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Animal mating systems have fascinated biologists for thousands of years. Ways to describe a mating system include determining social organization, observing copulations, or using genetics to assign parentage. Social organization can be difficult to quantify, however, documentation of copulations is often challenging, many copulations do not produce offspring, and genetic variation is sometimes minimal. Here we use data from a 7-year study of wild white-tailed prairie dogs (WTPDs, Cynomys leucurus) living in Colorado USA to estimate the frequencies of polyandry (i.e., copulation with ≥2 males) and polygyny (i.e., copulation with ≥2 females) from three independent approaches: (1) determination of the number of males and females living in the same territory (social organization); (2) observations of copulations; and (3) genetic assignments of paternity from seven polymorphic microsatellites. We predicted that our three approaches would yield similar estimates of polyandry and polygyny. Because a WTPD female's period of sexual receptivity each spring is limited to several hours on a single day, we also predicted that frequencies of polyandry and polygyny would be lower for WTPDs than for animals with longer periods of receptivity. Our results did not support these predictions. For polyandry, observations of copulations and genetics indicated similar overall percentages (27%), but social organization indicated a much lower percentage (3%). For polygyny, observations of copulations indicated the highest overall percentage (84%), then social organization (59%), then genetics (46%). All three approaches showed striking annual variation in the frequencies of WTPD polyandry and polygyny. Long-term studies that integrate behavioral and genetic insights can provide a detailed view of a mating system, but feasibility will depend on ease of capture, visibility of copulations, length of mating season, research objectives, and genetic variation.

In 2008 and 2009, we evaluated the duration of prophylactic deltamethrin treatments in white-tailed prairie dog ( Cynomys leucurus) colonies and compared effects of autumn or spring dust application in suppressing flea numbers and plague. Plague occurred before and during our experiment. Overall, flea abundance tended to increase from May or June to September, but it was affected by deltamethrin treatment and plague dynamics. Success in trapping prairie dogs (animals caught/trap days) declined between June and September at all study sites. However, by September trap success on dusted sites (19%; 95% confidence interval [CI] 16-22%) was about 15-fold greater than on undusted control sites (1%; CI 0.3-4%; P≤0.0001). Applying deltamethrin dust as early as 12 mo prior seemed to afford some protection to prairie dogs. Our data showed that dusting even a portion of a prairie dog colony can prolong its persistence despite epizootic plague. Autumn dusting may offer advantages over spring in suppressing overwinter or early-spring flea activity, but timing should be adjusted to precede the annual decline in aboveground activity for hibernating prairie dog species. Large colony complexes or collections of occupied but fragmented habitat may benefit from dusting some sites in spring and others in autumn to maximize flea suppression in a portion of the complex or habitat year-round. [ABSTRACT FROM AUTHOR]

The article presents the evaluation of bait distribution strategies for the delivery of an oral vaccine to prairie dogs or Cynomys species against the zoonotic disease plague. It talks about the use of biomarker and rhodamine B. The results of distributing baits around active burrows or along transects at different densities are presented. Also included are the findings of the bait uptake by the four species of prairie dogs and other species of small mammals.

Vigilance for predators is omnipresent among species of prey. We report an investigation of vigilance of white-tailed prairie dogs (Sciuridae: Cynomys leucurus) living under natural conditions. Our most important conclusion concerns variation in vigilance within and among uniquely marked adult individuals (n = 53 in 2007, n = 62 in 2008). Within a single day, the percentage of observations when an individual was scanning for predators ranged from 0-100%, with a mean of 24.4%. Over a period of 3 months, some individuals were vigilant for <5% of observations, but others were vigilant for >50% of observations. For 12 of 24 individuals that we monitored for vigilance in consecutive years, levels of vigilance were significantly different between years. Some of the variation within and between individuals might have resulted from differences in vulnerability to predation. [ABSTRACT FROM AUTHOR]

Multi-opening burrow systems constructed by prairie dogs (Cynomys) ostensibly provide escape routes when prairie dogs are pursued by predators capable of entering the burrows, such as black-footed ferrets (Mustela nigripes), or by predators that can rapidly dig into the tunnels, such as American badgers (Taxidea taxus). Because badgers also prey on ferrets, ferrets might similarly benefit from multi-opening burrow systems. Using an air blower, white-tailed prairie dog (Cynomys leucurus) burrow openings were tested for connectivity on plots occupied by black-footed ferrets and on randomly selected plots in Wyoming. Significantly more connected openings were found on ferret-occupied plots than on random plots. Connected openings might be due to modifications by ferrets in response to plugging by prairie dogs, due to selection by ferrets for complex systems with multiple openings that are already unobstructed, or simply due to ferrets lingering at kill sites that were multi-opening systems selected by their prairie dog prey. [ABSTRACT FROM AUTHOR]

