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1.
Eight bobcats with adjoining or overlapping home ranges were examined. Hematological values were within previously reported ranges. Six bobcats demonstrated antibody titers to Toxoplasma gondii. Isospora spp., Taenia taeniaeformis, Spirometra mansoides, Physoloptera rara, Toxocara cati, Strongyloides spp., Trichurus spp., Capillaria spp., and Ancyclostoma spp. were found also in the animals examined. The mean number of parasite species per host was 4.1. All bobcats tested negative for serum antibodies to Rocky Mountain spotted fever (Rickettsia rickettsii). Two bobcats had titers less than or equal to 1:20 for tularemia (Francisiella tularensis), and two were positive for leptospirosis (Leptospira spp.).  相似文献   

2.
Bobcats are opportunistic felids occurring in a diverse range of habitats and with a widespread distribution from southern Canada to southern Mexico. To explore why the bobcat's distribution stops at the Isthmus of Tehuantepec, we modelled the ecological niches, projected as potential distributions, of the felid community (bobcat Lynx rufus, puma Puma concolor, jaguar Panthera onca, margay Leopardus wiedii, jaguarundi Herpailurus yagouaroundi, and ocelot Leopardus pardalis) in southern Mexico, using occurrence data, environmental maps, the computer algorithm GARP, and a GIS platform. The resulting geographical projection of the ecological niche of bobcats extends south of the Isthmus of Tehuantepec, suggesting that ecological conditions exist for the establishment of populations. The overlap of the modelled distribution of the bobcat was large with that of the puma (97%), but low with that of the ocelot (44%), margay (46%), jaguar (49%), and jaguarundi (52%), the latter three having relatively similar size and feeding habits to bobcats. Moreover, an independent analysis computing a geographic co‐occurrence index showed a similar trend of geographic avoidance (values 0.15), while all felids, except bobcats, showed a geographic co‐occurrence in southern Mexico (values ranging from ?1.91 to 4.71). The Isthmus of Tehuantepec, a lowland region with subtropical habitat, is unlikely to serve as a geographic and ecological barrier to bobcats. As mammal inventories have been conducted for over a century in this region with no records of bobcats, it is unlikely that bobcats are present but have just not been seen. Fossil records also provide no support for the presence of bobcats in that region in the past. Thus, competitive interactions with other felid species appear important in limiting the southern distribution of bobcats, preventing dispersal to a suitable but geographically reduced area south of the Isthmus of Tehuantepec.  相似文献   

3.
We combined observations of bobcats (Lynx rufus) from bowhunters with remotely-sensed data to build models that describe habitat and relative abundance of this species in the agricultural landscape of Iowa, USA. We calculated landscape composition and configuration from publicly available land cover, census, road, hydrologic, and elevation data. We used multiple regression models to examine county-level associations between several explanatory variables and relative abundance of bobcats reported by surveyed bowhunters in each county. The most influential explanatory variables in the models were metrics associated with the presence of grassland, including Conservation Reserve, along with configuration of this perennial habitat with forests, although human population density and abundance of eastern cottontails (Sylvilagus floridanus) also correlated with abundance of bobcats. Validation of predictions against 3 years of independent data provided confidence in the models, with 66% of predictions within 1 bobcat/1,000 hunter-hours and 95% within 5 bobcats/1,000 hunter-hours of observed values. Once we accounted for landscape differences, no residual spatial trend was evident, despite relatively recent bobcat recolonization of Iowa. Models suggested that future range expansion of the bobcat population may be possible in some northern Iowa counties where habitat composition is similar to counties in southern Iowa where bobcats are abundant. Results from the county-level model have been useful to the Iowa Department of Natural Resources in evaluating the expansion of this once rare species and for delineating harvest opportunities. © 2011 The Wildlife Society.  相似文献   

