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Accurate estimates of population dynamics play a major role in formulating conservation strategies for Gunnison's prairie dogs (Cynomys gunnisoni) and other keystone species. Over 5 years (2014–2018) at Valles Caldera National Preserve in NM, USA, we used a portable ultrasound machine (PUM) to investigate the presence or absence of pregnancy, and to determine uterine litter size for 238 pregnant female Gunnison's prairie dogs from two colonies. We compared litter size at weaning for 168 of these 238 females and we found no significant difference between uterine litter size and litter size at weaning. For 76 of these 168 females (45%), estimates of uterine litter size and litter size at weaning were identical. We detected no significant variation among years for uterine litter size versus litter size at weaning. To our knowledge, our research is the first to compare uterine litter size to litter size at weaning for the same group of females living under natural conditions. [ABSTRACT FROM AUTHOR]

Gunnison's prairie dogs, Cynomys gunnisoni , frequently utter a repetitive series (a 'bout') of alarm calls (called 'barks') in response to a variety of terrestrial predators. Previous work has suggested that the structure of barks is finely tuned in ways that provide highly specific information about the identity of the predator. We re-evaluated these findings by presenting individually marked adult females with taxidermy mounts of three terrestrial predators of prairie dogs: a coyote, Canis latrans , a bobcat, Lynx rufus , and an American badger, Taxidea taxus , as well as one control stimulus (a cardboard box). Significant variation among individuals was evident from analyses of 10 measures associated with the general pattern of barking (e.g. latency to begin barking, bout duration, average number of barks/bout, overall bark rate, interbout interval) and also from eight structural features of individual barks (e.g. frequency and duration measures of the fundamental frequency band). When controlling for the identity of alarm callers, we found little evidence for differences in these same variables in response to different stimuli. We conclude that, like several other species of ground-dwelling squirrels, Gunnison's prairie dogs have an individually distinctive alarm call that does not differ for different predators. Our results conflict with earlier claims of extreme specificity in the alarm calls of Gunnison's prairie dogs. Highlights • We tested whether Gunnison's prairie dog alarm calls show referential specificity. • Controlling for caller ID, we found little evidence of call variation to four stimuli. • However, individuals' alarm calls were distinct from one other. • Previous studies not considering individual variation need to be re-evaluated. [ABSTRACT FROM AUTHOR]

Summary: Plague is a zoonotic disease (transmitted mainly by fleas and maintained in nature by rodents) that causes severe acute illness in humans. We present a human plague case who became infected by the bite of a wild Gunnison's prairie dog, and a good practical example of the One Health approach that resulted in a rapid public health response. The exposure occurred while the animal was being transported for relocation to a wildlife refuge after being trapped in a plague enzootic area. This is the first report of a human plague case resulting from the bite of a Gunnison's prairie dog. Additionally, we present an observation of a longer incubation period for plague in captive prairie dogs, leading to a recommendation for a longer quarantine period for prairie dogs during translocation efforts. [ABSTRACT FROM AUTHOR]

Abstract Gunnison's prairie dog (Cynomys gunnisoni) is an herbivore that ranges from desert grasslands to high‐montane meadows and is limited by disease across much of its range. The importance of abiotic drivers to the population dynamics of the species is poorly known. We employed stable isotope analysis to investigate energy assimilation patterns as indicators of abiotic limitation in arid grassland and montane populations of C. gunnisoni during a multi‐year drought. Standard ellipse areas of plasma and red blood cell carbon (δ13C) and nitrogen (δ15N) isotope values, representing population‐level foraging niche widths, declined during years and seasons of drought stress at both study sites. Prairie dogs at the montane site, but not at the desert grassland site, maintained seasonal shifts in dietary niche width corresponding to periods of favorable growth conditions for the more nutritious C3 plants. Production of offspring was strongly and positively correlated with C3 resource use as indicated by δ13C values in metabolically active tissues (plasma and red blood cells), but not with δ13C values in adipose tissues used for long‐term energy storage, or with foraging niche widths. These findings demonstrate that assimilation of energy from C3 plants is associated with increased reproductive output and that drought conditions importantly constrain the resource base available to C. gunnisoni. The link between plant nutritional quality and demographic parameters highlights the role of abiotic regulation within this reportedly disease‐limited species.

