantify the source and severity of light pollution. This system

uses a research-grade digital camera to capture the entire sky with a series of images. A less 

precise representation of dark sky can be gained with the unaided eye using the Bortle scale, a 

qualitative assessment which ranges from 1 (darkest night sky) to 9 (brightest). 

Condition and Trends

Condition: Good – Moderate Certainty. 

Trend: Indeterminate. 

 

12 Interagency Monitoring of Protected Visual Environments 
95

The monument has been nominated as a Dark Night Sky park, and the night sky is currently

rated a 2 on the 9-level Bortle scale (National Park Service 2012). Trends have not been 

determined. All lighting fixtures in the monument have been inventoried and all lamps have been 

retrofitted to meet dark sky standards. However, surrounding communities have enacted no

lighting ordinances to preserve the night sky. Minor light pollution is apparent low along the

Northern horizon, with a low light dome visible over Klamath Falls. There is also some light

interference from developments along the State Highway 139 corridor. Agricultural operations 

by Petroglyph Point have extensive outdoor lighting that affects dark night skies at this location. 

Assessment Confidence and Data Gaps

Confidence in the condition was not rated higher because of the qualitative nature of the Bortle 

assessment. More replicable measures of Night Sky conditions and trends could involve using a 

sky quality meter and/or digital-camera based protocol. Imagery from the Defense Military 

Satellite Program (DMSP) might also be helpful.

4.7.4.3 Soundscape

Since 2006, the National Park Service has required parks to identify the levels and types of

unnatural sound that constitute acceptable and unacceptable impacts on park natural

soundscapes. This is not only for the benefit of visitors, but is also to protect species that require

often-subtle auditory cues for reproduction, predator avoidance, navigation, and communication 

about food locations. 

Criteria

The NPS has not recommended specific criteria for soundscape integrity. “Good” condition 

might be represented by presence of natural sounds only and human-related sounds that travel 

only short distances for short periods of time. “Somewhat Concerning” and “Significant 

Concern” might be unnatural sounds that travel greater distances and/or are constant or 

noticeable for longer periods of time. 

One way of quantifying human-sourced interference with natural sounds is to measure the 

amount of time that sound pressure levels (SPL’s)—measured in decibels (dB) and weighted 

(dBA) to resemble the response of the human ear—exceed a given value. This can be determined 

with electronic acoustical monitoring systems. A common reference value range is 35-55 dBA 

because some studies have noted speech interference and impacts to wildlife above that range, 

depending also on the soundwave frequency. 

Condition and Trends

Condition: Good – Medium Certainty.

Trends: Indeterminate.

The following components of the monument’s soundscape are ones commonly recognized:

• Wildlife: During the morning and throughout the day, the vocalizations of songbirds are a

dominant feature, along with the chattering of squirrels. In the evening and at night, calls 

of insects and owls are common.

• Wind: Wind blowing through the trees or across the rangeland. Trees creaking/rubbing

against each other.
96

• The varied sounds of rainfall on vegetation and the ground.

• Occasionally some memorable thunderstorms. 

The park soundscape is impacted by vehicle traffic, military and civilian over flights, generators 

from the monument campground, various operations and facilities, and snowmobiles from the 

Doorknob Snowmobile Park just outside the monument. Drilling associated with proposed 

geothermal development just outside the southern boundary of the monument could increase 

noise, vibration, and general disturbance.

Loud sounds that sometimes adversely affect the monument’s soundscape:

• Vehicle traffic on monument roads. This intrusion can be heard from many places in the

monument. Traffic is generated from many sources (visitors, staff, contractors) using

many vehicle types; the most intrusive noises tend to be generated from motorcycles,

although noise from passenger cars and RVs is persistent during the day, and sounds of 

snowmobiles and other off-road vehicles just outside the monument can sometimes be 

heard.

• Campground and day use area noise. Generators, music, doors slamming, etc. This tends

to be concentrated and because the campgrounds are in well-vegetated areas, the sounds

do not travel far.

• Staff housing area noise. Dogs barking from the penned area in the housing loop can be 

heard for well over a mile away.

• Construction and maintenance noise. Work on and around buildings and other facilities

can be very noisy.

• Forestry work. This intrusion is created by chainsaws, chippers, and other powered

equipment. These sounds are significant but infrequent and irregular in occurrence.

• Aircraft. This intrusion is mostly from high elevation commercial flights but is heard

regularly everywhere in monument.

Assessment Confidence and Data Gaps

Medium Certainty for current condition, Indeterminate Certainty for trends and for the capacity 

to interpret the data in terms of likely impacts on people and wildlife. 

4.7.4.4 Physical Remoteness and Solitude

The monument has two Wilderness units (Schonchin and Black Lava Flow) totaling 28,460 acres 

and covering almost two-thirds of the monument’s area. Wilderness and backcountry are 

managed identically, to the extent possible, as stated in the 2006 Wilderness Stewardship Plan, 

and total approximately 45,636 acres. There are 38 miles of maintained trails and 12 miles of 

unmaintained trails in the backcountry and wilderness areas of the monument. 

Criteria

Wilderness qualities, each of which has been defined administratively, are:

• Untrammeled
97

• Natural

• Undeveloped

• Solitude or primitive and unconfined recreation quality

No numeric criteria exist for assessing these. 

Condition and Trends

Condition: Good – Medium Certainty. 

Trends: Indeterminate.

Qualitatively, nearly the entire monument appears to have the qualities listed above. A few 

developments are visible from the Schonchin Wilderness, including the monument’s housing and 

visitor center buildings, but otherwise visual intrusions are not obvious. Most monument visitors

are able to find many opportunities for physical remoteness and solitude. A great majority of 

visitors coming to the monument come between June and September. By far the most visitors

spend the bulk of their time at the lava tube caves that are open to the public. Off-road vehicles 

occasionally trespass from the surrounding National Forest. 

Data are insufficient to detect any trend in Physical Remoteness and Solitude. The number of 

tourist visits, and thus automobile traffic, appears to have increased gradually. Data on visits to 

11 visitor use caves during the period 1992-2008 (Figure 24) do not show an obvious trend.

Figure 24. Total visits in 11 monitored visitor use caves during 1992-2008. 

Assessment Confidence and Data Gaps

Medium Certainty. Although total visits to the monument are tallied annually, visits to various

areas within the monument are not routinely tallied, nor are the disturbances potentially

associated with those. Visits to half of the public use caves are not monitored, and visitation data 

on the other public use caves may be of limited accuracy, duration, and consistency. 
98

Implementation of the Klamath Network’s new cave entrance monitoring protocol (Krejca et al.

2010) will result in more consistent collection of such data.

4.7.4.5 Disturbed Area Recovery

While some infrastructure is obviously necessary to support the immediate safety and comfort of

visitors, some artificial features—mostly ones that are hold-overs from when land uses were

unrestricted before the monument was established—can be a problem. Some create a visual

blight, fragment wildlife habitat, disrupt natural water flows, and provide an opportunity for the

establishment of non-native plants. Actively restoring or otherwise speeding the recovery of

these areas is a priority for monument staff.

Criteria

For purposes of this assessment, “Good” conditions would be represented by a park landscape

with no disturbed lands except those currently vital to visitor support. It would also involve

complete restoration or recovery of all artificially disturbed lands within the park that are not

currently vital to visitor support. “Somewhat Concerning” and “Significant Concern” would 

reflect increasing extent of unrestored lands. 

Condition and Trends

Condition: Good – High Certainty. 

Trends: Improving. 

For the monument as a whole, natural succession and planned restoration appears to be gradually

leading to visual recovery in most areas historically disturbed by logging, grazing, or other 

disturbances. Since designation of the monument, limited development has occurred to provide 

for transportation, monument administration, and visitor services and access. Inevitably, 

development has disturbed or displaced natural vegetation and soils. Borrow pits historically 

excavated for road construction have mostly been stabilized. Some old roads have been 

abandoned and are now used as trails. 

Assessment Confidence and Data Gaps

Moderate Certainty. Most of the monument’s major land disturbances were systematically 

inventoried by Ziegenbein et al. (2006).
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5.0 Discussion

Table 13 summarizes what this document has reported about the condition and trends of each of 

the seven major resource concerns identified at Lava Beds National Monument. Partly because 

lava caves are the feature most responsible for drawing visitors to Lava Beds National 

Monument, the greatest concerns have focused on the physical and biological condition of those 

caves. Physically, the risks of greatest concern are those that threaten the microclimate of the 

caves, particularly the caves that contain perennial ice. The cave microclimate could be placed at 

greater risk by increased visitation, decreasing aboveground precipitation, warming aboveground 

temperatures, and as perhaps by falling regional water tables. These factors are even more likely 

to alter the monument’s aboveground vegetation and wildlife. Biologically, the feature of the 

lava caves receiving the most recognition to date has been their bats. Bat populations are likely 

to be exposed to pesticides used widely in the agricultural lands surrounding the monument. 

Effects of pesticides and other contaminants on bat populations within the monument have yet to 

be determined. Fortunately, there is no evidence that White Nose Syndrome—a recent cause of 

mass mortalilty among bats in eastern North America—has arrived at the monument. 

Cave organisms could also be affected to an unknown degree by herbicide applications in lands 

that overlie the caves, as well as by changes in cave water budgets resulting from changes in 

aboveground vegetation cover. Vegetation shifts that have occurred have diminished—and will 

continue to diminish—populations of many of the monument’s wildlife species that depend on 

habitats characterized by sagebrush, bunchgrass, or large conifers. Cheatgrass which spreads and 

remains indefinitely in disturbed areas slows the regeneration of shrubs and pines, and it occurs 

at the expense of more diverse native plant communities. Fires occur fairly often in this dry 

country, and both their extent and negative effects have been exacerbated by widespread postfire establishment of cheatgrass. Even fires as infrequent as one every 30 to 50 years could 

maintain vegetation dominated by cheatgrass at the monument. 

