Prairie Dog Management Research Articles

DiazaCon reduces black-tailed prairie dog reproduction in Colorado

Context Black-tailed prairie dogs (Cynomus ludovicianus) often come into conflict with humans in urban natural areas adjacent to private property by destroying plants and denuding the landscape. There is a diversity of attitudes related to urban prairie dog management in Colorado and interest in non-lethal methods is increasing. Therefore, the development of non-lethal methods that allow the existence of prairie dogs and mitigate damage related to population density is needed. Aims The efficacy of DiazaCon (20,25-diazacholesterol dihydrochloride, a cholesterol analogue) as an oral contraceptive bait for reducing reproduction in black-tailed prairie dogs was tested. Persistence of DiazaCon in black-tailed prairie dogs 11 months after initial application was also determined. Methods Prairie dogs were baited with DiazaCon-coated rolled oats or control bait for 10 days over a 20-day period in November 2007 on one control and one treatment site. Sites were randomly assigned to a treatment group. Visual counts were used 8 months post-treatment (June/July 2008) to determine pup:adult ratios on both sites. Prairie dogs on both sites were trapped 11 months post-treatment (September/October 2008) to gather mass and age data to assess juvenile:adult ratios and to collect blood samples for determination of serum cholesterol and desmosterol concentrations. Key results DiazaCon treatment reduced the number of pups per adult by 95.5% when compared with the control site in June/July 2008 (0.09±0.02, n=10, number of observation days) versus 2.0±0.2 (n=10). Free serum cholesterol levels in treated animals (370.7µgmL–1) were lower than control animal levels (411.6µgmL–1, P<0.015), while treated desmosterol levels (14.5µgmL–1) were higher than controls (0.35µgmL–1, P<0.02) 11 months after ingestion of DiazaCon bait. However, these differences would likely not have been sufficient to prevent successful breeding in the upcoming breeding season. Conclusions DiazaCon is an effective contraceptive in black-tailed prairie dogs. It is probably reversible and will likely affect breeding success for only one breeding season. DiazaCon may provide an additional tool to help manage urban populations of prairie dogs in locations where lethal control is unacceptable. Implications The need for further research into secondary hazards to non-target animals, such as predators, is discussed. Recommendations for field application are also discussed.

Use of Ecological Sites in Managing Wildlife and Livestock: An Example with Prairie Dogs

On the Ground The perception of prairie dogs among Native Americans living on the Standing Rock Sioux Reservation is mixed. Some Native Americans focus on the loss of forage productivity, whereas others are interested in the cultural and ecological aspects of prairie dogs. The use of ecological sites may provide a mechanism for developing a management framework that would consider both livestock and prairie dogs. The three ecological sites we surveyed had large differences in off-colony standing crop, but in 2 of the 3 years we surveyed, there were no differences between standing crop on-colony. This suggests that management of prairie dogs on rangelands should focus on limiting prairie dogs on more productive ecological sites with less productive sites receiving less emphasis.

Resilience of a novel ecosystem after the loss of a keystone species: plague epizootics and urban prairie dog management

In a complex urban‐impacted landscape, native black‐tailed prairie dogs (Cynomys ludovicianus) amplify the trajectory at which grassland plant communities deviate from historical configurations. Prairie dog removal has been proposed as an intervention method based upon the premise that removing a major directional driver of change will initiate the recovery of historically common plant communities. However, in a heavily anthropogenically influenced landscape with a matrix containing only small fragmented areas of native vegetation, the recolonization speed and success of native plant species may not match those observed in less anthropogenically influenced landscapes. This study examined the effect of urban prairie dog removal by using remote sensing to observe the response of plant communities near Boulder, Colorado, USA to plague epizootics. We used Mann‐Whitney U tests to compare the soil adjusted vegetation index (SAVI) values from colonies recently extirpated by plague to both areas unoccupied by prairie dogs and to plague‐absent colonies. Analysis of 67 Landsat images in three growing season subsets suggested that prairie dog removal alone does not return colony plant communities to compositions representative of grassland areas unoccupied by prairie dogs. The absence of SAVI value changes in the mid‐ and late‐growing seasons suggested that novel vegetation communities on urban prairie dog colonies were highly resilient systems, and prairie dog removal alone was insufficient for restoration. Furthermore, increased early season SAVI values on extirpated colonies could indicate a proliferation of introduced winter active species and exotic forbs, not the desired reemergence of native species, but rather species expected given current climatic changes. Intensive management efforts appear necessary for overcoming the thresholds required to restore urban prairie dog colonies to their historical compositions, an effort made increasingly more difficult with the ongoing effects of other global change drivers.