Gunnison's prairie dog ( Cynomys gunnisoni) is an herbivore that ranges from desert grasslands to high-montane meadows and is limited by disease across much of its range. The importance of abiotic drivers to the population dynamics of the species is poorly known. We employed stable isotope analysis to investigate energy assimilation patterns as indicators of abiotic limitation in arid grassland and montane populations of C. gunnisoni during a multi-year drought. Standard ellipse areas of plasma and red blood cell carbon (δ13C) and nitrogen (δ15N) isotope values, representing population-level foraging niche widths, declined during years and seasons of drought stress at both study sites. Prairie dogs at the montane site, but not at the desert grassland site, maintained seasonal shifts in dietary niche width corresponding to periods of favorable growth conditions for the more nutritious C3 plants. Production of offspring was strongly and positively correlated with C3 resource use as indicated by δ13C values in metabolically active tissues (plasma and red blood cells), but not with δ13C values in adipose tissues used for long-term energy storage, or with foraging niche widths. These findings demonstrate that assimilation of energy from C3 plants is associated with increased reproductive output and that drought conditions importantly constrain the resource base available to C. gunnisoni. The link between plant nutritional quality and demographic parameters highlights the role of abiotic regulation within this reportedly disease-limited species. [ABSTRACT FROM AUTHOR]

Vigilance is important for survivorship and reproductive success and is common and conspicuous within hundreds of species across a diverse array of taxa. Vigilance can involve either scanning for predators (antipredator vigilance) or watching conspecifics (social vigilance). From observations of marked Gunnison's prairie dogs, Cynomys gunnisoni (Sciuridae), living under natural conditions at Valles Caldera National Preserve, New Mexico, U.S.A., we compared results from the two most common sampling methods used by behavioural ecologists to measure vigilance: focal sampling (i.e. observing an individual for a specific amount of time and recording the amount of time spent vigilant) and scan sampling (i.e. observing all individuals in an area at a single moment and recording whether each individual at that moment is vigilant or nonvigilant). Information from different individuals and from the same individuals over time both revealed that estimates of vigilance from scan sampling were consistently and significantly higher than estimates from focal sampling. These differences probably resulted because nonvigilant behaviours were more difficult to detect in scan samples than in focal samples. Our results have important implications for behavioural ecologists who want to make intraspecific or interspecific comparisons of vigilance. [ABSTRACT FROM AUTHOR]

Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog ( Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus ( DRB1) in Gunnison's prairie dog ( C. gunnisoni) and quantified population genetic structure at the DRB1 versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman ( SE) and Espee Ranch ( ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley ( AV). We found fairly low allelic diversity at the DRB1 locus, with one allele ( DRB1*01) at high frequency (0.67-0.87) in all colonies. Two other DRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog ( C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus ( FST = 0.033) than at microsatellite markers ( FST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced the DRB1 locus because its level of differentiation was not different from that of microsatellites in an FST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60 C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele ( DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival. [ABSTRACT FROM AUTHOR]

The Gunnison's Prairie Dog (GPD, Cynomys gunnisoni) is an herbivorous, burrowing rodent that was extirpated from the Sevilleta National Wildlife Refuge in the 1930's by ranchers to make land available for grazing livestock. Currently, the GPD is the subject of a long-term reintroduction experiment overseen by the U.S. Fish and Wildlife Service. The burrowing and feeding habits of the GPD influences an ecosystem's biotic and abiotic factors significantly, making this species a keystone ecosystem engineer that plays a vital role creating heterogeneous mosaics of habitat. Their presence is correlated with diverse biological communities and maintenance of grassland ecosystems. To better understand the impact of GPDs on small mammal population and diversity, we compared control sites to prairie dog reintroduction sites using a mark-recapture methodology with live trapping of animals on all plots. After placing Sherman traps on all sites over a four-week period, we compared data from previous trapping seasons to measure the long-term effects of the reintroduction on small mammal populations. We hypothesized that sites with reintroduced prairie dogs would have a higher diversity and abundance of small mammals compared to that of the control sites. Our results demonstrate that diversity and abundance is higher overall in treatment plots than in controls over multiple trapping seasons, confirming the importance of a keystone species in an ecosystem. [ABSTRACT FROM AUTHOR]