Understanding of condition and trends of the monument’s natural resources, as essential to their 

sound management, could perhaps benefit the most from new or expanded research on 

relationships between precipitation, infiltration, groundwater levels, and cave microclimates; as 

well as between visitor use and cave microclimates. Also important is monitoring of: ice and 

microclimate in additional caves; effects of pesticides and other contaminants on cave fauna; 

energetics studies of bats as related to local availability of the insects upon which they forage; 

taxonomically intensive surveys of invertebrates in more caves; factors that may allow the 

bunchgrass community to persist in relationship to cheatgrass and fire; and surveys of the 

monument’s reptiles and small mammals, especially as they may be impacted by cheatgrass 

invasion.
100

Table 13. Summary of ratings for indicators of condition and trend used in this analysis of Lava Beds National Monument. See chapter narratives

for criteria and justification of each rating.

Priority Issue Indicators

Potential 

Value as 

Indicator

Condition 

Rating Certainty Trend Rating Certainty

Spatial 

Coverage

Temporal 

Coverage

Changes in

Climate

Aboveground

Temperature &

Precipitation

Good Indeterminate Somewhat 

Concerning

Medium Fair Good

Cave Microclimate Good Indeterminate Indeterminate Poor Poor

Ice Formation & 

Persistence

Fair Indeterminate Somewhat 

Concerning 

(Significant 

Concern for 3 

caves)

High Fair Poor

Changes in Cave Geologic Features Fair Somewhat 

Concerning

Low Indeterminate Poor Poor

Changes in Cave-dependent Species Good Mixed Mixed Indeterminate Fair Poor

Changes in

Vegetation

Cheatgrass Good Significant

Concern

High Significant

Concern

High Good Fair

Other Invasives Good Significant 

Concern

Medium Indeterminate Fair Poor

Juniper Fair Somewhat 

Concerning

Medium Somewhat 

Concerning

Medium Good Fair

Sagebrush Good Significant

Concern

Medium Significant

Concern

Medium Good Poor

Bunchgrasses Fair Somewhat 

Concerning

Medium Somewhat 

Concerning

Medium Medium Poor
101

Table 13. Summary of ratings for indicators of condition and trend used in this analysis of Lava Beds National Monument. See chapter narratives

for criteria and justification of each rating.

Priority Issue Indicators

Potential 

Value as 

Indicator

Condition 

Rating Certainty Trend Rating Certainty

Spatial 

Coverage

Temporal 

Coverage

Rare Species;

Diversity of Native

Plant Species

Poor Indeterminate Indeterminate Poor Poor

Changes in

Aboveground

Wildlife

Diversity of Native

Terrestrial Wildlife

Species & Rare

Species

Fair Somewhat

Concerning

Low Indeterminate Fair Poor

Connectivity & Extent

of Important

Terrestrial Habitats

Good Somewhat

Concerning

Medium Somewhat 

Concerning

Medium Fair Poor

Changes in

Air Quality

Deposition of

Atmospheric Nitrogen

and Sulfur

Fair Good Medium Indeterminate N/A Poor

Deposition of Airborne

Contaminants

Fair Indeterminate Indeterminate Indeterminate Poor

Ozone Fair Somewhat

Concerning

Low Indeterminate Low N/A Poor
102

Table 13. Summary of ratings for indicators of condition and trend used in this analysis of Lava Beds National Monument. See chapter narratives

for criteria and justification of each rating.

Priority Issue Indicators

Potential 

Value as 

Indicator

Condition 

Rating Certainty Trend Rating Certainty

Spatial 

Coverage

Temporal 

Coverage

Changes in

the Natural

Quality of the

Park

Experience

Visibility Fair Somewhat

Concerning

High Indeterminate Indeterminate N/A Poor

Night Sky Good Good Medium Indeterminate Indeterminate N/A Poor

Soundscape Good Good Medium Indeterminate Mixed Poor Poor

Physical Remoteness

and Solitude

Good Good Medium Indeterminate Indeterminate Good Poor

Disturbed Area

Recovery

Fair Good High Improving Medium Good Fair
103

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A-1

Appendix A. Climate of Lava Beds National Monument: 

supporting data and maps
A-2

Figure A1. Annual precipitation for Lava Beds National Monument (LABE) from the PRISM 1971-2000 

Climate Normals (Daly et al. 2008). This map was prepared by investigators for the LANDFIRE project 

who extrapolated information using Landsat Thematic Mapper and other data. The inset table gives the 

spatially derived quartiles of all grids that fall within the park boundary.
A-3

Figure A2. Average annual temperatures for Lava Beds National Monument (LABE) from the PRISM 

1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the 

LANDFIRE project who extrapolated information using Landsat Thematic Mapper and other data. The 

inset table gives the spatially derived quartiles of all grids that fall within the park boundary.
A-4

Figure A3. Average annual maximum temperatures for Lava Beds National Monument (LABE) from the 

PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the 

LANDFIRE project who extrapolated information using Landsat Thematic Mapper and other data. The 

inset table gives the spatially derived quartiles of all grids that fall within the park boundary.
A-5

Figure A4. Average annual minimum temperatures for Lava Beds National Monument (LABE) from the 

PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the 

LANDFIRE project who extrapolated information using Landsat Thematic Mapper and other data. The 

inset table gives the spatially derived quartiles of all grids that fall within the park boundary.
A-6

Figure A5. Average precipitation for the winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons for Lava Beds National Monument 

(LABE) from the PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the LANDFIRE project who 

extrapolated information using Landsat Thematic Mapper and other data. The inset table gives the spatially derived quartiles of all grids that fall 

within the park boundary.
A-7

Figure A6. Average temperatures for the winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons for Lava Beds National Monument 

(LABE) from the PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the LANDFIRE project who 

extrapolated information using Landsat Thematic Mapper and other data. The inset table gives the spatially derived quartiles of all grids that fall 

within the park boundary.
A-8

Figure A7. Average maximum temperatures for the winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons for Lava Beds National 

Monument (LABE) from the PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the LANDFIRE 

project who extrapolated information using Landsat Thematic Mapper and other data. The inset table gives the spatially derived quartiles of all 

grids that fall within the park boundary.
A-9

Figure A8. Average minimum temperatures for the winter (DJF), spring (MAM), summer (JJA), and fall (SON) seasons for Lava Beds National 

Monument (LABE) from the PRISM 1971-2000 Climate Normals (Daly et al. 2008). This map was prepared by investigators for the LANDFIRE 

project who extrapolated information using Landsat Thematic Mapper and other data. The inset table gives the spatially derived quartiles of all 

grids that fall within the park boundary.
A-10

Figure A9. Climate stations in the vicinity of Lava Beds National Monument (LABE) (Daly et al. 2009). 

Stations highlighted in the map are further referenced in the report.
A-11

Figure A10. 1971–2000 average monthly mean temperature for the stations at Lava Beds NM, Tulelake, 

and the Lava Beds (LABE) park average of the PRISM modeled data (Daly et al. 2009). Date refers to the 

month of the year.

Figure A11. 1971–2000 average monthly maximum temperature for the stations at Lava Beds NM, 

Tulelake, and the Lava Beds (LABE) park average of the PRISM modeled data (Daly et al. 2009). Date 

refers to the month of the year.
A-12

Figure A12. 1971–2000 average monthly minimum temperature for the stations at Lava Beds NM, 

Tulelake, and the Lava Beds (LABE) park average of the PRISM modeled data (Daly et al. 2009). Date 

refers to the month of the year. 

Figure A13. 1971–2000 average monthly daily temperature range for the stations at Lava Beds NM, 

Tulelake, and the Lava Beds (LABE) average of the PRISM modeled data (Daly et al. 2009). Date refers 

to the month of the year.
A-13

Figure A14. 1971–2000 average monthly precipitation for the stations at Lava Beds NM, Tulelake, and 

the Lava Beds (LABE) average of the PRISM modeled data (Daly et al. 2009). Date refers to the month of 

the year.

Figure A15. Time series of mean annual temperature for LABE from the park average of the PRISM

modeled data (Daly et al. 2009). Black line is a five year moving average and the blue line is the trend 

associated with the regression parameters (inset). Date refers to year.
A-14

Figure A16. Time series of mean annual maximum temperature for LABE from the park average of the 

PRISM modeled data (Daly et al. 2009). Black line is a five year moving average and the blue line is the 

trend associated with the regression parameters (inset). Date refers to year.

Figure A17. Time series of mean annual minimum temperature for LABE from the park average of the 

PRISM modeled data (Daly et al. 2009). Black line is a five year moving average and the blue line is the 

trend associated with the regression parameters (inset). Date refers to year.
A-15

Figure A18. Time series of mean annual daily temperature range for LABE from the park average of the 

PRISM modeled data (Daly et al. 2009). Black line is a five year moving average and the blue line is the 

trend associated with the regression parameters (inset). Date refers to year.

Figure A19. Time series of annual precipitation for CRLA from the park average of the PRISM modeled 

data (Daly et al. 2009). Black line is a five year moving average and the blue line is the trend associated 

with the regression parameters (inset). Date refers to year.
A-16

Table A1. Regression parameters and statistics for core climate elements for different time periods for Lava Beds National Monument using 

PRISM modeled data (Daly et al. 2009). Slope p-values significant at the 90% confidence level (α=0.10) are shown in bold.