Food limitation at species range limits: Impacts of food availability on the density and colony expansion of prairie dog populations at their northern periphery

Understanding limiting factors affecting population growth for imperilled species is crucial for conservation and management. This research investigates whether black–tailed prairie dog (Cynomys ludovicianus) populations are food limited on their northernmost range extent. We measured background vegetation rates and used food supplementation in a ‘before–after–control–impact’ (BACI) design to test whether increased food positively impacted prairie dog population density and colony expansion. Experimental results did not support food limitation. Overall, density increased from 2008 to 2009 but remained relatively similar between control and treatment plots. Correlations between natural, non-supplemented vegetation biomass and prairie dog density suggest that natural food availability in 2008 may have driven population growth into 2009. Natural food availability was highly variable among years and prairie dog densities may be impacted by food scarcity in some years but not others. Colony spatial expansion was greater in the absence of food supplementation, suggesting food scarcity may drive colony expansion. This research has important implications for the conservation and management of prairie dogs and species that depend on them such as reintroduced black–footed ferrets (Mustela nigripes) in Canada and other populations across their range.

Effect of GonaCon™ vaccine on black-tailed prairie dogs: Immune response and health effects

Management of prairie dogs in the past has included poisoning, fumigants, barriers, and relocation. Because of the diverse attitudes related to prairie dog management, nonlethal methods that allow the existence of prairie dogs but help minimize damage related to population growth need to be developed. GonaCon™ is an immunocontraceptive vaccine that elicits antibodies to native GnRH; this prevents the secretion of reproductive hormones necessary for sperm and oocyte production. Prairie dogs were vaccinated with 0.1, 0.2, or 0.4mL of the GonaCon™ emulsion intramuscularly in the upper thigh containing 100, 200, or 400μg GnRH conjugate, respectively. Control animals were vaccinated with 0.4mL saline emulsion in the upper thigh. Blood samples (≤1mL) were taken from the femoral vein once pretreatment and at 1, 2, 3, 4, 6, and 15 months post-vaccination. Age (adult or juvenile) did not affect immune response to GonaCon™. Antibody titers were higher in the 200 and 400μL GonaCon™ groups than in the 100μL group, and there was no difference between the 200 and 400μL GonaCon™ groups. No adverse effects of GonaCon™ were noted on weight or blood chemistry parameters during the study. GonaCon™ will likely contracept prairie dogs for ≥1 year in the field using either 200 or 400μg conjugate. GonaCon™ could be incorporated into management plans to help maintain prairie dog populations while reducing habitat degradation due to overpopulation.

Perceptions of wildlife damage and species conservation: lessons learned from the Utah prairie dog

The Utah prairie dog (Cynomys parvidens), a federally listed threatened species, causes damage to agricultural operations, yet little incentive exists for private landowners to conserve them. Therefore, we surveyed Utah residents to identify stakeholder attitudes regarding prairie dog management. We assessed how perceptions of wildlife damage affect respondent attitudes regarding conservation among agricultural producers, rural residents, and urban residents. Higher levels of perceived wildlife damage were reported for agriculture respondents (79%) than for urban (20%) or rural (45%) respondents. Compensation for damage caused by Utah prairie dogs was supported by those engaged in agricultural production but not by rural or urban respondents. Agricultural producers, rural residents and urban residents all stated a preference for private conservation organizations to fund damage compensation rather than a government agency. Most agricultural respondents (61%) and rural respondents (64%) believed that Utah prairie dogs should be only on public lands. Some agricultural respondents (23%) thought they should be on no land. Attitudes regarding the Utah prairie dog varied, with agricultural producers being the most negative and urban respondents the most positive. The negative attitude of rural residents and agricultural producers probably results from both the damage caused by Utah prairie dogs and land-use restrictions resulting from the species being listed as threatened. Acceptance of Utah prairie dogs by private landowners may be key to the recovery of the species, and our fi ndings suggest that alleviation of damage issues may increase landowner acceptance of conservation measures to protect Utah prairie dogs.

