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The number of ground‐nesting ducks in the marshes of Great Salt Lake (GSL), Utah has drastically decreased in the past few decades. One potential cause for this decline is the increase in climate extremes caused by global warming. From 2019 through 2023, GSL marshes experienced 1 year of historic spring rainfall (2019), 2 years of historic droughts (2021 and 2022), and 1 year of record snowfall (2023). We used this time period to test the hypothesis that climate extremes impact both the number of duck nests and their fate (i.e., successful, depredated, or abandoned). We counted 563 nests of cinnamon teal (Spatula cyanoptera), 168 mallards (Anas platyrhynchos), and 220 gadwalls (Mareca strepera). Nest numbers varied among years and were positively correlated with the amount of spring rainfall (April and May). Clutch sizes differed among years and were lowest during the drought years. Raccoons (Procyon lotor) and striped skunks (Mephitis mephitis) were the major predators of nests. The percentage of all duck nests that were depredated varied among years and increased from 40% and 46% during the 2 wet years to 75% and 90% during the 2 drought years. The percentage of nests that were successful varied among years and were highest during the wet years. The yearly percentage of successful nests was negatively correlated with the abundance of all predators and positively correlated with snowfall because few skunks and raccoons survived the winter of 2023 with its heavy snowfall. Daily survival rates (x¯$$ \overline{x} $$ = 0.93), were similar among duck species, but varied among years; DSRs were lowest during the drought years (0.86 and 0.92) and highest during the wet years (0.96 for both years). Our results suggest that climate extremes will have an adverse impact on both the number of duck nests and the percentage of them that are successful. [ABSTRACT FROM AUTHOR]

Disease caused by the archetypical amdoparvovirus (APV), Aleutian mink disease virus (AMDV), has been well studied, but APV infections in other carnivores are poorly understood. Skunk amdoparvovirus (SKAV), one of a handful of newly discovered APVs, is apparently species-specific in striped skunks (Mephitis mephitis) and has a high prevalence across North America. We have evaluated the infection status and viral tissue distribution in a cohort of 26 free-ranging California skunks from a single rehabilitation facility who were euthanized due to poor prognosis for recovery from neurologic disease. SKAV was detected in the majority of this cohort, and virus was associated with a spectrum of lesions including tubulointerstitial nephritis, meningoencephalitis, myocarditis, and arteritis. Affected tissue and patterns of inflammation were partially overlapping with those of AMDV infection but were notably distinct in the kidney.

Conflicts between humans and mesopredators are frequent and widespread. Over the last decades, conflicts have led to the development and application of different mitigation methods to diminish the costs and damage caused by such conflicts. We conducted a systematic literature search and meta‐analysis to assess the influence of different mitigation methods on 3 common nuisance species: raccoons (Procyon lotor), red foxes (Vulpes vulpes), and striped skunks (Mephitis mephitis). A majority of the studies, from 1963‒2022, were conducted in North America, followed by Australia and Europe. The predation of wildlife species of conservation concern by nuisance species is the main reported source of conflict in the published literature. Lethal control is the most commonly tested method and is generally effective at reducing conflicts based on the calculated effect size. Barriers have mixed effects, with electric fences and nest exclosures both being effective, whereas conventional fences seem to be less effective. Repellents mimicking predators (e.g., guard animal, predator smell) are also effective. Conditioned taste aversion is a promising approach, but no precise product or chemical has proven to be effective. Many interventions suffered from a lack of validation through experimental approach. Research on human–mesopredator conflict mitigation would benefit from repeated studies using the same methods in similar contexts, thus reducing heterogeneity in the results, and by testing new and innovative methods. [ABSTRACT FROM AUTHOR]