Annual Precipitation

Annual Maximum 

Temperature

Annual Minimum 

Temperature Annual Mean Temperature

Time Period 

(years)

Slope 

(mm/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

1895–2007 2.223 0.347 0.017 0.429 0.035 0.081 0.026 0.141

1971–2007 -0.573 0.969 0.321 0.007 0.203 0.034 0.262 0.006
A-17

Table A2. Regression parameters and statistics for core climate elements for 1895–2007 for Lava Beds National Monument using PRISM 

modeled data (Daly et al. 2009). Slope p-values significant at the 90% confidence level (α=0.10) are shown in bold.

Precipitation Maximum Temperature Minimum Temperature Mean Temperature

Month

Slope 

(mm/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

January -0.639 0.391 0.104 0.087 0.103 0.184 0.103 0.118

February -0.516 0.484 0.093 0.144 0.058 0.388 0.075 0.214

March -0.062 0.933 0.071 0.319 0.079 0.078 0.075 0.158

April 0.586 0.170 -0.097 0.178 0.005 0.906 -0.046 0.369

May 0.512 0.361 0.013 0.850 0.047 0.212 0.030 0.545

June 0.367 0.518 -0.012 0.849 0.048 0.149 0.018 0.678

July 0.171 0.554 -0.000 0.997 0.029 0.427 0.015 0.724

August 0.443 0.205 0.002 0.962 0.014 0.685 0.008 0.828

September -0.150 0.651 0.124 0.037 0.034 0.367 0.079 0.071

October -0.211 0.767 0.034 0.606 -0.007 0.845 0.013 0.755

November 0.810 0.303 -0.109 0.083 -0.017 0.727 -0.063 0.147

December 0.913 0.265 -0.016 0.760 0.026 0.664 0.005 0.925

Annual 2.223 0.347 0.017 0.429 0.035 0.081 0.026 0.141
A-18

Table A3. Regression parameters and statistics for core climate elements for 1971–2007 for Lava Beds National Monument using PRISM 

modeled data. Slope p-values significant at the 90% confidence level (α=0.10) are shown in bold. (Daly et al. 2009)

Precipitation

Maximum 

Temperature Minimum Temperature Mean Temperature

Month

Slope 

(mm/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

January 2.330 0.553 0.444 0.111 0.643 0.074 0.543 0.075

February 0.898 0.828 0.082 0.808 -0.012 0.969 0.035 0.906

March -4.459 0.309 0.772 0.042 0.308 0.179 0.539 0.060

April 2.463 0.304 0.297 0.428 0.395 0.069 0.346 0.221

May 1.624 0.642 0.189 0.630 0.366 0.055 0.278 0.308

June -0.002 0.999 0.184 0.574 0.060 0.778 0.122 0.634

July -0.540 0.765 0.593 0.038 0.351 0.071 0.473 0.041

August -3.083 0.214 0.417 0.126 0.071 0.676 0.245 0.225

September -1.810 0.329 0.455 0.176 0.062 0.743 0.258 0.294

October -2.783 0.408 0.153 0.692 -0.033 0.866 0.060 0.814

November 2.130 0.617 0.213 0.547 -0.000 1.000 0.107 0.686

December 2.659 0.600 0.046 0.875 0.235 0.467 0.140 0.618

Annual -0.573 0.969 0.321 0.007 0.203 0.034 0.262 0.006
A-19

Table A4. Regression parameters and statistics for core climate elements for 1971–2007 at Lava Beds NM. Slope p-values significant at the 90% 

confidence level (α=0.10) are shown in bold. (Daly et al. 2009)

Precipitation Maximum Temperature Minimum Temperature Mean Temperature

Month

Slope 

(mm/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope 

(°C/10 yr) p-value

Slope (°C/10 

yr) p-value

January 3.215 0.576 0.631 0.029 0.508 0.143 0.563 0.065

February 3.720 0.473 0.190 0.586 -0.060 0.847 0.063 0.841

March -4.052 0.549 0.974 0.014 0.382 0.157 0.671 0.036

April 1.590 0.578 0.214 0.563 0.343 0.223 0.196 0.531

May -1.175 0.774 0.361 0.413 0.224 0.333 0.288 0.364

June -0.917 0.784 0.524 0.163 0.026 0.925 0.267 0.389

July 0.819 0.658 0.746 0.023 0.298 0.194 0.525 0.047

August -1.871 0.499 0.473 0.136 -0.003 0.991 0.212 0.429

September -1.107 0.550 0.537 0.114 0.018 0.945 0.274 0.334

October -5.760 0.151 0.729 0.078 0.042 0.867 0.385 0.211

November 5.856 0.238 0.276 0.480 -0.165 0.514 0.060 0.843

December 0.811 0.884 0.158 0.622 0.210 0.523 0.207 0.513

Annual -6.057 0.854 0.518 0.001 0.347 0.022 0.411 0.004
A-20

Table A5. Regression parameters and statistics for core climate elements for 1971–2007 at Tulelake. Slope p-values significant at the 90% 

confidence level (α=0.10) are shown in bold. (Daly et al. 2009)

Precipitation Maximum Temperature Minimum Temperature Mean Temperature

Month

Slope 

(mm/10 yr) p-value

Slope (°C/10 

yr) p-value

Slope 

(°C/10 yr) p-value

Slope (°C/10 

yr) p-value

January 4.341 0.171 0.186 0.623 0.562 0.274 0.386 0.367

February 1.412 0.648 -0.195 0.626 -0.246 0.490 -0.222 0.511

March -2.897 0.360 0.263 0.530 -0.009 0.972 0.134 0.629

April 2.841 0.298 0.015 0.967 0.520 0.007 0.271 0.288

May 5.401 0.135 -0.389 0.319 0.573 0.008 0.085 0.747

June -0.267 0.921 0.023 0.940 0.171 0.374 0.100 0.659

July -0.439 0.827 0.134 0.641 0.356 0.096 0.250 0.301

August -4.266 0.201 0.050 0.854 0.138 0.391 0.093 0.629

September -2.300 0.277 0.066 0.841 0.046 0.754 0.050 0.806

October -1.865 0.563 -0.245 0.539 0.115 0.550 -0.070 0.760

November 1.339 0.721 -0.206 0.585 0.099 0.754 -0.039 0.888

December 2.633 0.570 0.209 0.533 0.543 0.194 0.381 0.276

Annual 6.137 0.706 0.007 0.971 0.262 0.061 0.140 0.301
A-21

Table A6. Regression statistics for the 27 core climate extremes indices for the two representative climate stations for LABE. All trends statistically 

significant at the 0.05 level shown in bold.

Indices/Stations/Trend Statistics

Lava Beds (1960-2011) Tulelake (1932-2011)

R2 p-value Slope R2 p-value Slope

# of Days Tmax >25°C (days) 0.24 0.004 0.456 NS 0.507 0.050

# of Days Tmax <0°C (days) 0.24 0.004 -0.188 NS 0.878 0.005

# of Days Tmin >20°C (days) NS 0.969 0.000 Not Observed

# of Days Tmin <0°C (days) NS 0.767 -0.053 NS 0.161 -0.167

# of Days Tmin <-10°C (days) NS 0.093 -0.147 NS 0.064 -0.108

Growing Season Length (days) NS 0.444 0.268 NS 0.905 0.019

Maximum Tmax (°C) 0.16 0.021 0.048 NS 0.762 0.003

Minimum Tmax (°C) 0.25 0.003 0.155 NS 0.477 0.012

Maximum Tmin (°C) NS 0.256 0.024 NS 0.781 0.003

Minimum Tmin (°C) NS 0.075 0.095 NS 0.191 0.031

% of Days Tmax <10th Percentile (%) 0.37 0.000 -0.130 NS 0.546 -0.010

% of Days Tmax >90th Percentile (%) 0.19 0.011 0.103 NS 0.400 -0.020

% of Days Tmin <10th Percentile (%) NS 0.090 -0.072 0.11 0.008 -0.078

% of Days Tmin >90th Percentile (%) NS 0.958 -0.002 NS 0.250 0.032

Warm Spell Duration Index (days) 0.23 0.004 0.177 NS 0.871 -0.006

Cold Spell Duration Index (days) NS 0.935 0.004 0.11 0.009 -0.097

Diurnal Temperature Range (°C) 0.21 0.009 0.021 NS 0.078 -0.014
A-22

Indices/Stations/Trend Statistics

Lava Beds (1960-2011) Tulelake (1932-2011)

R2 p-value Slope R2 p-value Slope

Maximum 1-Day Precipitation (mm) NS 0.220 -0.204 NS 0.921 0.004

Maximum 5-Day Precipitation (mm) NS 0.363 -0.394 NS 0.861 0.016

Simple Precipitation Intensity Index (mm/day) NS 0.545 -0.008 NS 0.338 -0.004

Annual # of Days Precipitation >10 mm (days) NS 0.628 0.024 NS 0.857 0.003

Annual # of Days Precipitation >20 mm (days) NS 0.746 -0.007 NS 0.701 -0.002

Maximum Length of Dry Spell (days) NS 0.215 -0.247 NS 0.432 -0.088

Maximum Length of Wet Spell (days) NS 0.624 -0.007 0.07 0.037 0.019

Annual # of Days with Precipitation >95 Percentile 

(days) NS 0.488 -0.535 NS 0.555 -0.123

Annual # of Days with Precipitation >99 Percentile 

(days) NS 0.238 -0.564 NS 0.527 -0.090

Annual Precipitation Total (mm) NS 0.852 -0.227 NS 0.410 0.331
A-23

Figure A20. Example time series of the number of days when the maximum temperature is above the 

90th percentile during the reference period observed each year at Lava Beds National Monument, 

California, during 1960-2011. Trends are computed by linear least square (solid line) and locally weighted 

linear regression (dashed line). Missing data is handled as discussed in the text.