A comparison of metrics predicting landscape connectivity for a highly interactive species along an urban gradient in Colorado, USA

Many organisms persist in fragmented habitat where movement between patches is essential for long-term demographic and genetic stability. In the absence of direct observation of movement, connectivity or isolation metrics are useful to characterize potential patch-level connectivity. However, multiple metrics exist at varying levels of complexity, and empirical data on species distribution are rarely used to compare performance of metrics. We compared 12 connectivity metrics of varying degrees of complexity to determine which metric best predicts the distribution of prairie dog colonies along an urban gradient of 385 isolated habitat patches in Denver, Colorado, USA. We found that a modified version of the incidence function model including area-weighting of patches and a cost-weighted distance surface best predicted occupancy, where we assumed roads were fairly impermeable to movement, and low-lying drainages provided dispersal corridors. We also found this result to be robust to a range of cost weight parameters. Our results suggest that metrics should incorporate both patch area and the composition of the surrounding matrix. These results provide guidance for improved landscape habitat modeling in fragmented landscapes and can help identify target habitat for conservation and management of prairie dogs in urban systems.

Landscape ecology as a foundation for sustainable conservation

Landscape ecology and conservation share a common focus on places, but they differ in their perspectives about what is important about those places, and the integration of landscape ecology into conservation is far from complete. I consider four ways in which landscape ecology can contribute to conservation. First, protected areas that are established for conservation are not stand-alone isolates. They exist in the context of broader landscape mosaics, which may encourage or discourage movements of individuals into and out of an area. Second, the landscape surroundings of a preserve may contain threats to the biodiversity within the preserve, many of them consequences of human activities. In combination, these relationships with the surroundings may make the “effective area” of a preserve different from that shown on a map. Third, the scale of an administrative area or of management action may not coincide with the scales of populations, disturbances, or ecological processes, creating challenges to both landscape ecology and conservation. Finally, landscapes encompass people and their activities; sustainability of conservation requires consideration of the tradeoffs between human uses and the biodiversity values of a landscape. I illustrate these four themes with a case study of the management of prairie dogs (Cynomys ludovicianus) in the Great Plains of North America, where the tensions between conservation and human land uses are particularly high. Ecologists and conservationists consider prairie dogs as keystone species in these grassland ecosystems and primary targets for conservation, but many private landowners regard them as varmints that consume valuable livestock forage and degrade rangeland condition. Effective conservation of functioning grasslands must include prairie dogs, and this in turn requires that the issues be addressed in terms of the biological, social, and cultural features of entire landscapes. Important as they are, areas protected for conservation cannot by themselves stem the tide of global biodiversity loss. The perspective must be broadened to include the landscapes where people live and work, recognizing the dynamic nature of landscapes and the factors driving land-use change. Landscape ecologists must work together to overcome the cultural differences between their disciplines, and between academic science and conservation practice and management. It can, and must, be done.

Prairie Dog Contraception (Abstract only)

Traditional methods of prairie dog management are not always practical or acceptable. Therefore, other methods need to be developed to aid managers responsible for prairie dog management. Contraception is one such method being developed at the National Wildlife Research Center (NWRC). GonaCon™, an immunocontraceptive vaccine, has shown promise for other species when administered as a single shot. A laboratory dose-response study and a field study using GonaCon™ with black-tailed prairie dogs are being conducted concurrently at NWRC. DiazaCon™ is an oral contraceptive that resulted in a 47% reduction in the number of pups/adult in a preliminary field trial. However, treatment was administered late in the breeding season in that trial. A new field study is currently underway to examine the effects of DiazaCon™ on reproduction when administered to black-tailed prairie dogs just prior to the breeding season.

Conservation of the Black-Tailed Prairie Dog: Saving North America's Western Grasslands, by Hoogland, J. L. (ed.)

J. L. Hoogland (ed.). 2006. Conservation of the Black-Tailed Prairie Dog: Saving North America's Western Grasslands.Island Press, Washington, D.C., 350350 pp. ISBN 1-55963-498-7, price (paper), $35. Conservation of the Black-Tailed Prairie Dog is a collection of papers written by many authors—including editor John L. Hoogland, who has devoted most of his professional career to the study of prairie dog biology—that aims to provide a summary of all current data concerning 1 of North America's keystone species, the black-tailed prairie dog ( Cynomys ludovicianus ), and the conservation of this species. With 30 contributing authors, this work provides substantial information on C. ludovicianus and also includes a very broad range of discussion stemming from different specializations. Incorporated into the text are many photographs and illustrations that help to support the writing. The main theme, of course, is conservation. Separated into 3 parts, this book serves to inform and offer solutions for the preservation and management of prairie dogs. Part I of the book is an overview of the natural history of prairie dogs, including demography and population dynamics, social structures, and discussion of C. ludovicianus as a keystone species. Hoogland points out that without solid and long-term scientific knowledge of prairie dog biology, we cannot act …