Gunnison's prairie dogs ( Cynomys gunnisoni) have been considered at greater risk from Yersinia pestis (plague) infection in the montane portion of their range compared to populations at lower elevations, possibly due to factors related to flea transmission of the bacteria or greater host susceptibility. To test the latter hypothesis and determine whether vaccination against plague with an oral sylvatic plague vaccine (SPV) improved survival, we captured prairie dogs from a C. g. gunnisoni or 'montane' population and a C. g. zuniensis or 'prairie' population for vaccine efficacy and challenge studies. No differences ( P = 0.63) were found in plague susceptibility in non-vaccinated animals between these two populations; however, vaccinates from the prairie population survived plague challenge at significantly higher rates ( P < 0.01) than those from the montane population. Upon further analysis, we determined that response to immunization was most likely associated with differences in age, as the prairie group was much younger on average than the montane group. Vaccinates that were juveniles or young adults survived plague challenge at a much higher rate than adults ( P < 0.01 and P = 0.02, respectively), but no difference ( P = 0.83) was detected in survival rates between control animals of different ages. These results suggest that host susceptibility is probably not related to the assumed greater risk from plague in the C. g. gunnisoni or 'montane' populations of Gunnison's prairie dogs, and that SPV could be a useful plague management tool for this species, particularly if targeted at younger cohorts. [ABSTRACT FROM AUTHOR]

The article presents a case study which investigates the effectiveness of the RCN-F1/V307 vaccine in protecting the prairie dog population from plague diseases which includes the raccoon pox virus. Topics discussed include the use of treated baits, wildlife observation and collection techniques in the study, the use of the statistical package R (version 2.15.2) in the analysis of the acquired data, and a detailed analysis of the results.

Highlights: [•] Multiple criteria and analyses should be used to delineate subspecies taxonomy. [•] Gunnison’s prairie dogs (GUPD) provide a case study for intraspecific taxonomy. [•] GUPD comprise genetically, morphologically and ecologically distinct subspecies. [•] The boundary between subspecies requires revision to reflect observed differentiation. [ABSTRACT FROM AUTHOR]

Understanding patch dynamics can help scientists better understand metapopulations and the relationships of animals that share a hábitat. The Burrowing Owl {Athene cunicularia) is a well-known associate of prairie dog colonies, thereby linking conservation measures that benefit these species. We used occupancy modeling to determine how colony attributes (e.g., size and edge effects) and the loss of prairie dog colonies to sylvatic plague affected the occupancy of those colonies by Burrowing Owls in north-central Montana. We surveyed presence-absence of Burrowing Owls during a 13-yr period (1995-2007) and analyzed the data using a robust-design occupancy model in Program MARK. The proportion of colonies occupied by Burrowing Owls ranged from 0.41 to 0.54 across years while the probability of detecting the owls ranged from 0.22 to 0.92. Contrary to our predictions, colony edge effects and plague epizootics showed only weak or no effects on Burrowing Owl occupancy. Prairie dog colony size had the greatest effect on Burrowing Owl occupancy patterns. Colonization of prairie dog colonies by owls generally increased with colony area, whereas owl extinction initially dropped and then increased as a function of increasing colony area. We found no direct link between Burrowing Owl occupancy of prairie dog colonies and plague history, but our results reaffirmed the importance of colony size. Collectively, this information will help inform future conservation efforts for Burrowing Owls that occupy prairie dog colonies. [ABSTRACT FROM AUTHOR]

