Our team developed a large-scale collaborative conservation planning initiative for the black-tailed prairie dog (BTPD) ecosystem that stretches across North America’s central grasslands. Because prairie dogs are keystone species, their conservation and management often lie at the core of grassland conservation efforts. Through spatial modelling, we identified potential landscapes for prairie dog ecosystem conservation that consider ecological, political and social factors, along with changing climate and land use to maximize long-term conservation potential and co-existence with human activities.
Results and data include:
- a habitat suitability model under current and projected future climates
- priority landscapes for ecosystem conservation across BTPD's range within the U.S.
FIGURE 1. The ecological role of prairie dogs cascades throughout the prairie dog ecosystem. Plus (+) signs equal an increase in an ecosystem property as a result prairie dogs; minus (-) signs indicate a decrease. (Drawings by Sharyn Davidson; modified version from Davidson et al. 2012 Frontiers in Ecol & Environ)
Methods & Results
The Habitat Sustainability Model (HSM) is based on presence and absence data for occurrences across the geographic range of the BTPD within the U.S. and how the occurrences relate to climate, soils, topography and land cover. The BTPD HSM is projected under two future climate scenarios: warm/wet and hot/dry.
Large areas of suitable habitat is available for the BTPD ecosystem, across their U.S. range and within each state. 20.8 million hectares of remaining suitable grassland habitat were identified. However, only 1.9 million hectares (9%) are currently occupied by BTPDs. Results demonstrate the large amount of conservation potential for the prairie dog ecosystem. Such findings are encouraging for associated species that depend on BTPDs and their colonies for habitat, and for those species that require large colonies to support their populations.
The HSM can help inform conservation planning and efforts to promote coexistence. For example, the impacts BTPDs can have on livestock producers and the susceptibility of BTPD populations to plague will continue to be major factors affecting conservation efforts. Mitigating impacts on livestock producers requires careful consideration of the spatial distribution of colonies on and adjacent to livestock operations, and how management can effectively maintain colony complexes in desired locations while preventing expansion into undesired areas. The HSM can assist in planning efforts not only by ensuring that locations targeted for BTPD conservation are in optimal habitat, but also in identifying transition zones between high and low habitat suitability where expansion may be more effectively and naturally prevented, to reduce the need for lethal control. Maps can be used to assess whether landscapes targeted for conservation efforts are large enough to support conservation goals for associated species such as black-footed ferrets and mountain plovers, which rely on extensive colony complexes. Additionally, the maps can support analyses of potential connectivity among colonies across landscapes, which often affects the likelihood and scale of plague epizootics. Another utility is informing which landowners might participate in payment programs for black-footed ferret recovery, by showing how their lands relate to the broader landscape and may help to achieve range-wide conservation goals.
FIGURE 2. Methodological approach for developing the BTPD habitat suitability model.
FIGURE 3. Spatial layers created for the BTPD HSM, based on occurrence (McDonald et al., 2015), climate (Abatzoglou, 2013), land cover (USGS, 2019), topography (USGS, 2018) and soils (Chaney et al., 2019a, b).
FIGURE 4. BTPD ensemble habitat suitability model, under current climate. Dark green shows areas of highest habitat suitability for BTPDs and beige shows areas of lowest suitability.
FIGURE 5. BTPD ensemble HSM projected under future climate scenarios. Dark green shows areas of highest habitat suitability for BTPDs and beige shows areas of lowest suitability.
| State | Area of low habitat suitability (ha) | Area of medium habitat suitability (ha) | Area of high habitat suitability (ha) | Area of medium + high habitat suitability (ha) | Area of medium + high habitat suitability occupied by BTPDs (ha) | Percent of medium + high habitat suitability occupied by BTPDs (%) |
|---|---|---|---|---|---|---|
| Arizona | 13,750 | 5,789 | 108 | 5,897 | 34 | 0.58% |
| Colorado | 1,338,636 | 1,558,562 | 4,216,600 | 5,775,162 | 532,251 | 9.22% |
| Kansas | 631,120 | 420,207 | 760,199 | 1,180,406 | 154,775 | 13.11% |
| Montana | 1,763,366 | 1,345,433 | 1,588,702 | 2,934,135 | 184,055 | 6.27% |
| Nebraska | 692,534 | 441,174 | 389,552 | 830,726 | 89,208 | 10.74% |
| New Mexico | 1,169,982 | 863,150 | 728,047 | 1,591,197 | 124,098 | 7.80% |
| North Dakota | 340,733 | 180,275 | 63,826 | 244,101 | 15,561 | 6.37% |
| Oklahoma | 280,290 | 212,791 | 480,503 | 693,294 | 81,224 | 11.72% |
| South Dakota | 1,711,314 | 1,277,664 | 1,470,485 | 2,748,149 | 224,145 | 8.16% |
| Texas | 1,018,266 | 804,629 | 1,064,014 | 1,868,643 | 238,871 | 12.78% |
| Wyoming | 1,064,272 | 1,021,180 | 1,961,438 | 2,982,618 | 288,606 | 9.68% |
| Entire US Range | 10,024,502 | 8,130,936 | 12,723,491 | 20,854,427 | 1,932,826 | 9.27% |
Methods
We used a conservation planning analysis to identify potential landscapes for conservation across North America’s central grasslands, with a focus on the BTPD ecosystem within the U.S. The goals of this analysis were to assess the suitability of the habitat for the prairie dog ecosystem and how the social and political landscape, threats to prairie dog habitat (e.g., development), habitat connectivity and general ecological landscape (e.g., percent cover of grass) collectively influence opportunities to conserve the BTPD ecosystem. Potential landscapes were selected for prairie dog ecosystem conservation using the spatial conservation prioritization method and Zonation software.