Black-footed ferrets (Mustela nigripes) often hunt at night, attacking normally diurnal prairie dogs (Cynomys spp.) in underground burrow systems. While monitoring black-footed ferrets in South Dakota during morning daylight hours, we observed an adult female ferret ambush a black-tailed prairie dog (C. ludovicianus) emerging from a burrow. On a neighboring colony, we observed a second adult female ferret engaging in similar ambush behaviors on 12 occasions, although prey was not visible. We retrospectively assessed radio-telemetry data on white-tailed prairie dogs (C. leucurus) and a male and a female ferret to evaluate ferret activity in relation to timing of prairie dog emergence. Activity of radio-collared ferrets was high during the hourly period when prairie dogs first emerged and the following 2 hr, relative to later daylight hours. Such behavior is consistent with behaviors observed in South Dakota. Nighttime movements by ferrets might involve hunting but also reconnaissance of prey preparatory to morning ambush attacks. [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]

Hibernating mammals have the remarkable ability to withstand long periods of fasting and reduced activity with dramatic maintenance of skeletal muscle function and protein composition. We investigated several hindlimb muscles of white-tailed prairie dogs ( Cynomys leucurus) and black bears ( Ursus americanus), two very different hibernators who are dormant and fasting during winter. The black-tailed prairie dog ( C. ludovicianus) remains active during winter, but suffers minor skeletal muscle atrophy; nevertheless, they also demonstrate apparent skeletal muscle adaptations. Using SDS-PAGE, we measured myosin protein isoform profiles before and after the hibernation season. All species maintained or increased levels of slow myosin, despite the collective physiological challenges of hypophagia and reduced activity. This contrasts markedly with standard mammalian models of skeletal muscle inactivity and atrophy predicting significant loss of slow myosin. A mechanism for changes in myosin isoforms was investigated using reverse-transcription PCR, following partial sequencing of the adult MHC isoforms in C. leucurus and U. americanus. However, mRNA expression was not well correlated with changes in MHC protein isoforms, and other synthesis and degradation pathways may be involved besides transcriptional control. The muscles of hibernating mammals demonstrate surprising and varied physiological responses to inactivity and atrophy with respect to slow MHC expression. [ABSTRACT FROM AUTHOR]

In a 6-yr study, I investigated possible selective bases for coloniality in two species of squirrels (Sciuridae): loosely colonial White-tailed Prairie Dogs (Cynomys leucurus) and densely colonial Black-tailed Prairie Dogs (C. ludovicianus). White-tail study sites were in Wyoming and Colorado, USA; Black-tail study sites were in Colorado and South Dakota. I examined three hypotheses that might explain the evolution of coloniality: (a) shortage of suitable habitat, (b) social facilitation of foraging, and (c) reduced predation. The apparent surplus of unused suitable habitat and the absence of isolated individuals both indicated that prairie dogs are not forced to live together because of habitat shortages. An analysis of prairie dog foraging patterns indicated that there is no social facilitation of foraging in terms of either (a) group hunting of either large or elusive prey, (b) the location of large, scattered food supplies, (c) modification of the soil in order to effect the growth of vegetation that is more favorable or more abundant than that which would otherwise result, or (d) group defense of foraging grounds. Three lines of evidence indicate that reduced predation may be the most important benefit of prairie dog coloniality. First, simulated predatory attacks by badgers (Taxidea taxus) indicated that individuals in large wards (subcolonies) detect predators more quickly than do individuals in smaller wards; further, Black-tails detect predators more quickly than do White-tails. Second, individuals in large wards devote proportionately less time to alertness (i.e., scanning for predators) than do individuals in smaller wards, and Black-tails are less vigilant than are White-tails. Third, breeding synchronization and center-edge differences in individual alertness both indicate the possible importance of self herd effects. Interspecific differences in ward size and ward density may ultimately result because White-tail habitats contain significantly more protective cover than do Black-tail habitats. [ABSTRACT FROM AUTHOR]

The mitochondrial genomes of the white - tailed praire dogCynomys leucurusand black-tailed prairie dogC. ludovicianus(Rodentia: Sciuridae) are circular molecules of 16,454 bp and 16,466 bp in length, respectively, containing 37 genes as in other Rodentia species. The A + T content of the overall base composition of the H-strand is 63.0% and 62.6% forC. leucurusandC. ludovicianus,respectively. The control region of theC. leucurusandC. ludovicianusmt genome is 1012 bp in length, and the A + T content of this region is 63.5% and 62.0%, respectively. Nucleotide sequence divergence of the mt genome (pdistance) betweenC. leucurusandC. ludovicianuswas 4.0%. [ABSTRACT FROM AUTHOR]