ABSTRACT
Data describing landscape history, particularly the response of landscape patterns to past climate and land uses, can improve results from models that predict patterns of species distributions. We assessed the influence of past climate,... more
Data describing landscape history, particularly the response of landscape patterns to past climate and land uses, can improve results from models that predict patterns of species distributions. We assessed the influence of past climate, past and current land use, and topography on the potential spatial and temporal distributions of terrestrial vertebrates in a semi-arid watershed using multitemporal satellite imagery, geospatial land ownership data, and long-term climate and vegetation monitoring data. We mapped decadal vegetation and land cover (1979, 1989, 1999, and 2009) using satellite and field data, and created species richness maps for each date using SWReGAP species-habitat models. Our results show that vegetation types with the highest mammal and avian species richness, primarily desert grasslands (mammal) and riparian vegetation (avian) types, experienced the largest change in land cover area and related species richness numbers over time. Change patterns were neither temp...
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Habitat heterogeneity is necessary to support reptile species diversity and abundance. In the North American Desert Southwest, there is little information regarding habitat preferences that influence reptile community occupancy. In south... more
Habitat heterogeneity is necessary to support reptile species diversity and abundance. In the North American Desert Southwest, there is little information regarding habitat preferences that influence reptile community occupancy.
In south central New Mexico, we sampled reptiles on Holloman Air Force Base (HAFB) in relatively undisturbed habitat
within gypsum sand dunes and clay/loamy soil to determine species richness and relative abundance using Occupancy
Modeling. Species were intensively surveyed using pitfall traps, funnels traps, road cruising and active searching. We
found six species of lizards, five species of snakes, and one turtle; lizards being more abundant, particularly the Common
Side-blotched (Uta stansburiana) and Little Striped Whiptail (Aspidoscelis inornata) lizards. We also related reptile
species assemblages to habitat gradients (cover and soil type) using Canonical Correspondence Analysis (CCA). Uta
stansburiana, A. inornata, and Eastern Collared Lizards (Crotaphytus collaris) were the only reptiles observed at a high
enough frequency to analyze their habitat associations using CCA. Uta stansburiana had a close association with bare
ground, A. inornata was associated with clay/loamy soil, and C. collaris was most closely associated with greater densities
of grasses and forbs. There may be confounding influences on the lack of reptile species detected, most notably precipitation, given persistent drought conditions in the Desert Southwest. After rain events resume, it may be necessary to re-examine reptile composition and their habitat associations to investigate the re-establishment and recruitment abilities of these arid-adapted species.
In south central New Mexico, we sampled reptiles on Holloman Air Force Base (HAFB) in relatively undisturbed habitat
within gypsum sand dunes and clay/loamy soil to determine species richness and relative abundance using Occupancy
Modeling. Species were intensively surveyed using pitfall traps, funnels traps, road cruising and active searching. We
found six species of lizards, five species of snakes, and one turtle; lizards being more abundant, particularly the Common
Side-blotched (Uta stansburiana) and Little Striped Whiptail (Aspidoscelis inornata) lizards. We also related reptile
species assemblages to habitat gradients (cover and soil type) using Canonical Correspondence Analysis (CCA). Uta
stansburiana, A. inornata, and Eastern Collared Lizards (Crotaphytus collaris) were the only reptiles observed at a high
enough frequency to analyze their habitat associations using CCA. Uta stansburiana had a close association with bare
ground, A. inornata was associated with clay/loamy soil, and C. collaris was most closely associated with greater densities
of grasses and forbs. There may be confounding influences on the lack of reptile species detected, most notably precipitation, given persistent drought conditions in the Desert Southwest. After rain events resume, it may be necessary to re-examine reptile composition and their habitat associations to investigate the re-establishment and recruitment abilities of these arid-adapted species.