Context. Anthropogenic landscape changes have substantial effects on biodiversity and animal populations worldwide. However, anthropogenic landscape change can take a variety of forms, and its effects on wildlife species can vary by landscape context and scale. It is therefore critical that studies of the effects of anthropogenic landscape change on wildlife consider landscape context and model effects of landscape change at multiple scales. Mesopredators serve as an excellent case study of scale-dependent and even contradictory effects of anthropogenic landscape change, because mesopredator populations can respond both positively and negatively to landscape change depending on its form (e.g. agricultural production, urbanisation) and scale. Aims. The aim of this study was to model relationships between multiple aspects of anthropogenic landscape change, including agricultural production and the proliferation of non-native shrubs, and relative abundance of three mesopredator species: Virginia opossum (Didelphis virginiana), striped skunk (Mephitis mephitis), and raccoon (Procyon lotor). Methods. We summarised landscape variables at two scales and built both single-scale and multi-scale models linking relative abundance of mesopredators to landscape variables. Key results. We found that relative abundance of all three species was most related to either the transition from natural areas to agricultural areas (brown-to-green gradient) or the likelihood of presence of non-native shrubs. We also found that responses to anthropogenic landscape change varied by spatial scale; for instance, skunks and raccoons had higher relative abundance in parts of Illinois with more forest cover and agriculture, respectively, but avoided more highly forested and agricultural areas, respectively, at smaller scales. Conclusions. Mesopredator responses to landscape change were highly variable and scale-dependent, but were generally related to transitions from forest to agriculture or the presence of non-native shrubs. Implications. Our study demonstrates the need to model effects of anthropogenic landscape change at multiple scales, given the differing resultsthat can be achieved when landscape variables are measured at multiple scales. [ABSTRACT FROM AUTHOR]

Skunk amdoparvovirus (Carnivore amdoparvovirus 4, SKAV) is closely related to Aleutian mink disease virus (AMDV) and circulates primarily in striped skunks (Mephitis mephitis) in North America. SKAV poses a threat to mustelid species due to reported isolated infections of captive American mink (Neovison vison) in British Columbia, Canada. We detected SKAV in a captive striped skunk in a German zoo by metagenomic sequencing. The pathological findings are dominated by lymphoplasmacellular inflammation and reveal similarities to its relative Carnivore amdoparvovirus 1, the causative agent of Aleutian mink disease. Phylogenetic analysis of the whole genome demonstrated 94.80% nucleotide sequence identity to a sequence from Ontario, Canada. This study is the first case description of a SKAV infection outside of North America. [ABSTRACT FROM AUTHOR]

Urban coyotes are commonly exposed to rodenticides used to control non-native commensal rodents, but these rodents are rare in published accounts of their diets. An alternative source of rodenticide exposure is through the consumption of mesocarnivores that have themselves eaten either toxic bait directly or poisoned rodents or invertebrates. Carcasses of 311 nuisance and road-killed coyotes from suburban and urban areas of southern California were collected from 2016-2018. Stomachs were dissected and prey items were identified visually. Stomach contents containing tissue from suspected mammalian prey (N = 178) were homogenized and DNA was extracted. Genus-specific primers (123-366 bp) were designed for Virginia opossums, raccoons, and striped skunks, regionally common species that are known to be consumed by coyotes. PCR was performed for each primer pair, and presence of PCR products of particular amplicon lengths were determined by gel electrophoresis. Coyote stomachs containing a PCR product of the appropriate size were considered to contain that prey item. Land use data were used to assess landscape factors that are associated with the consumption of mesocarnivores. Combining both techniques, mesocarnivores were detected at low frequencies: opossums (8%) were more common than raccoons (2%) and skunks (2%). Some 72% of meso-carnivores present in stomachs were detected by molecular methods, while 66% were identified by morphological methods. Opossums were associated with increased development and anthropogenic land use, while skunks were associated with large natural areas, and raccoons used all habitat types. The extent to which mesocarnivores themselves eat poisoned prey remains unknown, although they may be a potential source of exposure for coyotes. Additionally, landscape factors do not appear to be related to raccoon consumption but may influence presence, and therefore consumption, of skunks and opossums.