ABSTRACT Burrowing, herbivorous mammals play important roles as ecosystem engineers and keystone species of grassland ecosystems around the world, but populations of many species have declined dramatically because of myriad threats from human activities. Prairie dogs ( Cynomys spp.) play important roles in shaping the central grasslands of North America, and have declined by about 98% across their range, with consequent losses in associated species and grassland habitat. This has prompted much interest in restoring their populations to protected areas. Managers lack a clear understanding of the long-term success of reintroductions, however, and how success may vary across different species of prairie dogs and their widespread geographic ranges. We reintroduced over 1,000 Gunnison's prairie dogs ( C. gunnisoni) to a semi-arid grassland ecosystem in the southern portion of their range in central New Mexico, USA, and used standard capture-recapture methods to study their population dynamics over a period of 8 years. Mean adult survival was 27% over the course of the study, with precipitation identified as the primary driver of survival. Estimated survival was below 12% during severe drought periods and during the first few years following initial reintroduction, the latter likely because of high predation. Consequently, multiple releases of animals were required to prevent extirpation, and the long-term sustainability of this population remains questionable. Over the 8 years of our study, our site experienced 4 severe droughts during spring, the key period for prairie dog mating, pregnancy, and lactation. Production of offspring at the site was low, likely because of the dry and variable conditions that occurred. We show that prairie dog restoration in semi-arid grassland environments that are typical of the lower elevations and southern extent of their range may not succeed in producing viable colonies, and that dedicated management for multiple years is needed to counteract periods of slow or negative population growth. Our findings underscore the importance of maintaining and expanding existing colonies wherever possible in these more arid regions, and suggest that reintroductions should be treated as a secondary management strategy. Our work also reveals the high vulnerability of prairie dog population extinction due to drought, which has important implications for Gunnison's prairie dog conservation under a warming and drying climate. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Some animals have the capacity to produce different alarm calls for terrestrial and aerial predators. However, it is not clear what cognitive processes are involved in generating these calls. One possibility is the position of the predator: Anything on the ground receives a terrestrial predator call, and anything in the air receives an aerial predator call. Another possibility is that animals are able to recognize the physical features of predators and incorporate those into their calls. As a way of elucidating which of these mechanisms plays a primary role in generating the structure of different calls, we performed two field experiments with Gunnison's prairie dogs. First, we presented the prairie dogs with a circle, a triangle, and a square, each moving across the colony at the same height and speed. Second, we presented the prairie dogs with two squares of differing sizes. DFA statistics showed that 82.6 percent of calls for the circle and 79.2 percent of the calls for the triangle were correctly classified, and 73.3 percent of the calls for the square were classified as either square or circle. Also, 100 percent of the calls for the larger square and 90 percent of the calls for the smaller square were correctly classified. Because both squares and circles are features of terrestrial predators and triangles are features of aerial predators, our results suggest that prairie dogs might have a cognitive mechanism that labels the abstract shape and size of different predators, rather than the position of the predator. [ABSTRACT FROM AUTHOR]

Aboveground mounds and underground burrows are multifunctional and influence behavior and habitat of Gunnison's prairie dogs (Cynomys gunnisoni). Four colonies were studied June-September 2004 to examine function of mounds with respect to vigilance for predators, and to estimate magnitude of soil mixed by these prairie dogs. Frequency of vigilance atop mounds increased in taller vegetation and individuals at perimeters of colonies oriented toward the outside more frequently than to the interior of colonies. Mounds accounted for an average of 10,374 kg of soil/ha that was excavated from the burrow. This mass of subsoil moved to the surface and the 7-17 m³ of air in the burrow make the geomorphic effect of prairie dogs potentially significant. [ABSTRACT FROM AUTHOR]

Translocating prairie dogs from areas in or near human developments to wildlands can reduce conflicts with humans or supplement wild populations, but translocation methods differ in cost and fate of translocated individuals is often difficult to assess. We translocated 74 Gunnison's prairie dogs from 1 source colony in downtown Flagstaff, Arizona (urban) and 75 from 1 source colony in lower density housing outside the city (suburban) to 2 abandoned, recipient colonies on open grasslands 50 km north of the city (wildland). We released animals into uncaged, pre-existing burrow entrances (hard release) or into temporary cages over pre-existing burrow entrances (soft release). We captured 15 (10%) marked animals 1 year post-translocation at the 2 recipient colonies, 7 from soft release treatments and 8 from hard release treatments but visual surveys indicated a minimum of 57 adult prairie dogs and 76 pups present. Adult prairie dogs in all photographs taken by automated cameras placed at burrow entrances at each recipient colony had ear tags, suggesting that most animals at these colonies were survivors from translocation and that survival was likely higher than 10%. By 1 year post-release, recipient colonies occupied an area roughly 9-18 times that of source colonies. Urban Gunnison's prairie dogs can be successfully translocated to abandoned wildland colonies without using soft release methods, but animals may disperse widely. Given the cost and effort translocation requires, and the fact that all 6 confirmed mortalities were from human shooting, we recommend temporary restrictions on shooting at recipient colonies until populations have met management goals. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Areas occupied by white-tailed prairie dogs (WTPD; Cynomys leucurus) and Gunnison's prairie dogs (GPD; C. gunnisoni) are not well-known in Colorado (USA) and elsewhere. Suitable methodology for monitoring changes in populations of WTPD and GPD over broad areas also has not been well established. We evaluated occupancy modeling methodology to establish baseline occupancy rates for WTPD and GPD in Colorado. We estimated that WTPD occupied 24.1% (SE=12.8) of 47,710 0.25-km² plots and GPD occupied 7.5% (SE=1.3) of 158,225 0.25-km² plots in Colorado during 2004 and 2005. Areas reported as colonies in the Colorado Division of Wildlife's database were not good predictors of WTPD and GPD occupancy. Occupancy rates were highest for GPD at intermediate elevations. We estimated detection probabilities for surveys from the ground of 0.760 (SE=0.042) for WTPD and 0.786 (SE=0.060) for GPD. Probability of detection for WTPD improved with lower temperature and earlier Julian date, whereas no covariates improved detection rates for GPD. We recommend that wildlife managers use occupancy monitoring to establish status and trends in populations of WTPD and GPD across their range. [ABSTRACT FROM AUTHOR]