High prevalence of Yersinia pestis in black-tailed prairie dog colonies during an apparent enzootic phase of sylvatic plague

Sylvatic plague (Yersinia pestis) was introduced into North America over 100 years ago. The disease causes high mortality and extirpations in black-tailed prairie dogs (Cynomys ludovicianus), which is of conservation concern because prairie dogs provide habitat for the critically endangered black-footed ferret (Mustela nigripes). Our goal was to help elucidate the mechanism Y. pestis uses to persist in prairie ecosystems during enzootic and epizootic phases. We used a nested PCR protocol to assay for plague genomes in fleas collected from prairie dog burrows potentially exposed to plague in 1999 and 2000. No active plague epizootic was apparent in the 55 prairie dog colonies sampled in 2002 and 2003. However, 63% of the colonies contained plague-positive burrows in 2002, and 57% contained plague-positive burrows in 2003. Within plague-positive colonies, 23% of sampled burrows contained plague-positive fleas in 2002, and 26% contained plague-positive fleas in 2003. Of 15 intensively sampled colonies, there was no relationship between change in colony area and percentage of plague-positive burrows over the two years of the study. Some seasonality in plague prevalence was apparent because the highest percentages of plague-positive colonies were recorded in May and June. The surprisingly high prevalence of plague on study area colonies without any obvious epizootic suggested that the pathogen existed in an enzootic state in black-tailed prairie dogs. These findings have important implications for the management of prairie dogs and other species that are purported to be enzootic reservoir species.

BEHAVIORAL RESPONSES TO REPEATED HUMAN INTRUSION BY BLACK-TAILED PRAIRIE DOGS (CYNOMYS LUDOVICIANUS)

This study addressed behavioral responses by black-tailed prairie dogs (Cynomys ludovicianus) to human intrusion in urban and rural environments in Boulder, Colorado. We expected that if prairie dogs habituate to repeated disturbances, they should allow a recurring human intruder to approach closer over time before sounding an alarm bark or initiating concealment. We also predicted that urban colonies could be approached more closely than rural colonies before displaying an avoidance response. Four colonies (2 rural and 2 urban) were approached >100 times over a 7-month period. Rather than exhibiting habituation, prairie dogs demonstrated increased responsiveness in concealment behavior, retreating to their burrows earlier, with recurring disturbances. Barking distances did not change consistently with repeated intrusion, but, over time, prairie dogs barked less frequently when performing their avoidance response, a result with implications for prairie dog management. Rural colonies had higher initial concealment distances, and these distances increased more rapidly with repeated intrusion than did concealment distances in urban colonies. Thus, rural prairie dogs may be more sensitive to human intrusion than urban prairie dogs.

Public Knowledge and Perceptions of Black-Tailed Prairie Dogs

Black-tailed prairie dogs (Cynomys ludovicianus) historically occupied an 11-state region of the United States. We surveyed 1,900 residents (response rate 56%) of this region to understand citizen knowledge and perceptions about prairie dogs and their management. Those who have direct experience--e.g., those who live very close to prairie dog colonies or know the location of the nearest colony--have higher levels of knowledge. A significantly higher level of knowledge was documented among those who were politically active when compared with the general public. Those who found environmental issues difficult to understand were associated with lower knowledge. People with direct experience were likely to hold negative views, whereas those holding environmentalist values were likely to express positive attitudes toward the species. Although those with higher education reported more knowledge, there was no link between a person's level of knowledge and perceptions of prairie dog management.

Urban-suburban prairie dog management: opportunities and challenges

Author(s): Witmer, Gary W.; VerCauteren, Kurt C.; Manci, Karen M.; Dees, Donna M. | Abstract: The historic range of the black-tailed prairie dog has undergone dramatic declines in the last century, prompting concern about the species’ long-term viability. While considered a pest by many, others believe that the species is a keystone element of prairie ecosystems. Urban-suburban land managers are challenged with preserving colonies of prairie dogs on public lands while dealing with many conflicting interests, social costs, and risks. We review the management plans that municipalities have designed to reduce conflicts by using public input, zoned management, and a variety of management techniques. Areas of difficulty and research needs are also discussed.