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We studied winter habitat use of Ferruginous Hawks (Buteo regalis) from November 1999- February 2000 in southern New Mexico and northern Mexico by comparing vegetation in New Mexico among three potential hawk habitat types: occupied... more
We studied winter habitat use of Ferruginous Hawks (Buteo regalis) from November 1999- February 2000 in southern New Mexico and northern Mexico by comparing vegetation in New Mexico among three potential hawk habitat types: occupied black-tailed prairie dog (Cyn0mys ludovicianus) col- onies (N = 13), areas without prairie dogs that had historical records of occurrence (N = 7), and general
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The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited... more
The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited distributions, some of which are increasingly threatened by changing land uses. We assessed the impacts of two future urban growth scenarios on biodiversity in a binational watershed in Arizona, USA and Sonora, Mexico. We quantified and mapped terrestrial vertebrate species richness using Wildlife Habitat Relation models and validated the results with data from National Park Service (NPS) biological inventories. Future urban growth, based on historical trends, was projected to the year 2050 for (1) a ‘Current Trends’ (CT) scenario and (2) a ‘Megalopolis’ (MEGA) scenario that represented a transnational growth corridor with open-space conservation attributes. Based on CT, 45% of existing riparian woodland (267 of 451species) and 34% of semi-desert grasslands (215 of 451 species) will be lost, whereas in the MEGA scenario, these types would decline by 44% and 24%, respectively. Outcomes of the two models suggest a trade-off at the taxonomic class level: CT would reduce and fragment mammal and herpetofauna habitat, while MEGA would result in loss of avian-rich riparian habitat.
Ecosystem services, i.e., services provided to humans from ecological systems have become a key issue of this century in resource management, conservation planning, and environmental decision analysis. Mapping and quantifying ecosystem... more
Ecosystem services, i.e., services provided to humans from ecological systems have become a key issue of this century in resource management, conservation planning, and environmental decision analysis. Mapping and quantifying ecosystem services have become strategic national interests for integrating ecology with economics to help understand the effects of human policies and actions and their subsequent impacts on both ecosystem function and human well-being. Some aspects of biodiversity are valued by humans in varied ways, and thus are important to include in any assessment that seeks to identify and quantify the benefits of ecosystems to humans. Some biodiversity metrics clearly reflect ecosystem services (e.g., abundance and diversity of harvestable species), whereas others may reflect indirect and difficult to quantify relationships to services (e.g., relevance of species diversity to ecosystem resilience, cultural value of native species). Wildlife habitat has been modeled at broad spatial scales and can be used to map a number of biodiversity metrics. In the present study, we present an approach that (1) identifies mappable biodiversity metrics that are related to ecosystem services or other stakeholder concerns, (2) maps these metrics throughout a large multi-state region, and (3) compares the metric values obtained for selected watersheds within the regional context. The broader focus is to design a flexible approach for mapping metrics to produce a national-scale product. We map 20 biodiversity metrics reflecting ecosystem services or other aspects of biodiversity for all vertebrate species except fish. Metrics include species richness for all vertebrates, specific taxon groups, harvestable species (i.e., upland game, waterfowl, furbearers, small game, and big game), threatened and endangered species, and state-designated species of greatest conservation need, and also a metric for ecosystem (i.e., land cover) diversity. The project is being conducted at multiple scales in a phased approach, starting with place-based studies, then multi-state regional areas, culminating into a national-level atlas. As an example of this incremental approach, we provide results for the southwestern United States (i.e., states of Arizona, New Mexico, Nevada, Utah, and Colorado) and portions of two watersheds within this region: the San Pedro River (Arizona) and Rio Grande River (New Mexico). Geographic patterns differed considerably among metrics across the southwestern study area, but metric values for the two watershed study areas were generally greater than those for the southwestern region as a whole.