In this study, we describe patterns of relatedness in Gunnison’s prairie dog ( Cynomys gunnisoni) social groups. Kin selection is often cited as a mechanism for the evolution and maintenance of social groups, and Gunnison’s prairie dog females are occasionally described as being strongly philopatric. Overall, randomization tests revealed that females within territorial groups were not more closely related to each other than expected at random. A similar pattern was found among males and between males and females, indicating that there was no sex-biased dispersal occurring in these populations. Ecological variables measured in this study, such as food abundance and food dispersion, were not correlated with relatedness. In addition, territory size and density/m2 did not correlate significantly with relatedness. Although there was variability in the spatial overlap among individuals within groups, there was no indication that relatedness explained this variation. These results suggest that kin selection is not maintaining social groups in these populations, but that competition for access to resources required by both males and females may explain dispersal and social group patterns in these populations. [ABSTRACT FROM AUTHOR]

Abstract: Ecosystem engineering by animals can create new habitats and increase the heterogeneity of the habitat mosaic that in turn can increase plant and animal diversity. Prairie dogs in North America alter both the above- and below-ground structure of the landscape and create novel habitats in grassland ecosystems. The ground-dwelling arthropod community associated with Gunnison''s prairie dog modified habitats is compositionally different from that found in the surrounding grassland. Individual arthropod families and species have different distributions in both active prairie dog towns and inactive towns, compared to unmodified grasslands. These different responses to ecosystem engineering increase beta (between-habitat) and gamma (regional) diversity. This study suggests that simple measures of alpha diversity (species richness) may not adequately quantify overall diversity and that measures of beta diversity may be necessary to assess the role of prairie dogs as keystone engineers. Thus, conservation of prairie dogs and the engineering process may have positive effects for numerous species both locally and regionally. [Copyright &y& Elsevier]

Abstract: Although the five species of prairie dogs (Cynomys spp.) are recognized as important components of grassland ecosystems in western North America, they have experienced major population declines due to poisoning, outbreaks of sylvatic plague, recreational shooting, and habitat conversion. From May 2000 to October 2001, we investigated 270 colonies of Gunnison’s prairie dog (Cynomys gunnisoni) in Arizona. Because these colonies were classified as active in previous surveys (1987, 1990–1994, 1998), we were able to examine their persistence. Most (70%) of the colonies became inactive between the initial and recent surveys, with colony extinctions spanning our study area. Colony persistence was positively associated with the persistence of the nearest neighboring colony but was not associated with major vegetation type, distance to nearest neighboring colony, or initial size of the colony. The amount of area occupied by individual colonies varied between surveys, sometimes dramatically. We found little evidence that the reduction in active colonies was due to poisoning, recreational shooting, or habitat conversion. Rather, direct and indirect evidence suggest plague is the primary factor negatively impacting Gunnison’s prairie dog populations in Arizona. Currently, there is no way to control or prevent plague outbreaks in Gunnison’s prairie dog populations. To mitigate the effects of localized plague outbreaks on the overall population of this species, we suggest that Gunnison’s prairie dog be reintroduced to public lands throughout its historical range. [Copyright &y& Elsevier]