4.
The stomachs and proximal duodena of 160 cougars (Puma concolor) and 17 bobcats (Lynx rufus), obtained throughout Oregon during 7 yr, were examined for Cylicospirura spp. and associated lesions. Prevalence in cougars was 73%, with a range in intensity of 1-562 worms. The mean diameter of nodules was 1.2 cm (SD=0.5), and many extended through the submucosa to the muscularis. About 83% of cougars had nodules; most nodules contained worms, but 14% of the smaller nodules (<0.2 cm) contained porcupine (Erethizon dorsatum) quills. A mean of 12.4 worms/nodule (SD=34.1) was observed, with a maximum of 340 worms/nodule. Prevalence in bobcats was 53%, with an intensity of 1-25 worms. About 65% of bobcats had nodules, which were slightly smaller than those in cougars but appeared to involve similar layers of gastrointestinal tissue. One to 25 Cylicospirura sp. were found in all but two small nodules in bobcats. Cougars killed for livestock damage or safety concerns had a significantly higher median worm intensity than did those that died of other causes. Also, the median worm intensity of older cougars was higher than that of younger lions. There were more males than females killed for livestock damage or safety concerns. The cylicospirurid from cougars was Cylicospirura subaequalis, and that of bobcats was Cylicospirura felineus. These two similar species were separated morphologically by differences in tooth and sex organ morphology. They were also differentiated by DNA sequence analysis of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). Worm sequences from cougars differed from those from bobcats by 11%, whereas essentially no difference was found among worms from the same host. Phylogenetic analysis showed that within the order Spirurida, both cylicospirurids were most closely related to Spirocerca lupi, based on this gene sequence.  相似文献   

5.
6.
Sarcocysts were found in the tongue, diaphragm, heart, intestinal tunica muscularis, and skeletal muscle of bobcats (Felis rufus floridanus) collected in Florida (USA). The tongue was found to be the best indicator tissue for sarcocysts (P less than 0.005). Thirty of 60 bobcats screened were found to contain sarcocysts in at least one of the muscle tissues examined. Of the positive bobcats, 28 of 28 tongues contained sarcocysts, while only 10 of 27 (37%), and 8 of 26 (31%) contained sarcocysts in the diaphragm or cardiac muscle, respectively. Although immune suppression has been suggested as a possible reason for formation of sarcocysts in some carnivores, no such correlation was evident in the bobcats. Comparisons of prey species taken by the panther and bobcat, and overlap of geographical range by the two species leave questions as to the source of infection, and the species of Sarcocystis that is infecting both felids.  相似文献   

7.
Exposure of bobcats (Lynx rufus) and gray foxes (Urocyon cinereoargenteus) to a range of common canine and feline pathogens was assessed in urban and rural zones of Golden Gate National Recreation Area, a National Park in the San Francisco Bay Area, (California, USA) from 1992 to 1995. Testing included serology for canine distemper virus, canine parvovirus (CPV), canine adenovirus, Leptospira interrogans, feline calicivirus (FCV), feline panleukopenia virus, feline herpesvirus, feline enteric coronavirus (FECV), feline immunodeficiency virus, feline leukemia virus, Toxoplasma gondii, and Bartonella henselae. Testing was also performed for Dirofilaria immitis. Significantly more gray foxes were seropositive for CPV in the urban zone than in the rural zone. In addition, radio-tracking of gray foxes in the rural zone indicated that all three of the rural CPV-seropositive foxes had traveled into adjoining small towns, whereas only one of the 11 seronegative animals had done so. Significantly more bobcats were seropositive for FCV in the rural zone than in the urban zone. Individual bobcats with positive FCV antibody titers had patterns of movement that intercepted park inholdings where domestic cats lived. Bobcat samples were seronegative for all five of the other viral feline pathogens, with the exception of a FECV-seropositive bobcat. High seroprevalence was detected for B. henselae and T. gondii in both zones. Variation in the seroprevalence for different pathogens might be related to differences in the exposure of bobcats and foxes to domestic animals: in the urban zone, gray foxes were located in residential areas outside the park, whereas bobcats were not. Although for most of the pathogens examined there was no relationship between urbanization and exposure, our results for CPV in foxes and FCV in bobcats indicated that proximity to urban areas or contact with humans can increase the risk of disease exposure for wild carnivore populations. Combining behavioral information from radio-tracking with data on pathogen exposure or disease incidence can provide valuable insights into the ecology of wildlife disease that might be missed with broad-scale, population-level comparisons alone.  相似文献   