Prairie dog poisoning in northern Great Plains: An analysis of programs and policies

This paper describes the programs and policies regarding prairie dog control in the northern Great Plains states of Montana, South Dakota, and Wyoming. The poisoning programs of federal and state agencies are described, along with the statutes and legal mandates that shape agency management of prairie dogs. Current policies on National Grasslands and other federal lands typically limit prairie dogs to small percentages of available potential habitat, to the detriment of prairie dogs and associated species. State programs to assist landowners in prairie dog control differ greatly, employing cost-share incentives (Wyoming) and regulatory fines (South Dakota) to encourage the poisoning of prairie dogs. Prairie dog control is not actively funded or practiced by state or county agencies in Montana. We document federal and state involvement in more than 1 million acres of prairie dog poisoning in the study area during 1978-1992. In combination with undocumented poisoning by private landowners, plague, and shooting, prairie dogs may be experiencing net regional declines, contributing to the disintegration of the prairie dog ecosystem. We recommend that Animal Damage Control operations concerning prairie dogs be terminated, on the basis that they duplicate state programs and are at cross purposes with federal wildlife management programs that seek to perpetuate and/or recover wildlife species that depend on the prairie dog ecosystem. We further recommend that federal range improvement funds be offered as subsidies for the integration of prairie dogs in range management, as opposed to funding prairie dog eradication programs.

Biodeterioration of the biosphere: Where does wildlife damage management stand?

Degradation of the biosphere with the associated loss of biological integrity is the most critical issue facing humankind today. Wildlife damage management expertise is critically needed in addressing this issue head-on from both traditional and non-traditional approaches. The profession offers a unique combination of both wildlife management training and damage management experience, which helps in understanding a variety of conservation perspectives, especially on private land. Because relationships between damage management and sustainability are often not clearly recognized, and because many traditional wildlife damage management activities are criticized as inappropriate or not needed, we suggest a reassessment of our vision for the future of the profession to include biosphere sustainability as a basic guiding principle. Implications could include greater emphasis in some areas and reassessment in others such as prairie dog management. Greater emphasis might be placed on native ecosystems, impacts of invasive exotic species or overabundant native species, fragmented habitats, nest pests, and, particularly, sustainable agricultural issues. A shift toward greater service to biosphere sustainability will bring both rewards and responsibilities. It will also strengthen the relevance of wildlife damage management and enhance the credibility of the profession for the future.

A GIS approach to modifying stocking rates on rangelands affected by prairie dogs

Abstract The Bureau of Indian Affairs is responsible for the management of trust resources on Indian lands. A portion of this responsibility is the management of prairie dogs on the Fort Belknap Reservation in north central Montana. Geographic Information Systems (GIS) and Remote Sensing technologies were incorporated into a 5 year management program. GIS technology was used to determine a method to modify animal unit month (AUM) stocking rates on rangeland affected by prairie dogs. Baseline prairie dog town mapping was completed in 1990 using satellite imagery at a scale of 1: 24000. GIS analysis using the SPOT* data, range site index information, and administrative boundaries was performed to determine AUMs contained within prairie dog towns. Subsequent analysis will ascertain the response to specific management efforts in relation to prairie dog population levels throughout the life of the project.

Aerial Prebaiting for Management of Prairie Dogs with Zinc Phosphide

Aerial Prebaiting for Management of Prairie Dogs with Zinc Phosphide

The use of Diethystilbestrol as a Temporary Chemosterilant in Black-Tailed Prarie Dogs (Cynomys ludovicianus)

The following is an abstract of a manuscript submitted to the Journal of Range Management - 25 September 1982. Abstract. The effectiveness of diethylstilbestrol (DES), a synthetic estrogen, as a reproductive inhibitor in black-tailed prairie dogs (Cynomys ludovicianus) was examined in a 4-year study at Wind Cave National Park, South Dakota. In 1979 and 1980, a study colony was monitored to determine age structure, reproductive success of individual animals, and rate of colony expansion. In 1981, the colony was divided into control and experimental areas (Fig. 1). Treatment with DES during the breeding season resulted in complete curtailment of reproduction on the experimental side while reproduction of the control group was similar to that of previous years. Results were identical in 1982 when treatment was reversed (Fig. 2). There were no obvious effects of DES treatment on the subsequent reproductive capability of study animals. In 1981, surface expansion of the study colony was significantly less on the DES-treated side compared with previous years (Fig. 3). Prospects of using DES for managing prairie dog populations are discussed. The authors visualize an integrated approach to prairie dog management; that is, use of rodenticide for initial reduction and irregular DES treatments thereafter to maintain the population at low levels.

Application of Remote Sensing to Prairie Dog Management

Application of Remote Sensing to Prairie Dog Management