We modeled current and future distribution of suitable habitat for the talus-obligate montane mammal Ochotona princeps (American pika) across the western USA under increases in temperature associated with contemporary climate change, to:... more
We modeled current and future distribution of suitable habitat for the talus-obligate montane mammal Ochotona princeps (American pika) across the western USA under increases in temperature associated with contemporary climate change, to: a) compare forecasts using only climate variables vs using those plus habitat considerations; b) identify possible patterns of range collapse (center vs margins, and large- vs small-sized patches); and c) compare conservation and management implications of changes at two taxonomic resolutions, and using binned- vs binary-probability maps. We used MaxEnt to analyze relationships between occurrence records and climatic variables to develop a bioclimatic-envelope model, which we refined by masking with a deductive appropriate-habitat filter based on suitable land-cover types. We used this final species-distribution model to predict distribution of suitable habitat under range-wide temperature increases from 1 to 7°C, in 1°C increments; we also compared these results to distribution under IPCC-forecasted climates for 2050 and 2080. Though all currently recognized lineages and traditionally defined subspecies were predicted to lose increasing amounts of habitat as temperatures rose, the most-dramatic range losses were predicted to occur among traditional subspecies. Nineteen of the 31 traditional US pika subspecies were predicted to lose > 98% of their suitable habitat under a 7˚C increase in the mean temperature of the warmest quarter of the year, and lineages were predicted to lose 88 95% of suitable habitat. Under a 4˚C increase, traditional subspecies averaged a predicted 73% (range = 44–99%) reduction. The appropriate-habitat filter removed 40–6% of the predicted climatically suitable pixels, in a stepped and monotonically decreasing fashion as predicted temperatures rose. Predicted range collapse proceeded until only populations in island-biogeographic ‘mainlands’ remained, which were not in the geographic range center. We used this model system to illustrate possible distributional shifts under stepped changes in biologically relevant aspects of climate, importance of land cover and taxonomic level in species-distribution forecasts, and impact of using a single threshold vs multiple categories of persistence probability in predicted range maps; we encourage additional research to further investigate the generality of these patterns.
Effects of future land use change on watersheds have important management implications. Seamless, national-scale land-use-change scenarios for developed land were acquired from the U.S. Environmental Protection Agency Integrated Climate... more
Effects of future land use change on watersheds have important management implications. Seamless, national-scale land-use-change scenarios for developed land were acquired from the U.S. Environmental Protection Agency Integrated Climate and Land Use Scenarios (lCLUS) project and extracted to fit the South Platte River Basin, Colorado, relative to projections of housing density for the period 2000 through 2100. Habitat models developed from the Southwest Regional Gap Analysis Project were invoked to examine changes in wildlife habitat and biodiversity metrics using five ICLUS scenarios. The scenarios represent a U.S. Census base-case and four modifications that were consistent with the different assumptions underlying the A1, A2, B1, B2 Intergovernmental Panel on Climate Change global greenhouse gas emission storylines. Habitat models for terrestrial vertebrate species were used to derive metrics reflecting ecosystem services or biodiversity aspects valued by humans that could be quantified and mapped. Example metrics included richness of species of greatest conservation need, threatened and endangered species, harvestable species (e.g., upland game, big game), and total vertebrate species. Overall, the defined scenarios indicated that housing density and extent of developed lands will increase throughout the century with a resultant decrease in area for all species richness categories. The A2 Scenario in general showed greatest effect on area by species richness category. Areas with low or high species richness were projected to experience the greatest declines. The integration of the land use scenarios with biodiversity metrics derived from deductive habitat models may prove to be an important tool for decisionmakers involved in impact assessments and adaptive planning processes.