Acoustic structures of sound in Gunnison’s prairie dog alarm calls are described, showing how these acoustic structures may encode information about three different predator species (red-tailed hawk—Buteo jamaicensis; domestic dog—Canis familaris; and coyote—Canis latrans). By dividing each alarm call into 25 equal-sized partitions and using resonant frequencies within each partition, commonly occurring acoustic structures were identified as components of alarm calls for the three predators. Although most of the acoustic structures appeared in alarm calls elicited by all three predator species, the frequency of occurrence of these acoustic structures varied among the alarm calls for the different predators, suggesting that these structures encode identifying information for each of the predators. A classification analysis of alarm calls elicited by each of the three predators showed that acoustic structures could correctly classify 67% of the calls elicited by domestic dogs, 73% of the calls elicited by coyotes, and 99% of the calls elicited by red-tailed hawks. The different distributions of acoustic structures associated with alarm calls for the three predator species suggest a duality of function, one of the design elements of language listed by Hockett [in Animal Sounds and Communication, edited by W. E. Lanyon and W. N. Tavolga (American Institute of Biological Sciences, Washington, DC, 1960), pp. 392–430]. [ABSTRACT FROM AUTHOR]

The newly described Gunnison sage-grouse (Centrocercus minimus) is a species of concern for management because of marked declines in distribution and abundance due to the loss and fragmentation of sagebrush habitat. This has caused remaining populations to be unusually small and isolated. We utilized mitochondrial DNA sequence data and data from 8 nuclear microsatellites to assess the extent of population subdivision among Gunnison sage-grouse populations in southwestern Colorado and southeastern Utah, USA. We found a high degree of population structure and low amounts of gene flow among all pairs of populations except the geographically adjacent Gunnison and Curecanti populations. Population structure for Gunnison sage-grouse was significantly higher than has been reported for greater sage-grouse (C. urophasianus). Further, we documented low levels of genetic diversity in some populations (particularly Dove Creek/Monticello and Piñon Mesa with an avenge of only 3.00 and 2.13 alleles per locus respectively) indicating that translocations from larger, more genetically diverse populations may be warranted, Bayesian analysis identified 3 potential migrants (involving San Miguel, Dove Creek/Monticello, Crawford, and Curecanti). Further, this analysis showed that 4 individuals from Cerro/Cimarron were more closely related to birds from San Miguel than to its geographically closer neighbors Gunnison and Curecanti. This suggests the Cerro/Cimarron area may act as a stepping stone for gene flow between San Miguel and Gunnison and that habitat restoration and protection in areas between these 2 basins should be a priority in an attempt to facilitate natural movement among these populations. Conservation plans should include monitoring and maintaining genetic diversity, preventing future habitat loss and fragmentation, enhancing existing habitat, and restoring converted sagebrush communities. [ABSTRACT FROM AUTHOR]

Prairie dog (Cynomys spp.) populations have been reduced by 98% compared to historical levels because of widespread poisoning, habitat loss, recreational shooting, and outbreaks of sylvatic plague (Yersinia pestis). Our objectives were to identify habitat correlates of Gunnison's prairie dog (C. gunnisoni) colonies and to develop a predictive logistic regression model to identify potential reintroduction sites for this species. During 2000 and 2001, we examined habitat features at 50 Gunnison's prairie dog colonies and 50 paired random sites in northern Arizona, USA. When compared to random sites, Gunnison's prairie dog colonies had deeper soils, less variability in slope, and less rock ground cover. Our results suggest the importance of deep soils for allowing Gunnison's prairie dogs to establish hibernacula below the frost line. Our model allows prediction of the probability, of Gunnison's prairie dog presence at a site based on soil depth, standard deviation of slope, and surface rock cover, and should aid managers in reestablishing this species throughout its historical range. [ABSTRACT FROM AUTHOR]