8.
The seroprevalence of antibodies to Toxoplasma gondii was investigated in trapped lynx (Lynx canadensis) and bobcats (Lynx rufus) from Québec, Canada. Forty-seven of 106 (44%) lynx and 4 of 10 (40%) bobcats had positive titers for T. gondii (> or = 25) by means of the modified agglutination test incorporating mercaptoethanol and formalin-fixed tachyzoites. Seroprevalence was significantly higher (P < 0.0001) in adult lynx than in juvenile lynx. The presence of antibodies to T. gondii in lynx and bobcats suggests that this organism is widespread in the wild and that exposure to wild felids and game animals from Québec may represent a potential source of infection for humans.  相似文献   

9.
Abstract: Humans introduce many toxicants into the environment, the long-term and indirect effects of which are generally unknown. We investigated exposure to anticoagulant rodenticides and evaluated the association between notoedric mange, an ectoparasitic disease, and anticoagulant exposure in bobcats (Lynx rufus) and mountain lions (Puma concolor) in a fragmented urban landscape in southern California, USA. Beginning in 2002, an epizootic of notoedric mange, a disease previously reported only as isolated cases in wild felids, in 2 years reduced the annual survival rate of bobcats from 0.77 (5-yr average) to 0.28. Anticoagulants were present in 35 of 39 (90%) bobcats we tested, multiple compounds were present in 27 of these 35 (77%), and total toxicant load was positively associated with the use of developed areas by radiocollared animals. Mange-associated mortality in bobcats showed a strong association with anticoagulant exposure, as 19 of 19 (100%) bobcats that died with severe mange were also exposed to the toxicants, and for bobcats with anticoagulant residues >0.05 ppm, the association with mange was highly significant (X2 = 10.36, P = 0.001). We speculate that concomitant elevated levels of rodenticide exposure may have increased the susceptibility of bobcats to advanced mange disease. Bobcats were locally extirpated from some isolated habitat patches and have been slow to recover. In 2004, 2 adult mountain lions died directly from anticoagulant toxicity, and both animals also had infestations of notoedric mange, although not as advanced as in the emaciated bobcats that died with severe disease. Two other mountain lions that died in intraspecific fights also exhibited exposure to 2-4 different anticoagulants. These results show that the effects of secondary poisoning on predators can be widespread, reach even the highest-level carnivores, and have both direct and possibly indirect effects on mortality. Further research is needed to investigate the lethal and sub-lethal effects of anticoagulants and other toxicants on wildlife in terrestrial environments.  相似文献   

10.
Abstract: We assessed the detection and accuracy rates of detection dogs trained to locate scats from free-ranging black bears (Ursus americanus), fishers (Martes pennanti), and bobcats (Lynx rufus). During the summers of 2003-2004, 5 detection teams located 1,565 scats (747 putative black bear, 665 putative fisher, and 153 putative bobcat) at 168 survey sites throughout Vermont, USA. Of 347 scats genetically analyzed for species identification, 179 (51.6%) yielded a positive identification, 131 (37.8%) failed to yield DNA information, and 37 (10.7%) yielded DNA but provided no species confirmation. For 70 survey sites where confirmation of a putative target species' scat was not possible, we assessed the probability that ≤1 of the scats collected at the site was deposited by the target species (probability of correct identification; PID). Based on species confirmations or PID values, we detected bears at 57.1% (96) of sites, fishers at 61.3% (103) of sites, and bobcats at 12.5% (21) of sites. We estimated that the mean probability of detecting the target species (when present) during a single visit to a site was 0.86 for black bears, 0.95 for fishers, and 0.40 for bobcats. The probability of detecting black bears was largely unaffected by site- or visit-specific covariates, but the probability of detecting fishers varied by detection team. We found little or no effect of topographic ruggedness, vegetation density, or local weather (e.g., temp, humidity) on detection probability for fishers or black bears (data were insufficient for bobcat analyses). Detection dogs were highly effective at locating scats from forest carnivores and provided an efficient and accurate method for collecting detection-nondetection data on multiple species.  相似文献   