Landscape scale conservation planning efforts have been in place for the past several decades to maintain biodiversity. Objectives of past efforts have been to identify areas to create reserves based on species diversity, land ownership,... more
Landscape scale conservation planning efforts have been in place for the past several decades to maintain biodiversity. Objectives of past efforts have been to identify areas to create reserves based on species diversity, land ownership, and landscape context. Risk analysis has not often been included in these spatial analyses. Datasets such as the Southwest Regional Gap Analysis (SWReGAP) are now available as are processes that allow risk analysis to be viewed in a spatial context in relations to factors that affect habitats over broad scales. We describe a method to include four spatial datasets to provide coarse scale delineation on areas to focus conservation including species numbers, key habitats, land management and factors that influence habitats. We used the SWReGAP management status dataset to identify management categories for long-term intent of management for biodiversity. The New Mexico Department of Game and Fish identified a set of 290 Species of Greatest Conservation Need (SGCN). Species occurrences for these species were associated with hydrologic unit codes from the National Hydrography Dataset (NHD). Key habitats were identified by using the SWReGAP land cover dataset and NHD derivatives. Factors that influence habitats were identified and scored for 89 land cover types and 23 aquatic habitats identified by the NMDGF. Our final model prioritizes landscapes that are within key habitats, have high numbers of terrestrial and aquatic Species of Greatest Conservation Need taxa, may be potentially altered by multiple effects that influence habitats, and lack long-term legally-binding management plans protecting them from anthropogenic degradation. Similar to other efforts, riparian and aquatic habitats were identified as the most important for conservation. This information may be displayed spatially, allowing land managers and decision makers to understand the ecological context where multiple effects of potential factors may influence some habitats greater than others, and repeat process with CWCS revisions.
"Grazing lands are the most dominant land cover type in the United States, with approximately 311.7 Mha being defined as rangelands (Mitchell 2000). Approximately 53% (166.2 Mha) of the nation’s rangelands (USDA 2009) are owned and... more
"Grazing lands are the most dominant land cover type in the United States, with approximately 311.7 Mha being defined as rangelands (Mitchell 2000). Approximately 53% (166.2 Mha) of the nation’s rangelands (USDA 2009) are owned and managed by the private sector, while approximately 43% are managed
by the federal government (USDA NRCS 2011a). The remaining rangelands are owned and managed by tribal, state, and local governments. Information on the type, extent, and spatial location of land degradation on rangelands is needed to inform policy and management decisions on rangelands; however, there is no systematic or coordinated national dataset on status or condition of rangelands for the United States to make informed policy decisions (NRC 1994; Herrick et al. 2010). Rangelands in the west are sparsely populated, and assessments of rangeland conditions have historically not been uniformly conducted across all land ownership classes in any systematic monitoring program. Therefore, it is difficult to assess the current health of rangelands and which areas could benefit from targeted conservation as USDA Natural Resources Conservation Service (NRCS) has recently done for cropland within the Upper Mississippi River Basin (USDA NRCS 2010) and the Chesapeake
Bay (USDA NRCS 2011b) through the Conservation Effects Assessment Project (CEAP).
CEAP is a USDA initiative that is focused on quantifying environmental impacts of conservation on agricultural lands. The CEAP component aimed at assessing conservation on grazing lands was initiated in 2006 (Weltz et al. 2008). The challenges associated with assessments and monitoring on grazing lands and specifically rangelands are extreme due to the large spatial extent of the resource, mixed land ownership, high variability of biological attributes due to extremes in annual precipitation in arid and semiarid rangelands, no uniform sampling protocol, and no central agency assigned for conducting the assessment. The assessment of rangelands is further complicated by the difficulty in defining a baseline condition (reference condition) to document what changes have occurred. Additional challenges include developing cost-effective means of integrating quantitative data into an assessment protocol, high cost associated with collecting and processing national datasets, minimal analytical tools to interpret the results, and no dedicated team to develop and write the assessment."
by the federal government (USDA NRCS 2011a). The remaining rangelands are owned and managed by tribal, state, and local governments. Information on the type, extent, and spatial location of land degradation on rangelands is needed to inform policy and management decisions on rangelands; however, there is no systematic or coordinated national dataset on status or condition of rangelands for the United States to make informed policy decisions (NRC 1994; Herrick et al. 2010). Rangelands in the west are sparsely populated, and assessments of rangeland conditions have historically not been uniformly conducted across all land ownership classes in any systematic monitoring program. Therefore, it is difficult to assess the current health of rangelands and which areas could benefit from targeted conservation as USDA Natural Resources Conservation Service (NRCS) has recently done for cropland within the Upper Mississippi River Basin (USDA NRCS 2010) and the Chesapeake
Bay (USDA NRCS 2011b) through the Conservation Effects Assessment Project (CEAP).