Figure A21. Example time series of the number of days when the minimum temperature is below the 10th

percentile during the reference period observed each year at Tulelake, California, during 1932-2011. 

Trends are computed by linear least square (solid line) and locally weighted linear regression (dashed 

line). Missing data is handled as discussed in the text.

B-1

Appendix B. Physical Characteristics of Lava Beds National 

Monument: supporting data and maps
B-2

Figure B1. Mapped elevation classes in Lava Beds National Monument (USGS 2011). Scale: 10 meters.
B-3

Figure B2. Mapped slope classes in Lava Beds National Monument (USGS 2011). Scale: 10 meters.
B-4

Figure B3. Mapped aspect classes in Lava Beds National Monument (USGS 2011). Scale: 10 

meters. This is a raster file that identifies the orientation or direction of slope. Aspect is the 

down-slope direction of a cell to its neighbors. The cell values in an aspect grid are compass 

directions ranging from 0° to 360°; north is 0° and, in a clockwise direction, 90° is east, 180° is 

south, and 270° is west. Input grid cells that have 0° slope (flat areas) are assigned an aspect 

value of -1. This file was created from the DEM using the Aspect tool located in the Spatial 

Analyst toolbox provided in the ArcGIS software.
B-5

Figure B4. Mapped lithologic classes in Lava Beds National Monument (USGS 2005). Scale: 1:500,000 

(Chris Wayne, NPS Klamath Network, pers. comm.)
B-6

Figure B5. Mapped soil complexes in Lava Beds National Monument. Scale: 1:24,000. The SSURGO 

soil data map was simplified by using the dissolve tool, located in the Data Management toolbox provided 

in ArcGIS software, to combine multiple shapefiles of the same soil type into one single shapefile. The 

single shapefile was then grouped with other dissolved soil shapefiles of the same soil complex root 

name. The final output was single shapefiles of soil complexes, each containing multiple individual soil 

types from the same soil complex. The goal of 'simplifying' the data was to make the map less congested 

and easier to read.
C-1

Appendix C. Vegetation and Fire Characteristics of Lava 

Beds National Monument: supporting data and maps
C-2

Table C1. Biophysical settings: percentages by geographic unit (LANDFIRE 2008). 

Table C1. % of Geographic Unit

General Biophysical Setting

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Aspen and Woodland 0.00 0.22 0

Barren 1.60 30.46 5.93 16.98 0.47 0.20 77.58 1.22 8730.58 19

Chaparral 0.00 0.21 0.01 0.00 0.00 10.64 0

Conifer Wooded Steppe 0.10 4.41 0

Desert Scrub 0.02 0.02 0.03 4.78 0

Greasewood Flat 0.65 0.01 22.73 58.89 434.42 1

Juniper Woodland and 

Savanna

26.66 9.81 29.37 30.13 49.80 14.79 5.42 19.60 10426.44 22

Lodgepole 0.89 0.00 0.13 0.00 42.48 0

Lodgepole and Woodland 0.15 0.13 8.52 0

Mixed Conifer Forest and 

Woodland

0.17 22.46 1.45 14.54 0.09 0.02 1.12 1459.56 3

Mixed Oak Woodland 0.26 0.01 0.06 0.21 0.00 60.25 0

Riparian 0.02 0.26 0.01 0.00 3.22 1.02 42.76 0

Sagebrush Shrubland 66.46 11.19 57.82 15.99 44.17 50.70 15.30 7.36 22582.73 48

Sagebrush Steppe 3.31 3.85 0.89 3.82 4.79 6.65 0.35 1137.61 2

Sparse Vegetation 0.02 7.75 21.78 0

Water 0.12 0.01 0.01 6.79 0
C-3

Table C1. % of Geographic Unit

General Biophysical Setting

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

White Pine-White Fir 

Woodland

0.17 0.02 0.02 9.71 0

Wooded Volcanic Flowage 0.04 0.00 0.67 0

Woodland 0.45 18.63 3.26 17.18 1460.33 3

Woodland and Chaparral 0.35 0.10 1.16 0.21 0.56 1.57 0.15 3.84 232.48 0

Woodland and Savanna 0.05 0.01 2.44 0

Woodland and Shrubland 0.02 0.16 0.04 0.80 0.05 28.11 0

Grand Total 100.0% 100.0% 100.0% 100.0% 100.1% 99.9% 100.0% 99.7% 46707.69 98%
C-4

Table C2. Vegetation succession classes: percentages by geographic unit (LANDFIRE 2008).

Table C2. % of Geographic Unit

Succession Class

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Succession Class A 0 17 1 4 0 1 1 0 742 2

Succession Class B 30 16 22 31 17 8 20 5 9759 26

Succession Class C 10 49 6 29 0 3 4 1 4536 12

Succession Class D 25 15 40 14 8 15 39 1 10257 27

Succession Class E 0 1 0 4 0 97 0

Uncharacteristic Native 

Vegetation Cover/ Structure/ 

Composition

0 0 0 0 0 1 41 0

Uncharacteristic Exotic 

Vegetation

34 1 31 17 75 73 35 93 12211 32

Total 100% 100% 100% 100% 100% 100% 100% 100% 37643 99%
C-5

Table C3. Fire regime groups: percentages by geographic unit (LANDFIRE 2008).

Table C3. % of Geographic Unit

Fire Regime Groups

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Fire Regime Group I 0 34 3 34 1643 4

Fire Regime Group II 0 2 0 2 112 0

Fire Regime Group III 99 57 97 63 99 75 91 32 35284 93

Fire Regime Group IV 1 4 1 1 1 16 1 16 495 1

Fire Regime Group V 0 3 0 9 8 52 445 1

Total 100% 100% 100% 100% 100% 100% 100% 100% 37979 99%
C-6

Table C4. Height classes of existing vegetation: percentages by geographic unit (LANDFIRE 2008).

Table C4. % of Geographic Unit

Existing Vegetation 

Height (m)

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Petroglyph 

Unit

#

Acres

% of 

Total

0-0.5 m shrubs 53.48 17.22 39.48 38.35 96.60 59.84 22.34 17024 48

0.5-1.0 m shrubs 44.60 5.78 50.94 5.03 2.82 39.88 76.35 14590 41

1.0-3.0 m shrubs 1.26 9.02 3.82 4.94 0.58 0.03 0.64 941 3

>3.0 m shrubs 0.00 0.13 0 0

0-5 m trees 0.03 0.00 1 0

5-10 m trees 0.18 17.93 0.97 5.74 0.16 0.21 733 2

10-25 m trees 0.48 50.02 4.79 45.94 0.08 0.34 2508 7

25-50 m trees 0.00 0.02 0 0

Total 100.00% 100.00% 100.00% 100.00% 100.00% 100.00% 100.00% 35798 101%
C-7

Table C5. Canopy classes of existing vegetation: percentages by geographic unit (LANDFIRE 2008).

Table C5. % of Geographic Unit

Existing 

Vegetation Canopy (%)

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

≥10 and <20 % Shrub 34 6 4 21 0 17 7 22 8157 22

≥10 and <20 % Forest 1 39 4 25 0 6 2051 5

≥20 and <30 % Herb 0 0 0

≥20 and <30 % Shrub 34 26 55 24 13 36 53 19 14502 39

≥20 and <30 % Forest 0 25 1 15 0 1 0 1060 3

≥30 and <40 % Shrub 31 0 35 3 87 46 33 58 11585 31

≥30 and <40 % Forest 0 2 0 6 0 0 0 146 0

≥40 and <50 % Shrub 0 0 0 0 5 0

≥40 and <50 % Forest 1 0 4 58 0

≥50 and <60 % Forest 0 0 2 0 27 0

≥60 and <70 % Forest 0 0 0 3 0

≥70 and <80 % Forest 0 0 0

Total 100% 100% 100% 100% 100% 100% 100% 100% 37594 100%
C-8

Table C6. Canopy cover: percentages by geographic unit (LANDFIRE 2008).

Table C6. % of Geographic Unit

Canopy Cover (%)

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Non-forested vegetation 99.55 59.31 95.70 69.63 100.00 99.80 99.17 99.58 43922.12 94.09

≥ 10% and < 20% 0.42 22.61 2.91 12.20 0.11 0.76 1589.46 3.40

≥ 20% and < 30% 0.02 15.93 1.22 8.68 0.07 0.07 0.11 943.57 2.02

≥ 30% and < 40% 0.00 1.60 0.16 4.52 0.02 0.00 0.21 140.90 0.30

≥ 40% and < 50% 0.44 0.01 2.98 55.58 0.12

≥ 50% and < 60% 0.09 0.01 1.84 0.00 0.11 26.22 0.06

≥ 60% and < 70% 0.00 0.02 0.13 2.65 0.01

≥ 70% and < 80% 0.02 0.22 0.00

Total 100% 100% 100% 100% 100% 100% 100% 100% 46680.75 100%
C-9

Table C7. Existing vegetation types: percentages by geographic unit (LANDFIRE 2008).