11.
ABSTRACT Bobcat (Lynx rufus) populations in the Midwestern United States experienced historic declines due to habitat loss and exploitation but have rebounded in recent decades. We investigated natal dispersal of juvenile bobcats from a population in south-central Indiana, USA, from 1999 to 2006. We radiocollared 16 juvenile bobcats (11 M, 5 F) and monitored them for 237–1,014 days (x̄ = 506). One female (20%) and 11 males (100%) dispersed from natal home ranges that averaged 14.6 km2 in size. Most juveniles (70%) initiated dispersal from mid-February through March, late in their first year. Only 5 bobcats (42%) ultimately established a final home range 63 ± 35 km2 in size 13–92 km (x̄ = 44) from their natal range 140 ± 45 days after initiating dispersal. Survival did not differ (P = 0.93) between dispersing (S = 0.73) and philopatric (S = 0.75) individuals, although 4 bobcats (3 M, 1 F) were killed in collisions with vehicles. We found dispersal of bobcats in fragmented landscapes is prolonged and often unsuccessful; the ability of dispersers to locate suitable vacant habitat patches may be vital to the continued growth of bobcat populations recolonizing the agricultural Midwest.  相似文献   

12.
With the exception of human immunodeficiency virus (HIV), which emerged in humans after cross-species transmissions of simian immunodeficiency viruses from nonhuman primates, immunodeficiency viruses of the family Lentiviridae represent species-specific viruses that rarely cross species barriers to infect new hosts. Among the Felidae, numerous immunodeficiency-like lentiviruses have been documented, but only a few cross-species transmissions have been recorded, and these have not been perpetuated in the recipient species. Lentivirus seroprevalence was determined for 79 bobcats (Lynx rufus) and 31 pumas (Puma concolor) from well-defined populations in Southern California. Partial genomic sequences were subsequently obtained from 18 and 12 seropositive bobcats and pumas, respectively. Genotypes were analyzed for phylogenic relatedness and genotypic composition among the study set and archived feline lentivirus sequences. This investigation of feline immunodeficiency virus infection in bobcats and pumas of Southern California provides evidence that cross-species infection has occurred frequently among these animals. The data suggest that transmission has occurred in multiple locations and are most consistent with the spread of the virus from bobcats to pumas. Although the ultimate causes remain unknown, these transmission events may occur as a result of puma predation on bobcats, a situation similar to that which fostered transmission of HIV to humans, and likely represent the emergence of a lentivirus with relaxed barriers to cross-species transmission. This unusual observation provides a valuable opportunity to evaluate the ecological, behavioral, and molecular conditions that favor repeated transmissions and persistence of lentivirus between species.  相似文献   

13.
Ongoing global landscape change resulting from urbanization is increasingly linked to changes in species distributions and community interactions. However, relatively little is known about how urbanization influences competitive interactions among mammalian carnivores, particularly related to wild felids. We evaluated interspecific interactions between medium‐ and large‐sized carnivores across a gradient of urbanization and multiple scales. Specifically, we investigated spatial and temporal interactions of bobcats and pumas by evaluating circadian activity patterns, broad‐scale seasonal interactions, and fine‐scale daily interactions in wildland–urban interface (WUI), exurban residential development, and wildland habitats. Across levels of urbanization, interspecific interactions were evaluated using two‐species and single‐species occupancy models with data from motion‐activated cameras. As predicted, urbanization increased the opportunity for interspecific interactions between wild felids. Although pumas did not exclude bobcats from areas at broad spatial or temporal scales, bobcats responded behaviorally to the presence of pumas at finer scales, but patterns varied across levels of urbanization. In wildland habitat, bobcats avoided using areas for short temporal periods after a puma visited an area. In contrast, bobcats did not appear to avoid areas that pumas recently visited in landscapes influenced by urbanization (exurban development and WUI habitat). In addition, overlap in circadian activity patterns between bobcats and pumas increased in exurban development compared to wildland habitat. Across study areas, bobcats used sites less frequently as the number of puma photographs increased at a site. Overall, bobcats appear to shape their behavior at fine spatial and temporal scales to reduce encounters with pumas, but residential development can potentially alter these strategies and increase interaction opportunities. We explore three hypotheses to explain our results of how urbanization affected interspecific interactions that consider activity patterns, landscape configuration, and animal scent marking. Altered competitive interactions between animals in urbanized landscapes could potentially increase aggressive encounters and the frequency of disease transmission.  相似文献   