CEAP is a USDA initiative that is focused on quantifying environmental impacts of conservation on agricultural lands. The CEAP component aimed at assessing conservation on grazing lands was initiated in 2006 (Weltz et al. 2008). The challenges associated with assessments and monitoring on grazing lands and specifically rangelands are extreme due to the large spatial extent of the resource, mixed land ownership, high variability of biological attributes due to extremes in annual precipitation in arid and semiarid rangelands, no uniform sampling protocol, and no central agency assigned for conducting the assessment. The assessment of rangelands is further complicated by the difficulty in defining a baseline condition (reference condition) to document what changes have occurred. Additional challenges include developing cost-effective means of integrating quantitative data into an assessment protocol, high cost associated with collecting and processing national datasets, minimal analytical tools to interpret the results, and no dedicated team to develop and write the assessment."
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... to hydrologic features), and soils (soil texture, depth, and percent rock outcrop; Table 3-3). Other layers specifically addressed in the habitat-modeling protocol were mountain ranges, temperature (mean annual minimum and maximum),... more
... to hydrologic features), and soils (soil texture, depth, and percent rock outcrop; Table 3-3). Other layers specifically addressed in the habitat-modeling protocol were mountain ranges, temperature (mean annual minimum and maximum), precipitation, and landform (Mannis et al. ...
The purpose of this data browser is to provide a spatial toolkit that delivers primary data that can be used for primary input information for assessments related to environmental endpoints, e.g. surface water hydrology and habitat... more
The purpose of this data browser is to provide a spatial toolkit that delivers primary data that can be used for primary input information for assessments related to environmental endpoints, e.g. surface water hydrology and habitat mapping, related to ecosystem services.
A necessary component in these landscape scale analyses is a contemporary land cover dataset and the ancillary spatial coverages which provide a baseline for subsequent habitat and hydrologic modeling, and conservation assessments. Thus, the content of this site can be used as the basis for landscape-scale assessments of ecological characteristics of aquatic ecosystems and impacts from land use and water quality management.
The extent of the datasets include all sub-watersheds of the South Platte River Basin (HUC 101900) that fall within the U.S. Environmental Protection Agency Region 8 states of Colorado and Wyoming and a portion of western Nebraska in Region 7.
The South Platte watershed contains many rapidly growing cities, each with increasing pressures on the natural environment and stressors on aquatic ecosystems due to land use change and water development. With projected population growth in excess of 50% by 2050, the need for data and best available science for environmental decision-making is critical to maintaining the integrity of the waters within the South Platte River Basin.
A necessary component in these landscape scale analyses is a contemporary land cover dataset and the ancillary spatial coverages which provide a baseline for subsequent habitat and hydrologic modeling, and conservation assessments. Thus, the content of this site can be used as the basis for landscape-scale assessments of ecological characteristics of aquatic ecosystems and impacts from land use and water quality management.
The extent of the datasets include all sub-watersheds of the South Platte River Basin (HUC 101900) that fall within the U.S. Environmental Protection Agency Region 8 states of Colorado and Wyoming and a portion of western Nebraska in Region 7.
The South Platte watershed contains many rapidly growing cities, each with increasing pressures on the natural environment and stressors on aquatic ecosystems due to land use change and water development. With projected population growth in excess of 50% by 2050, the need for data and best available science for environmental decision-making is critical to maintaining the integrity of the waters within the South Platte River Basin.
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Research Interests: Herpetology and Reptile
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Page 1. New Mexico Ecoregional Mapping and Modeling in the Southwest Regional Gap Analysis Project 15 April 2002 15 April 2003 PROGRESS REPORT New Mexico Cooperative Fish and Wildlife Research Unit Department ...