Table C7. % of Geographic Unit

Existing Vegetation Type

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

Agriculture-Cultivated Crops and 

Irrigated Agriculture

1.23 0.36 9.78 0.02

Agriculture-Pasture/Hay 0.00 1.05 0.88 0.01 4.98 30.81 0.07

Artemisia tridentata ssp. 

vaseyana Shrubland Alliance

0.01 0.08 0.09 0.55 0.26 0.00 23.41 0.05

Barren 1.64 30.93 5.94 16.77 0.66 0.20 77.44 1.30 8721.65 18.69

California Montane Jeffrey 

Pine(-Ponderosa Pine) 

Woodland

0.04 0.43 6.85 0.01

California Montane Woodland 

and Chaparral

0.17 0.11 0.08 0.58 0.37 1.96 0.01 0.11 74.92 0.16

Columbia Plateau Low 

Sagebrush Steppe

5.02 4.65 6.94 11.85 30.66 4.33 1.48 6.79 2557.59 5.48

Columbia Plateau Western 

Juniper Woodland and Savanna

0.02 2.39 0.04 1.66 0.09 140.58 0.30

Developed-High Intensity 0.00 0.22 0.00

Developed-Low Intensity 0.45 0.15 0.18 0.25 0.36 1.87 0.00 2.03 144.14 0.31

Developed-Medium Intensity 0.01 0.00 0.01 2.14 0.00

Developed-Open Space 0.02 0.08 0.14 0.76 0.20 0.00 32.07 0.07

Great Basin Semi-Desert 

Chaparral

0.26 0.00 0.01 0.06 0.25 0.00 60.65 0.13
C-10

Table C7. % of Geographic Unit

Existing Vegetation Type

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

Inter-Mountain Basins Big 

Sagebrush Shrubland

87.65 15.74 79.61 23.98 62.14 61.36 19.23 15.40 30078.51 64.47

Inter-Mountain Basins Big 

Sagebrush Steppe

3.04 0.22 0.01 1.53 3.66 4.55 0.18 761.66 1.63

Inter-Mountain Basins Curl-leaf 

Mountain Mahogany Woodland 

and Shrubland

0.00 0.16 0.00 0.84 0.06 22.39 0.05

Inter-Mountain Basins 

Greasewood Flat

0.67 0.01 21.73 56.51 422.83 0.91

Inter-Mountain Basins Mixed 

Salt Desert Scrub

0.02 0.03 0.03 5.06 0.01

Inter-Mountain Basins Montane 

Riparian Systems

0.00 0.22 0.01 0.22 0.11 13.25 0.03

Inter-Mountain Basins Montane 

Sagebrush Steppe

0.05 1.44 0.52 1.14 1.00 0.01 149.99 0.32

Inter-Mountain Basins Sparsely 

Vegetated Systems

0.02 7.97 22.05 0.05

Introduced Upland VegetationAnnual Grassland0.00 0.15 0.00

Juniperus occidentalis Wooded 

Herbaceous Alliance

0.11 1.33 0.00

Juniperus occidentalis

Woodland Alliance

0.11 2.81 0.79 7.89 0.22 335.97 0.72
C-11

Table C7. % of Geographic Unit

Existing Vegetation Type

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

Mediterranean California DryMesic Mixed Conifer Forest and 

Woodland

0.00 4.60 0.07 2.32 0.01 240.62 0.52

Mediterranean California Lower 

Montane Black Oak-Conifer 

Forest and Woodland

0.00 0.22 0.00

Mediterranean California Mesic 

Mixed Conifer Forest and 

Woodland

7.50 0.88 5.13 0.01 481.78 1.03

North Pacific Montane Riparian 

Woodland and Shrubland

0.32 0.67 0.00

North Pacific Wooded Volcanic 

Flowage

0.16 0.01 0.29 0.00 11.40 0.02

Northern and Central California 

Dry-Mesic Chaparral

0.34 1.08 0.11 0.53 1.48 0.14 3.96 214.82 0.46

Northern Rocky Mountain DryMesic Montane Mixed Conifer 

Forest

0.19 0.02 0.34 0.00 14.65 0.03

Northern Rocky Mountain 

Montane-Foothill Deciduous 

Shrubland

0.00 0.03 0.00 0.02 1.93 0.00

Northern Rocky Mountain 

Ponderosa Pine Woodland and 

Savanna

0.47 27.28 3.54 21.20 0.02 1.09 2000.59 4.29

Open Water 0.13 0.01 0.01 6.92 0.01
C-12

Table C7. % of Geographic Unit

Existing Vegetation Type

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

Rocky Mountain Aspen Forest 

and Woodland

0.00 0.22 0.00

Rocky Mountain Poor-Site 

Lodgepole Pine Forest

0.35 0.00 0.07 16.55 0.04

Sierra Nevada Subalpine 

Lodgepole Pine Forest and 

Woodland

0.00 0.58 0.01 0.99 0.01 39.86 0.09

Sierran-Intermontane Desert 

Western White Pine-White Fir 

Woodland

0.16 0.02 0.02 9.34 0.02

Total 100.0% 100.0% 100.0% 99.9% 99.9% 100.0% 100.0% 99.8% 46657.58 99.9%

Table C8. Environmental site potential: percentages by geographic unit (LANDFIRE 2008).

Table C8. % of Geographic Unit

Environmental Site Potential

Basalt 

and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Barren-Rock/Sand/Clay 1.60 30.57 5.88 16.91 0.47 0.21 77.60 1.23 8711.93 18.65

Open Water 0.00 0.11 0.01 0.00 0.00 0.00 0.01 0.00 6.20 0.01

California Montane Jeffrey 

Pine(-Ponderosa Pine) 

Woodland

0.00 0.28 0.09 1.37 0.00 0.00 0.02 0.00 38.84 0.08

California Montane Woodland 

and Chaparral

0.22 0.00 0.69 0.11 0.55 0.00 0.07 0.00 127.06 0.27
C-13

Table C8. % of Geographic Unit

Environmental Site Potential

Basalt 

and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Columbia Plateau Low 

Sagebrush Steppe

0.00 1.94 0.00 0.00 0.00 0.00 0.01 0.00 88.05 0.19

Columbia Plateau Western 

Juniper Woodland and Savanna

26.94 17.46 33.45 30.62 57.36 14.81 6.82 19.67 11411.22 24.43

Great Basin Semi-Desert 

Chaparral

0.27 0.38 1.10 0.03 5.09 0.00 0.04 0.00 235.86 0.50

Inter-Mountain Basins Big 

Sagebrush Shrubland

65.96 5.49 53.42 15.40 31.02 50.74 14.02 7.39 21545.86 46.13

Inter-Mountain Basins Big 

Sagebrush Steppe

3.25 0.00 0.00 1.65 3.56 6.65 0.16 0.00 810.98 1.74

Inter-Mountain Basins Curl-leaf 

Mountain Mahogany Woodland 

and Shrubland

0.01 0.00 0.03 0.00 0.00 0.00 0.00 0.00 6.66 0.01

Inter-Mountain Basins 

Greasewood Flat

0.65 0.00 0.01 0.00 0.00 22.75 0.00 59.07 434.40 0.93

Inter-Mountain Basins Mixed 

Salt Desert Scrub

0.02 0.00 0.00 0.00 0.02 0.03 0.00 0.00 4.78 0.01

Inter-Mountain Basins Montane 

Riparian Systems

0.02 0.26 0.01 0.00 0.00 3.22 0.00 1.03 42.73 0.09

Inter-Mountain Basins Montane 

Sagebrush Steppe

0.01 0.00 0.06 1.83 1.20 0.00 0.00 0.00 41.92 0.09
C-14

Table C8. % of Geographic Unit

Environmental Site Potential

Basalt 

and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Inter-Mountain Basins SemiDesert Shrub-Steppe0.00 0.00 0.00 0.00 0.40 0.00 0.00 0.00 3.90 0.01

Inter-Mountain Basins Sparsely 

Vegetated Systems

0.02 0.00 0.00 0.00 0.00 0.00 0.00 7.77 21.78 0.05

Mediterranean California DryMesic Mixed Conifer Forest and 

Woodland

0.19 14.28 0.39 9.92 0.09 0.00 0.39 0.00 866.59 1.86

Mediterranean California Mesic 

Mixed Conifer Forest and 

Woodland

0.00 20.76 2.68 9.06 0.00 0.00 0.06 0.00 1302.40 2.79

Mediterranean California Mixed 

Oak Woodland

0.26 0.00 0.01 0.06 0.21 0.00 0.00 0.00 60.25 0.13

North Pacific Wooded Volcanic 

Flowage

0.00 0.00 0.00 0.04 0.00 0.00 0.00 0.00 0.67 0.00

Northern and Central California 

Dry-Mesic Chaparral

0.13 0.00 0.39 0.00 0.00 1.57 0.07 3.85 90.47 0.19

Northern Rocky Mountain DryMesic Montane Mixed Conifer 

Forest

0.00 0.37 0.03 0.74 0.00 0.00 0.01 0.00 29.80 0.06

Northern Rocky Mountain 

Ponderosa Pine Woodland and 

Savanna

0.44 7.02 1.74 12.06 0.00 0.02 0.71 0.00 775.19 1.66

Rocky Mountain Poor-Site 

Lodgepole Pine Forest

0.00 0.91 0.00 0.07 0.00 0.00 0.00 0.00 41.63 0.09
C-15

Table C8. % of Geographic Unit

Environmental Site Potential

Basalt 

and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyph 

Unit

#

Acres

% of 

Total

Sierra Nevada Subalpine 

Lodgepole Pine Forest and 

Woodland

0.00 0.16 0.00 0.13 0.00 0.00 0.00 0.00 8.52 0.02

Grand Total 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 100.0% 46707.69 100%
C-16

Table C9. Estimated mean fire return intervals: percentages by geographic unit (LANDFIRE 2008).