14.
Space use and diets of sympatric bobcats Lynx rufus and pumas Puma concolor were compared using sign surveys and scat analysis during 1997–2002 in south-eastern Arizona, USA. Bobcats appeared to use grassland, scrub, riparian and woodland habitats equally, but pumas had higher activity in riparian and woodland habitats. There was little evidence that bobcats avoided pumas in space use. Bobcats ate primarily rodents (33% of items in scats), lagomorphs (32%) and ungulates (16%), whereas pumas ate primarily ungulates (69%) and carnivores (21%). Pumas had a narrower dietary niche breadth than bobcats, and puma diet overlapped bobcat diet by 56%, suggesting that pumas may be more vulnerable to changes in prey density than bobcats. Pumas also killed and consumed bobcats, indicating that interference competition may be manifesting through intraguild predation.  相似文献   

15.
Nutrient digestibility has not been well characterized in exotic felids. The objective of this experiment was to evaluate differences in nutrient digestibility and fecal characteristics in five large exotic captive felid species, including bobcats, jaguars, cheetahs, Indochinese tigers, and Siberian tigers. All animals were individually housed and adapted to a beef‐based raw diet (Nebraska Brand® Special Beef Feline, North Platte, NE) for 16 d. Total fecal collections were conducted from days 17 to 20. Fecal samples were weighed and scored on collection. Diet and fecal samples were evaluated for dry matter, organic matter, protein, fat, and energy to determine total tract digestibility. Fresh fecal samples were collected to determine fecal pH, ammonia, phenol, indole, short‐chain fatty acid, and branched‐chain fatty acid concentrations. Fecal scores were greater (P<0.01) in Indochinese tigers when compared with all other species, and cheetahs had greater (P<0.01) fecal scores than jaguars and bobcats. Fat digestibility was greater (P<0.01) in Siberian tigers, Indochinese tigers, and bobcats (96%) compared with cheetahs and jaguars (94%). Digestible energy was greater (P<0.05) in bobcats and Indochinese tigers at 93.5 and 92.9%, respectively, compared with cheetahs and jaguars, 91.6%. Fecal pH was greater (P<0.01) in bobcats compared with all other species evaluated. Indole concentrations were greater (P<0.05) in cheetahs and jaguars compared with bobcats and Indochinese tigers. Fecal ammonia concentrations were increased (P<0.05) in cheetahs compared with all other species. The beef‐based raw diet was highly digestible; however, differences in fat and digestible energy suggest that species should be considered when determining caloric needs of exotic felids. Zoo Biol 27:126–136, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

16.
Schizogonous tissue stages of Cytauxzoon felis (Apicomplexa: Theileridae) were not observed by microscopic evaluation of impression smears of liver, spleen, lung and lymph nodes in 10 bobcats (Lynx rufus) from Oklahoma with naturally occurring piroplasm infections. Schizogonous stages were observed in similar tissues from experimentally-infected bobcats at 11 days postexposure to infected Dermacentor variabilis, but not at 30 days following tick feeding. The schizogonous cycle of this parasite appears to be short, although the bobcat appears to be a long-term carrier.  相似文献   

17.
Considerable uncertainty often exists in estimates of demographic parameters based on data collected from harvested furbearer species. We used molecular genetic techniques to estimate rates of error in 2 methods of sex determination of harvested bobcats (Lynx rufus): manual examination of the carcass (field sex) and laboratory-based maximum canine root area (MRA sex). Error rates were high for both sexing techniques, and were associated with age and an age–sex interaction for the field and MRA sexing methods, respectively. These findings do not support the use of the field methods for identifying sex of harvested bobcats. The MRA method may be effective for determining sex of older bobcats but is limited by considerable overlap between sexes in juveniles and yearlings. If critical demographic parameters are estimated from harvest data, efforts should be made to identify and reduce rates of error before data are used to assess population status. © 2011 The Wildlife Society.  相似文献   