FIGURE 6. Methodological approach for identifying suitable landscapes for the black-tailed prairie dog (BTPD) ecosystem conservation.
Results
Extensive areas of HCP habitat for BTPD ecosystem conservation were identified, especially across the western portion of the geographical range. These HCP areas represent 6% (top 10%) and 22% (top 30%) of their historical distribution within the U.S. and remain strongholds under projected climate change.
Of the suitable habitat, 96,944 km2 have the greatest conservation potential (the top 10%) when also considering the threat, social and political landscapes, future climate and habitat connectivity. Much of the HCP habitat is located across regions where extensive, intact grassland habitat remains. These areas were also located where climate, soils and topography were most suitable for BTPDs.
FIGURE 8. Conservation potential across BTPD geographical range under current and future climate scenarios, considering all spatial variables. (a) Conservation potential under the current climate; (b) conservation potential under the warm and wet (W&W) future climate scenario; (c) conservation potential under the hot and dry future climate scenario; (d) overlap of the top 10% of lands with high conservation potential across the present and future climate scenarios; (e) overlap of the top 30% of lands with high conservation potential across the present and future climate scenarios. The priority rankings in panels a, b and c are as follows: 2% (from 0.98 to 1 of priority rank) Light red; 5% (from 0.95 to 0.979 of priority rank) Dark red; 10% (from 0.90 to 0.949 of priority rank) Pink; 30% (from 0.70 to 0.89 of priority rank) Yellow; 50% (from 0.50 to 0.79 of priority rank) Light blue; 75% (from 0.25 to 0.499 of priority rank) Dark blue; 100% (from 0.00 to 0.249 of priority rank) Black.
FIGURE 7. Conservation potential across the BTPD geographical range within the U.S. considering only habitat suitability and current climate. Priority rankings are as follows: 2% (from 0.98 to 1 of priority rank) Light red; 5% (from 0.95 to 0.979 of priority rank) Dark red; 10% (from 0.90 to 0.949 of priority rank) Pink; 30% (from 0.70 to 0.89 of priority rank) Yellow; 50% (from 0.50 to 0.79 of priority rank) Light blue; 75% (from 0.25 to 0.499 of priority rank) Dark blue; 100% (from 0.00 to 0.249 of priority rank) Black.
Because conservation policies and funding decisions are often made by political entities, we identified STATE-LEVEL conservation priorities, under both present and projected future climate. Our analysis sought conservation solutions within each of the states’ boundaries, so do not consider a rangewide perspective.
STATE-LEVEL conservation priorities differed considerably from RANGEWIDE priorities, under both current and future climate scenarios. The largest difference was among the southern states (AZ, NM, and TX), where climate change reduces the conservation priorities across this region more when viewed from a RANGEWIDE perspective than when viewed from a STATE-LEVEL perspective. Additionally, from a RANGEWIDE perspective, eastern states have fewer areas with HCP compared to western states within the BTPD range, but when viewed from a STATE-LEVEL perspective there are considerably more areas with HCP. Differences were expected because this question was aimed at understanding the HCP areas within each state, so the analysis sought conservation solutions within each states’ boundaries. Identifying STATE-LEVEL conservation priorities is important because funding sources and management priorities are often focused at the state-level and not range-wide. This way, each state has information on conservation priorities within their own jurisdictional boundaries. Each state may wish to focus conservation efforts for the BTPD ecosystem in those areas that remain priorities into the future at the STATE-LEVEL, while also considering those priorities identified within their state under the RANGEWIDE perspective.