Body mass is sexually dimorphic and varies seasonally for all 5 species of prairie dogs (Sciuridae: Cynomys), as shown by data from live individuals over a period of 28 years (1974-2001; n = 16,447 body masses). Sexual dimorphism (i.e., body mass of males as percentage of body mass of females) during the breeding season is 105% for black-tailed prairie dogs, 127% for Utah prairie dogs, 131% for Gunnison's prairie dogs, and 136% for white-tailed prairie dogs. Sexual dimorphism is minimal at the end of the breeding season, when exhausted males are thin and early-breeding females are heavy with pregnancy. Sexual dimorphism is maximal at weaning, when rested, well-fed males are heavy and females are emaciated from lactation. The most likely ultimate causation for sexual dimorphism among prairie dogs is sexual selection. [ABSTRACT FROM AUTHOR]

Feasibility of assigning parentage using variable microsatellite loci was assessed for 2 species of prairie dogs. Parentage was determined from 7 microsatellite loci for 46% of juveniles born during 1994 in a colony of Gunnison's prairie dogs (Cynomys gunnisoni), and for 53% and for 45% of juveniles born during 1996 and 1997, respectively, in a colony of Utah prairie dogs (C. parvidens). Frequency of multiple paternity estimated for Gunnison's (77%) and Utah (71% and 90%) prairie dogs was greater than that detected previously for black-tailed prairie dogs (5%-10%) but within the range reported for other grounddwelling squirrels. Of the 84 adult females and 33 adult males present during 1994 in the colony of Gunnison's prairie dogs, 75 (89%) and 22 (67%), respectively, produced weaned offspring. Breeding success for Utah prairie dogs was relatively low in 1996 (45% for females and 32% for males) but increased in 1997 (80% for females and 81% for males). [ABSTRACT FROM AUTHOR]

We examined the relationship between habitat structure and alarm call characteristics in six colonies of Gunnison's prairie dogs (Cynomys gunnisoni) near Flagstaff, Arizona, before and after a mid-summer vegetation change. We found significant differences in alarm call characteristics between colonies, confirming the existence of alarm call dialects. Differences in frequency components but not temporal components of calls were associated with differences in habitat structure. Playback experiments revealed that differences in alarm call structure affected acoustic transmission of calls through the local habitat. Thus, we identify habitat structure as one factor that may contribute to alarm call differences between colonies of Gunnison's prairie dogs. Relationships between call characteristics and habitat structure changed over seasons. Playback experiments suggested that this changing relationship could reflect a change in the purpose of the alarm call between early and late summer. Some components of alarm calls seem tailored for attenuation over short distances in the early summer but for long-distance transmission at summer's end. These differences might arise because pups stay close to their natal burrows in the early summer and disperse throughout a colony in late summer. Alternatively, these differences in alarm call transmission between seasons could be caused by the increase in vegetation in the mid-summer. At the end of the summer prairie dogs could be more dependent on long-distance antipredator calls to offset the loss of visibility caused by the increase in vegetation in the late summer. [ABSTRACT FROM AUTHOR]

Vector-borne disease prevention and control strategies, aside from those associated with domestic rodents, have rarely involved management of vertebrate populations, even though in many cases such management would appear to represent the most effective and economical long-term approach. Prevention of a long list of arthropod transmitted diseases ls often at best a stop-gap procedure undertaken only after substantial disease hazard is detected in reservoir populations. More often, control actions await the detection of human cases, at which time short-term emergency control measures may be conducted, usually involving the use of toxicants against arthropod vectors and occasionally vertebrate reservoirs. In some cases, action is not taken because techniques are not available, but more often the decisive factors in action versus inaction are economic, jurisdictional, and/or organizational. Often, public health problems proceeding from unmanaged vertebrate populations are (justifiably) given low priority on the basis of costs versus benefits. If the same populations constitute a problem for health, economic, wildlife, or recreational interests, it may behoove us to pool our priorities, skills, and resources in collaborative management program designed for the greatest overall benefit rather than to proceed only on those programs that can be justified on the basis of one special Interest.

An introduction to the journal is presented in which the editor discusses various reports within the issue on topics including referentiality in the alarm calling systems of new world primates, vertebrate distress calls, and variation in Gunnison's prairie dog alarm call structure.

The article discusses research conducted by Northern Arizona University animal behaviorist Con Slobodchikoff and colleagues on the alarm calls issued by the Gunnison prairie dog. The calls were found to send information about the color of a predator. This is not completely peculiar to prairie dogs, as animals such as ground squirrels and black-capped chickadees also convey information on predators. University of Manitoba ecologist James Hare provides quotes.