18.
Abstract Understanding interactions among bobcats (Lynx rufus) may lend insight into less understood life history traits of the bobcat and improve management of the species. Moreover, data from manipulative experiments pertaining to bobcat ecology are largely absent from the scientific literature. Therefore, we investigated bobcat spatial organization and habitat use after an experimental population reduction on an 11,735-ha study site in southwestern Georgia, USA. In response to an approximate 50% population reduction, male bobcats shifted their space use (26.4 ± 1.7% more shift relative to baseline) more (F1,3 = 138.08, P=0.001) than males where no bobcat removal occurred (28.1 ± 5.5% less shift relative to baseline). Dispersion of radio locations for all female bobcats increased following the population reduction; however, females that were exposed to the removal of a potentially interacting male remained more (F1,14 = 6.78, P = 0.021) static (increase in dispersion = 7.8 ± 7.3%) than females that were not exposed to removed males (increase in dispersion 41.2 ± 11.1%). Male bobcats likely shifted their central tendency to increase breeding opportunities, whereas the difference in dispersion of female radio locations may be the result of decreased intraspecific competition. Alternatively, reduced dispersion of females following harvest of neighboring males may increase the likelihood that remaining males will interact with females for breeding purposes. Neither habitat use nor habitat selection differed as a function of removal, suggesting that density-dependent habitat selection was not occurring on our study site. Although it is generally accepted that male bobcats use space to increase breeding opportunities, our study suggests that male bobcats may also influence space use of females, but in counterintuitive ways. Because bobcat movements are altered by harvest of neighbors, we suggest that inferring habitat quality for bobcats based on their space use patterns should be avoided unless researchers incorporate knowledge of both short- and long-term population perturbations.  相似文献   

19.
We used scat analysis and radiotelemetry to characterize use of foods and habitats by sympatric bobcats and coyotes, and evaluated these in the context of spatial and temporal relationships to assess the potential for, and evidence of, interspecific competition. Bobcats and coyotes exhibited broad and overlapping diets. However, diets of the two predators differed in the relative contributions of small and large prey, with bobcats consuming relatively more rodent and lagomorph biomass and coyotes consuming relatively more ungulate biomass. Consumption among rodent prey species was highly correlated between bobcats and coyotes, indicating no evidence of prey partitioning within this group. Habitat selection by the two predators differed slightly at the landscape scale but not within home ranges. Bobcats and coyotes occupied small, overlapping home ranges, such that the likelihood of interspecific encounters (direct or indirect) was high. Bobcats displayed slight avoidance of overlapping coyote core areas during coyote reproductive seasons (winter and spring), when coyotes are typically most territorial (toward conspecifics), but displayed slight attraction during times of year when coyotes were not engaged in reproductive activities. Relative to coyotes, which were strongly nocturnal, diel activity patterns of bobcats were more diurnal and variable. However, activity patterns were not inversely correlated. Overall, these predators appeared to use resources independently and we found little evidence of negative interactions. Differences in resource use by bobcats and coyotes appeared to relate to fundamental niche differences as opposed to competition-related resource partitioning.  相似文献   

20.
ABSTRACT In Quebec, Canada, harvest of bobcats (Lynx rufus) started to decline in 1985 and by 1991, harvest seasons were closed due to concerns of a perceived population decline. Since the closing of harvest season in 1991, the average temperature has increased, snow quantity has decreased, and important changes in agriculture and forest management have occurred. In light of changing conditions, the situation of Quebec bobcats needed reassessment. Thus, we analyzed harvest data to clarify the current status of bobcat populations in Quebec. From 1980 to 1991, bobcat harvest in Quebec was strongly correlated with bobcat harvest in Maine (USA), Nova Scotia (Canada), Ontario (Canada), and Vermont (USA). Extrapolations of harvest in Quebec relative to harvest in Maine, Ontario, Vermont, and Nova Scotia suggested an increase in number of bobcats after 1991. Mass of male and female bobcats before 1991 was less than mass of animals captured after 1991. Percentage of juveniles in the reported harvest before 1991 was higher than after 1991. However, percentage of males and litter sizes in the harvest did not differ before and after 1991. The geographic distribution of bobcats captured has gradually expanded after the closure of the harvest season. Our findings suggest that bobcat populations in Quebec have recovered from the 1985–1991 decline, and that the harvest season for this species could resume. This study also illustrates how managers can rely on data from neighboring jurisdiction to manage species when local harvest data is unavailable.  相似文献   

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