| State | Area (km2) | Percent (%) |
|---|---|---|
| Colorado | 24,084 | 24.8 |
| Montana | 19,401 | 20.0 |
| South Dakota | 19,331 | 19.9 |
| Wyoming | 18,947 | 19.5 |
| New Mexico | 7,082 | 7.3 |
| Nebraska | 2,525 | 2.6 |
| Arizona | 1,845 | 1.9 |
| Texas | 1,552 | 1.6 |
| Oklahoma | 1,059 | 1.1 |
| North Dakota | 699 | 0.7 |
| Kansas | 420 | 0.4 |
| Total | 96,944 | 100 |
FIGURE 9. State-level conservation potential across BTPD geographical range under current and future climate scenarios, considering all spatial variables. (a) Conservation potential under the current climate; (b) conservation priorities under the warm and wet (W&W) future climate scenario; (c) conservation potential under the hot and dry (H&D) future climate scenario; (d) overlap of the top 10% of lands with high conservation potential across the present and future climate scenarios; (e) overlap of the top 30% of lands with high conservation potential across the present and future climate scenarios. The priority rankings in panels a, b and c are as follows: 2% (from 0.98 to 1 of priority rank) Light red; 5% (from 0.95 to 0.979 of priority rank) Dark red; 10% (from 0.90 to 0.949 of priority rank) Pink; 30% (from 0.70 to 0.89 of priority rank) Yellow; 50% (from 0.50 to 0.79 of priority rank) Light blue; 75% (from 0.25 to 0.499 of priority rank) Dark blue; 100% (from 0.00 to 0.249 of priority rank) Black.
Conclusions
Findings highlight the conservation potential for BTPDs and associated species and the maps can be incorporated into other large-scale, multi-species conservation planning efforts being developed for the Central Grasslands of North America.
Landscapes with the HCP for the BTPD ecosystem were largely distributed across the western portion of the current/historical range. BTPD conservation might be best maximized by focusing on areas that have HCP under both current and projected future climate. HCP areas in the southern part of the range, such as northeastern NM, may remain priorities well into the future and be worthy of conservation investments.
Most (65%) of the top 10% of land with HCP, across all three climate scenarios, were located on private land, compared to public land (24%). However, across the western distribution of the range, there remains considerable public land, especially federal and state land, and Indigenous land (8%) that may provide valuable opportunities for conservation of the BTPD ecosystem. Yet, the extent to which private, public and Indigenous lands will support BTPD ecosystem conservation, is strongly influenced by the social and political landscapes within which they are embedded. While the prairie dog ecosystem faces numerous threats from plague and habitat loss, the social landscape is often considered the greatest and most challenging barrier to successful conservation of the BTPD ecosystem.
The HCP areas encompass or overlap with many of the regions also identified in other landscape-level conservation priority analysis for the Central Grasslands (Comer et al. 2018; Pool and Panjabi 2011), but this project also illuminates extensive, additional regions of grassland priority.
| Landownership | Area (km2) | Percent (%) |
|---|---|---|
| Private | 63,447 | 65.4 |
| Federal | 14,021 | 14.5 |
| State | 9,347 | 9.6 |
| Indigenous lands | 7,779 | 8.0 |
| NGO/private conservation | 2,250 | 2.3 |
| Local/Regional | 100 | 0.1 |
| Total | 96,944 | 100 |
FIGURE 10. Maps of (a) the intersection of the top 10% and 30% of areas with HCP for BTPD ecosystem (across the three climate scenarios), (b) those same top 10% of areas with high conservation potential intersected with different landownership types (data are from PAD-US (USGS 2019b) and NCED and other Private Land Conservation areas, Table 1; see also Table 3) and (c) the top 10% and 30% of areas with high conservation potential (as in panel a) overlapped with grassland priority areas (GPAs) for the Central Grasslands identified by Pool and Panjabi (2011) and by Comer et al. (2018).
Ana Davidson, Colorado Natural Heritage Program & Dept. of Fish, Wildlife and Conservation Biology, Colorado State University
Bill Van Pelt, Western Association of Fish & Wildlife Agencies
David Augustine, USDA-Agricultural Research Service
Fernanda Thiesen Brum, Universidade Federal do Paraná - Brazil
Lindsey Sterling-Krank, Prairie Dog Coalition, Humane Society of the U.S.
Matt Williamson, Boise State University
Michael Houts, Kansas Biological Survey & Center for Ecological Research, University of Kansas
Michael Menefee, Colorado Natural Heritage Program, Colorado State University
Michelle Fink, Colorado Natural Heritage Program, Colorado State University