Table C9 % of Geographic Unit

Estimated Mean Fire Return 

Interval

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

No defined fire behavior or 

extremely low probabilities of fire 

ignition

2 31 6 17 1 0 78 10 8813 19

16-20 Years 0 0 0 2 0 0 0 0 19 0

21-25 Years 0 1 1 7 0 0 0 0 198 0

26-30 Years 0 12 1 11 0 0 0 0 762 2

31-35 Years 0 12 0 11 0 0 0 0 752 2

36-40 Years 1 10 1 9 1 0 0 0 802 2

41-45 Years 4 6 3 8 6 0 2 0 1598 3

46-50 Years 11 4 12 7 8 0 2 0 4086 9

51-60 Years 37 6 32 11 23 10 6 0 12122 26

61-70 Years 15 5 13 8 19 23 2 0 5216 11

71-80 Years 9 4 6 4 16 22 2 0 3127 7

81-90 Years 7 2 4 3 14 10 1 0 2249 5

91-100 Years 5 1 3 1 7 4 1 0 1503 3

101-125 Years 8 2 9 1 6 11 3 0 2980 6

126-150 Years 2 1 7 0 0 5 1 12 1362 3

151-200 Years 1 1 2 0 0 6 1 34 629 1

201-300 Years 0 0 0 0 0 9 1 40 256 1
C-17

Table C9 % of Geographic Unit

Estimated Mean Fire Return 

Interval

Basalt and 

Andesite Basalt

Basaltic 

Andesite Buttes

Gillem 

Bluff

Historic 

Lake Bed

Lava 

Flows

Petroglyp

h Unit

#

Acres

% of 

Total

301-500 Years 0 1 0 0 0 0 0 4 63 0

501-1000 Years 0 0 0 0 0 0 0 0 51 0

>1000 Years 0 1 0 0 0 0 1 0 72 0

Most common Mean Fire Return 

Interval

51-60 yr None 51-60 yr None 51-60 yr 61-70 yr None 201-300 yr 46656 51-60 yr
C-18

Figure C1. Mapped biophysical classes of Lava Beds National Monument (LANDFIRE 2006). Scale: 30 meters. This map was prepared by other 

investigators who extrapolated information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in 

LANDFIRE workshops. The classes in this dataset represent the vegetation that may have been dominant on the landscape prior to EuroAmerican settlement and are based on both the current biophysical environment and an approximation of the historical disturbance regime.
C-19

Figure C2. Mapped existing vegetation in Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other investigators who 

extrapolated information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in LANDFIRE 

workshops.
C-20

Figure C3. Mapped successional classes in Lava Beds National Monument (LANDFIRE 2008). This map 

was prepared by other investigators who extrapolated information using Landsat Thematic Mapper and 

other data. Lands were assigned to map classes by experts in LANDFIRE workshops.
C-21

Figure C4. Mapped canopy cover of Lava Beds National Monument (LANDFIRE 2008). This map was 

prepared by other investigators who extrapolated information using Landsat Thematic Mapper and other 

data. Lands were assigned to map classes by experts in LANDFIRE workshops. 
C-22

Figure C5. Mapped existing vegetation height of Lava Beds National Monument (LANDFIRE 2008). This 

map was prepared by other investigators who extrapolated information using Landsat Thematic Mapper 

and other data. Lands were assigned to map classes by experts in LANDFIRE workshops.
C-23

Figure C6. Mapped canopy height of Lava Beds National Monument (LANDFIRE 2008). This map was 

prepared by other investigators who extrapolated information using Landsat Thematic Mapper and other 

data. Lands were assigned to map classes by experts in LANDFIRE workshops.
C-24

Figure C7. Mapped canopy base height of Lava Beds National Monument (LANDFIRE 2007). Scale: 30 meters. This map was prepared by other 

investigators who extrapolated information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in 

LANDFIRE workshops. The map describes the average height from the ground to the bottom of a forest stand's canopy; it is the lowest height at 

which there is a sufficient amount of forest canopy fuel to propagate fire vertically into the canopy. There is no universally accepted, empiricallyderived definition of canopy base height.
C-25

Figure C8. Mapped canopy bulk density of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other investigators who 

extrapolated information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in LANDFIRE 

workshops. 
C-26

Figure C9. Mapped environmental site potential of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other 

investigators who extrapolated Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in LANDFIRE 

workshops. 
C-27

Figure C10. Mapped fire regime condition classes of Lava Beds National Monument (LANDFIRE 2008). 

This map was prepared by other investigators who extrapolated fuels information using Landsat Thematic 

Mapper and other data. Lands were assigned to map classes by experts in LANDFIRE workshops. The 

map does not portray fuel, fuel arrangement, or vegetation flammability. The map was based on rough 

estimates of the level to which fire frequencies have departed from “natural” fire frequencies. FRCC is 

also not a measure of fire risk or hazard. Increasing FRCC may lead to either more or less severe fire. 

Nonetheless, FRCC may be useful to identify where fire should be allowed to burn. The natural fire 

regime of every ecosystem falls into only five classes for determining departure, but the fire regimes of 

this park do not fit this classification.
C-28

Figure C11. Mapped fire regime groups of Lava Beds National Monument (LANDFIRE 2008). This map 

was prepared by other investigators who extrapolated fuels information using Landsat Thematic Mapper 

and other data. Lands were assigned to map classes by experts in LANDFIRE workshops. The map does 

not portray fuel, fuel arrangement, or vegetation flammability.
C-29

Figure C12. Mapped mean fire return interval of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other investigators 

who extrapolated fuels information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts in LANDFIRE 

workshops. The map does not portray fuel, fuel arrangement, or vegetation flammability.
C-30

Figure C13. Mapped percent of replacement severity fires of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other 

investigators who extrapolated fuels information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts 

in LANDFIRE workshops. The map does not portray fuel, fuel arrangement, or vegetation flammability.
C-31

Figure C14. Mapped percent of low severity fires of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other 

investigators who extrapolated fuels information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts 

in LANDFIRE workshops. The map does not portray fuel, fuel arrangement, or vegetation flammability.
C-32

Figure C15. Mapped percent of mixed severity fires of Lava Beds National Monument (LANDFIRE 2008). This map was prepared by other 

investigators who extrapolated fuels information using Landsat Thematic Mapper and other data. Lands were assigned to map classes by experts 

in LANDFIRE workshops. The map does not portray fuel, fuel arrangement, or vegetation flammability.
C-33

Figure C16. Mapped fire history of Lava Beds National Monument (LANDFIRE 2008). 

D-1

Appendix D. Vertebrate Species Records From the Lava Beds 

Wildlife Observations Database

Note: The records in the following tables were not collected systematically and their accuracy 

has not been verified. Some records may have come from areas near but not in the monument. 

These lists are not comprehensive.
Table D1. Incidental observations of amphibians and reptiles, June 1960 to July 2012.

Note: The records in the following table were not collected systematically and their accuracy has not been 

verified. Some records may have come from areas near but not in the monument. These lists are not 

comprehensive.

Species Earliest Date Most Recent Date # of reports Maximum Count

AMPHIBIANS

Foothill Yellow-legged Frog 18-Nov-92 18-Nov-92 2 1

Pacific Treefrog 15-Aug-63 1-Apr-11 17 12

Rough-skinned Newt 23-Mar-03 23-Mar-03 1 1

Western Toad 29-Jul-71 11-May-05 6 1

REPTILES

Garter Snake 3-May-98 2-Oct-07 7 1

Gopher Snake 9-Apr-61 8-Jul-12 65 1

Night Snake 23-Jun-67 24-Jun-09 34 1

Northern Alligator Lizard 27-Jun-64 21-May-09 8 1

Northern Rubber Boa 19-Jun-60 30-Jul-09 78 1

Racer 3-Aug-60 23-May-12 27 3

Ringneck Snake 7-Sep-68 7-Sep-68 2 1

Striped Whipsnake 7-Aug-60 5-Sep-95 23 1

Western Fence Lizard 6-Aug-62 20-Aug-09 13 10

Western Rattlesnake 24-Jul-60 27-Jun-12 176 3

Western Skink 25-Aug-62 9-Jun-10 45 1

Western Whiptail 17-Jul-93 17-Jul-93 2 1

Western Yellow-bellied Racer 26-May-62 1-Oct-11 2 1
D-3

Table D2. Incidental observations of mammals, June 1943 to July 2012.

Note: The records in the following table were not collected systematically and their accuracy has not been 

verified. Some records may have come from areas near but not in the monument. These lists are not 

comprehensive.

Species Earliest Date Most Recent Date # of reports Maximum Count

American Badger 11-Oct-60 23-Jul-12 56 3

American Marten 9-Aug-65 9-Aug-65 1 1

American Pika 15-May-60 20-Jun-12 117 3

Belding's Ground Squirrel 24-May-60 5-Jun-08 32 15

Big Brown Bat 17-Jul-63 21-Jul-71 3 1

Bighorn Sheep 17-Aug-72 10-Oct-73 25 17

Black Bear 26-May-85 3-Jun-05 11 1

Black-tailed Jackrabbit 22-Sep-60 10-Oct-09 81 28

Bobcat 19-May-60 25-Jul-12 351 5

Bushy-tailed Woodrat 29-May-61 25-Aug-09 29 6

California Ground Squirrel 20-Jul-61 15-Sep-04 53 8

California Kangaroo Rat 13-Dec-07 13-Dec-07 2 1

California Mole 31-Oct-70 14-Jun-92 7 1

California Myotis 12-Jul-63 12-Jul-63 1 1

Canyon Mouse 27-Jul-81 27-Jul-81 4 4

Cougar 1-Jul-60 8-Apr-11 166 4

Coyote 25-Jun-43 23-Jul-12 403 8

Douglas Squirrel 7-Jul-61 6-May-08 14 3

Dusky-footed Woodrat 28-Oct-61 8-Jul-12 20 3

Elk (Wapiti) 25-Jun-06 19-Feb-10 6 30

Fringed myotis 25-Apr-04 25-Apr-04 1 1

Golden-mantled Ground Squirrel 11-Nov-61 22-May-94 35 7

Gray Fox 28-Aug-75 13-Jul-12 19 2

Great Basin Pocket Mouse 6-Apr-62 27-Jul-81 6 3

Heermann Kangaroo Rat 6-Feb-92 20-Aug-92 3 5

Kangaroo Rat 31-May-60 15-Mar-08 25 40
D-4

Species Earliest Date Most Recent Date # of reports Maximum Count

Kit Fox 31-May-88 29-Jun-89 3 1

Least Chipmunk 6-Apr-62 11-Jul-04 11 4

Little Brown Myotis 10-Jul-73 18-Aug-89 3 4

Long-eared Bat 7-Aug-02 27-Mar-03 2 1

Long-tailed Weasel 12-Jun-60 2-Dec-08 61 3

Mountain Cottontail 22-Sep-60 19-Dec-04 83 14

Mountain Goat 1-Jan-70 1-Jan-70 2 1

Mule Deer 2-May-60 27-Jun-12 442 52

Pallid Bat 17-Jul-63 23-Jul-70 3 300

Pinyon Mouse 5-Apr-62 27-Jul-81 6 2

Porcupine 27-Jun-60 29-Oct-97 179 7

Pronghorn (Antelope) 5-May-60 13-May-11 357 150

Raccoon 11-Sep-63 2-Aug-11 33 5

Red Fox 24-Sep-80 26-Mar-10 7 4

Ringtail 12-Aug-91 12-Aug-91 3 1

River Otter 10-Dec-91 6-Jun-06 4 3

Short-tailed Weasel 25-Aug-92 18-Jun-09 8 1

Small-footed Myotis 19-Jul-63 19-Jul-63 1 1

Spotted Skunk 11-Oct-61 2-Sep-97 11 2

Striped Skunk 18-Aug-60 16-May-10 23 1

Townsend's Big-eared Bat 22-Jun-61 1-Jul-08 21 300

Townsend's Chipmunk 5-Aug-86 6-Aug-86 4 4

Trowbridge Shrew 16-May-62 29-Jul-81 5 1

Western Gray Squirrel* * * * *

Western Harvest Mouse 27-Jul-81 28-Jul-81 4 2

White-footed Deer Mouse 16-Feb-62 3-Feb-68 4 50

Yellow Pine Chipmunk 7-Nov-61 1-Oct-04 22 13

Yellow-bellied Marmot 4-Mar-61 13-Nov-07 132 10

* recorded by remote wildlife camera
D-5

Table D3. Incidental observations of birds, February 1952 to July 2012 (209 species).

Note: The records in the following table were not collected systematically and their accuracy has not been 

verified. Some records may have come from areas near but not in the monument. These lists are not 

comprehensive.

Species Earliest Year Most Recent Year # of reports Maximum Count

Allen's Hummingbird 30-Jun-68 8-Jul-70 5 1

American Bittern 29-Jul-72 29-Jul-72 1 1

American Coot 8-Apr-62 17-Dec-72 5 4

American Kestrel 15-Jul-70 16-Jul-12 23 5

American Robin 5-Jun-61 23-Jan-07 36 20

American White Pelican 11-Apr-62 8-Jul-92 6 50

American Wigeon 31-Aug-72 20-Sep-97 4 3

Anna's Hummingbird 20-Jul-70 16-Apr-10 15 1

Ash-throated Flycatcher 25-Jun-60 22-Jun-92 26 2

Bald Eagle 9-Nov-60 13-Jun-12 233 20

Bank Swallow 31-Jul-72 31-Jul-72 3 1

Barn Owl 26-Nov-60 25-Jun-12 81 20

Barn Swallow 19-Aug-62 22-May-98 14 5

Belted Kingfisher 18-Dec-72 18-Dec-72 2 1

Bewick's Wren 8-Feb-53 23-Jan-07 17 3

Black Swift 7-Jul-72 7-Jul-72 2 1

Black Tern 19-Jul-72 1-May-98 8 200

Black-backed Woodpecker 14-Apr-98 14-Dec-07 12 2

Black-billed Magpie 5-Jun-57 7-Jan-08 50 10

Black-capped Chickadee 21-May-89 21-May-89 1 1

Black-chinned Hummingbird 6-Jun-87 6-Jun-87 1 1

Black-chinned Sparrow 31-May-91 31-May-91 2 1

Black-crowned Night Heron 27-Jun-72 17-Dec-72 2 3

Black-headed Grosbeak 7-Aug-73 23-May-09 9 3

Black-necked Stilt 27-Jul-72 31-Jul-72 6 26

Black-throated Gray Warbler 20-Aug-62 20-Aug-62 3 1
D-6

Species Earliest Year Most Recent Year # of reports Maximum Count

Black-throated Sparrow 22-Jun-68 2-Jul-07 6 2

Blue-gray Gnatcatcher 25-Sep-62 5-May-98 17 5

Blue-winged Teal 22-Jun-72 9-Jun-87 3 2

Bohemian Waxwing 25-Feb-87 17-Feb-97 4 20

Bonaparte's Gull 23-Apr-63 23-Apr-63 1 2

Brant 16-Apr-63 16-Apr-63 1 1

Brewer's Blackbird 28-Feb-52 8-Jul-92 42 60

Brewer's Sparrow 29-Jul-62 29-Jul-62 2 1

Broad-tailed Hummingbird 15-Jun-70 12-May-98 4 2

Brown Creeper 20-Oct-63 24-Mar-65 4 1

Brown-headed Cowbird 28-May-62 2-May-96 11 15

Bufflehead 29-Sep-97 20-Oct-97 4 10

Bullock's Oriole 15-May-61 20-May-12 32 6

Burrowing Owl 1-Jul-73 2-Mar-04 14 2

Bushtit 28-Jun-52 6-Apr-04 28 100

California Quail 24-May-60 1-Nov-94 154 131

California Towhee 4-Jul-85 20-Dec-02 13 1

Calliope Hummingbird 19-Jun-66 26-Jun-07 11 2

Canada Goose 14-Feb-61 22-Apr-10 14 999

Canvasback 11-Apr-62 11-Apr-62 2 0

Canyon Towhee 28-Nov-90 28-Nov-90 2 3

Canyon Wren 4-Oct-52 16-Jul-09 46 6

Caspian Tern 23-Apr-63 19-Jun-72 3 3

Cassin's Finch 4-Apr-63 17-Aug-92 16 13

Cedar Waxwing 6-Jun-59 20-Feb-09 33 100

Chipping Sparrow 22-Apr-63 10-Aug-73 8 3

Chukar 14-Apr-60 9-Jul-93 14 25

Clark's Grebe 20-Sep-97 20-Sep-97 2 2

Clark's Nutcracker 5-Jul-58 11-May-10 28 8
D-7

Species Earliest Year Most Recent Year # of reports Maximum Count

Cliff Swallow 1-Jun-62 30-Jun-04 9 300

Common Loon 21-May-63 21-May-63 2 1

Common Merganser 9-Jun-87 9-Jun-87 1 1

Common Nighthawk 7-May-60 16-Jul-09 33 8

Common Poorwill 25-Jun-60 26-May-09 19 1

Common Raven 29-Aug-52 12-Apr-06 82 9

Common Redpoll 28-Feb-89 28-Feb-89 2 2

Cooper's Hawk 22-Apr-63 1-Oct-04 13 2

Costa's Hummingbird 10-May-92 1-Jun-00 13 1

Dark-eyed Junco 24-May-60 1-Oct-04 22 40

Double-crested Cormorant 23-Apr-63 28-Apr-88 5 150

Downy Woodpecker 23-Jul-96 23-Jul-96 2 1

Dusky Flycatcher 12-Aug-72 12-Aug-72 3 1

Eurasian Collared-Dove 17-Jul-07 17-May-11 5 1

European Starling 26-Apr-65 30-Nov-66 3 10

Evening Grosbeak 10-Apr-61 19-Apr-11 18 22

Ferruginous Hawk 19-Feb-98 3-Aug-98 4 2

Flammulated Owl 22-May-03 22-May-03 2 1

Forster's Tern 25-Apr-62 19-Jul-72 5 50

Fox Sparrow 15-Oct-92 26-Sep-03 6 1

Gadwall 3-Jul-62 3-Jul-62 1 26

Golden Eagle 31-Jul-60 25-Jul-12 89 4

Golden-crowned Kinglet 23-Apr-63 18-Nov-93 3 9

Golden-crowned Sparrow 3-May-91 20-Sep-97 8 3

Gray Flycatcher 20-Aug-62 20-Aug-62 2 1

Great Blue Heron 14-Feb-61 14-Dec-92 8 7

Great Egret 7-Jul-72 20-Sep-97 5 40

Great Grey Owl 2-Aug-92 2-Aug-92 2 1

Great Horned Owl 22-Sep-60 3-Jul-12 61 5
D-8

Species Earliest Year Most Recent Year # of reports Maximum Count

Greater White-fronted Goose 30-Sep-97 20-Oct-97 4 999

Greater Yellowlegs 8-Apr-63 8-Jul-72 3 30

Green-tailed Towhee 26-Jun-72 30-Jun-96 10 3

Gyrfalcon 25-May-87 9-Nov-89 4 1

Hairy Woodpecker 25-Aug-52 6-Aug-72 9 2

Hammond's Flycatcher 20-Sep-97 20-Sep-97 2 1

Harris' Sparrow 27-Mar-95 27-Mar-95 2 1

Hermit Thrush 21-Oct-97 21-Oct-97 2 2

Hermit Warbler 20-Aug-62 12-Aug-72 6 2

Horned Grebe 15-Apr-63 15-Apr-63 1 2

Horned Lark 16-Dec-52 1-Feb-08 20 70

House Finch 23-Apr-63 8-Jul-92 7 4

House Sparrow 22-Jul-72 22-Jul-72 2 3

House Wren 24-Apr-61 24-Apr-61 3 1

Killdeer 3-Jul-62 28-Jul-73 3 5

Lark Sparrow 8-Apr-63 17-Jun-98 11 23

Lazuli Bunting 30-Jun-65 30-May-09 20 2

Least Sandpiper 19-Jul-72 22-Apr-98 4 20

Lesser Goldfinch 16-Sep-60 21-Jul-72 8 2

Lesser Scaup 17-Dec-72 17-Dec-72 2 3

Lewis's Woodpecker 11-May-62 10-Jul-07 57 3

Lincoln's Sparrow 7-Jan-04 7-Jan-04 2 1

Loggerhead Shrike 9-Apr-62 18-Nov-93 41 2

Long-billed Curlew 14-Jul-71 14-Jul-71 2 3

Long-billed Dowitcher 31-Jul-68 8-Jul-72 4 10

Long-eared Owl 2-Mar-04 2-Mar-04 2 1

MacGillivray's Warbler 3-Aug-66 17-Aug-72 8 1

Mallard 8-Apr-62 20-Oct-97 4 999

Marbled Godwit 19-Jul-72 19-Jul-72 2 50
D-9

Species Earliest Year Most Recent Year # of reports Maximum Count

Marsh Wren 20-Sep-97 20-Sep-97 2 1

Merlin 12-Aug-66 4-Nov-08 8 1

Mountain Bluebird 12-Mar-53 17-Jul-11 36 20

Mountain Chickadee 23-Apr-63 29-Apr-98 26 4

Mountain Quail 15-Aug-61 28-Aug-07 41 30

Mourning Dove 5-May-60 16-Jul-12 16 115

Nashville Warbler 5-Aug-71 17-Aug-72 12 1

Northern Flicker 1-Apr-62 15-Oct-07 25 2

Northern Goshawk 1-Oct-75 2-Feb-07 17 1

Northern Harrier 5-Sep-60 6-Oct-03 35 5

Northern Mockingbird 24-Apr-68 17-Oct-97 6 2

Northern Pygmy-owl 8-Oct-65 22-Jan-07 22 1

Northern Saw-whet Owl 15-Oct-70 14-Mar-04 22 1

Northern Shoveler 11-Apr-62 20-Oct-97 4 30

Northern Shrike 13-Nov-70 12-Feb-08 15 1

Olive-sided Flycatcher 5-Jul-58 27-Jul-62 3 1

Orange-crowned Warbler 3-Sep-68 20-Sep-97 7 5

Osprey 13-Sep-98 13-Sep-98 2 1

Pacific (Winter) Wren 14-Mar-04 14-Mar-04 2 1

Peregrine Falcon 7-Apr-62 4-Jul-08 28 2

Pied-billed Grebe 28-Jul-72 20-Sep-97 4 10

Pileated Woodpecker 3-May-05 3-May-05 2 1

Pine Grosbeak 10-Mar-89 20-May-98 4 2

Pine Siskin 7-Jun-92 26-Nov-92 6 30

Pinyon Jay 15-Jan-53 4-May-08 76 100

Plain Titmouse 17-Dec-52 13-Feb-06 29 3

Prairie Falcon 7-Jan-62 28-Mar-08 119 7

Purple Finch 27-Apr-62 29-Jul-92 10 6

Purple Martin 14-May-57 17-Apr-08 63 100
D-10

Species Earliest Year Most Recent Year # of reports Maximum Count

Pygmy Nuthatch 3-Jan-53 18-Jun-00 12 20

Red Crossbill 5-Oct-62 19-May-09 34 25

Red Knot 5-May-71 5-May-71 2 1

Red-breasted Nuthatch 7-Sep-62 20-Oct-92 16 2

Red-breasted Sapsucker 31-May-61 6-May-03 21 1

Redhead 31-Aug-72 31-Aug-72 1 1

Red-naped Sapsucker 21-Sep-97 21-Sep-97 2 4

Red-shouldered Hawk 7-Aug-93 7-Aug-93 2 1

Red-tailed Hawk 10-May-60 21-Jul-11 92 8

Red-winged Blackbird 11-Apr-62 1-Jul-92 3 40

Ring-billed Gull 28-Jul-72 15-Jun-92 6 16

Ring-necked Pheasant 27-May-60 11-Jul-12 68 308

Rock Wren 15-May-57 10-Nov-02 24 8

Rough-legged Hawk 22-Mar-61 10-Apr-08 23 6

Ruby-crowned Kinglet 21-Apr-63 21-Apr-63 3 2

Ruffed Grouse 8-Aug-67 6-Aug-69 4 8

Rufous Hummingbird 18-Aug-62 19-Apr-98 24 4

Rufous-crowned Sparrow 18-May-67 18-May-67 2 1

Sage Grouse 18-Aug-60 11-Sep-08 31 10

Sage Thrasher 3-May-63 9-Feb-04 16 6

Sandhill Crane 19-Oct-87 12-Nov-10 8 106

Savannah Sparrow 8-Apr-63 8-Apr-63 1 2

Say's Phoebe 21-Apr-62 2-Mar-10 36 7

Sharp-shinned Hawk 9-Apr-62 21-Oct-03 11 2

Short-eared Owl 25-May-62 6-Feb-08 32 39

Snow Goose 15-Dec-60 29-Oct-03 10 999

Snowy Egret 20-Jul-72 20-Jul-72 1 1

Snowy Owl 28-Nov-66 28-Nov-66 2 1

Sooty (Blue) Grouse 10-Aug-60 18-Jun-11 35 5
D-11

Species Earliest Year Most Recent Year # of reports Maximum Count

Spotted Sandpiper 16-Jul-72 20-Sep-97 4 1

Spotted Towhee 24-May-60 14-Oct-94 27 2

Steller's Jay 20-Dec-52 1-Oct-04 20 5

Swainson's Hawk 10-Aug-60 12-Sep-01 8 1

Townsend's Solitaire 25-Oct-59 1-Oct-04 32 17

Townsend’s Warbler 20-Aug-68 20-Aug-68 3 1

Tree Swallow 2-May-61 23-Jun-72 8 10

Tricolored Blackbird 23-Apr-63 23-Apr-63 1 200

Tundra Swan 15-Dec-60 29-Oct-92 8 200

Turkey Vulture 26-Apr-62 13-Mar-07 27 30

Varied Thrush 3-Nov-60 28-Oct-02 14 1

Vaux's Swift 8-Sep-70 8-Sep-70 2 6

Vesper Sparrow 9-Apr-62 17-Apr-06 6 50

Violet-green Swallow 14-May-57 29-Jun-01 17 10

Warbling Vireo 22-Aug-70 22-Aug-70 3 1

Western Bluebird 9-Apr-57 3-May-10 36 20

Western Grebe 11-Apr-62 11-Apr-62 1 10

Western Kingbird 30-Jun-52 19-Apr-09 24 3

Western Meadowlark 14-Apr-62 23-Mar-10 17 15

Western Sandpiper 20-Aug-68 19-Jul-72 4 100

Western Scrub-Jay 13-Apr-61 4-Apr-08 61 10

Western Tanager 22-May-60 18-Jun-12 33 5

Western Wood-Pewee 16-Aug-68 6-Feb-89 9 1

White-breasted Nuthatch 19-Nov-60 23-Sep-10 12 20

White-crowned Sparrow 12-Apr-62 13-Sep-07 19 25

White-headed Woodpecker 19-Jun-72 3-Nov-02 9 4

White-throated Sparrow 28-Apr-70 28-Apr-70 1 1

White-throated Swift 14-Jun-98 22-Apr-10 9 13

Wild Turkey 7-Aug-08 13-May-10 10 8
D-12

Species Earliest Year Most Recent Year # of reports Maximum Count

Willet 16-Apr-63 16-Apr-63 1 0

Williamsons Sapsucker 1-Oct-62 3-Nov-02 9 1

Wilson's Phalarope 19-Jul-72 29-Jul-72 4 75

Wilson's Warbler 3-Aug-73 9-May-07 8 2

Wood Duck 19-Apr-98 5-Apr-07 4 2

Yellow Warbler 20-Aug-62 17-Jun-08 24 2

Yellow-headed Blackbird 15-May-61 22-Jul-92 8 30

Yellow-rumped Warbler 26-Apr-62 2-Apr-08 41 8
The Department of the Interior protects and manages the nation’s natural resources and cultural heritage; provides scientific 

and other information about those resources; and honors its special responsibilities to American Indians, Alaska Natives, and 

affiliated Island Communities.

NPS 147/122761, November 2013
National Park Service

U.S. Department of the Interior

Natural Resource Stewardship and Science

1201 Oakridge Drive, Suite 150

Fort Collins, CO 80525

www.nature.nps.gov

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