Babesia species are intraerythrocytic protozoan parasites that infect a variety of hosts. The goal of this study was to evaluate the piroplasm species present in skunks in various states in the United States and determine whether there was any geographic variation. Spleen, whole blood, or blood on filter paper were received from Pennsylvania, Kentucky, North Carolina, South Carolina, Georgia, Missouri, Louisiana, Texas, Kansas, and California, and were tested for Babesia sp. We tested four species of skunks including striped skunk (Mephitis mephitis, n = 72), eastern spotted skunk (Spilogale putorius, n = 28), western spotted skunk (Spilogale gracilis, n = 15), and hog-nosed skunk (Conepatus leuconotus, n = 11). A PCR assay targeting the 18S rRNA region and cox1 region were used to determine if skunks were infected with piroplasms and for phylogenetic analyses. A total of 48.4% (61/126) of skunks tested positive for a Babesia species. Both the 18S and cox1 analysis supported a skunk-specific Babesia microti-like sp. of carnivores as well as a species in the B. microti complex that is phylogenetically unique from both B. microti of humans and the B. microti-like sp. of carnivores. In the 18S analysis, there was a third species of Babesia in hog-nosed skunks in the western piroplasm group. This study shows that at least three species of piroplasms occur in skunk species in the United States and further highlights the importance of phylogenetic analyses and the use of multiple gene targets when studying piroplasms.

The effectiveness of tiletamine-zolazepam (1.7 mg/kg) plus medetomidine (0.07 mg/kg; TZM) as an immobilizing combination in raccoons (Procyon lotor; n=43) and striped skunks (Mephitis mephitis; n=7) was evaluated during October 2019. Mean (±SD) induction time for raccoons was 15.0±6.6 min. First signs of recovery (head up) occurred 12.9±6.0 min after receiving atipamezole reversal (0.35 mg/kg) and animals were standing in 30.3±16.1 min. Mean induction time for skunks was 11.7±5.8 min. Following reversal, skunks first raised their heads in 6.7±4.3 min and stood in 17.1±12.9 min. Recovery in skunks and female raccoons was not related to length of time immobilized, but male raccoons that were immobilized for longer periods of time stood faster after reversal. Raccoon heart rate (HR) remained steady during immobilization, but respiration rate (RR) and rectal temperature (RT) declined. The HR and RR were similar among males and females, but RT of male raccoons were, on average, 0.5 C higher than those of females, and rate of temperature decline was slower for males. The HR, RR, and RT of skunks declined during immobilization. Although induction times for both raccoons and skunks were longer than expected, induction and recovery were smooth, side effects were few, analgesia was adequate for nonsurgical procedures, and reversal reduced time in captivity. [ABSTRACT FROM AUTHOR]

The oil produced by the anal glands of the striped skunk is known to be a strong deterrent to potential predators. However, it is also a common ingredient in many trap lures, especially those for carnivores such as the coyote. This paradoxical nature of skunk oil being both attractive and aversive has yet to be investigated, leaving a gap in the understanding of how predators of skunks respond to visual and olfactory information. In this project, camera traps with baited skunk models with either black-andwhite or brown pelage were deployed in natural areas around Southern California in order to study the effects of skunk oil and pelt coloration on predator behavior. Our study found scented models were less likely to be visited, indicating an avoidance of the oil and its scent.

Wild animals have been implicated as the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but it is largely unknown how the virus affects most wildlife species and if wildlife could ultimately serve as a reservoir for maintaining the virus outside the human population. We show that several common peridomestic species, including deer mice, bushy-tailed woodrats, and striped skunks, are susceptible to infection and can shed the virus in respiratory secretions. In contrast, we demonstrate that cottontail rabbits, fox squirrels, Wyoming ground squirrels, black-tailed prairie dogs, house mice, and racoons are not susceptible to SARS-CoV-2 infection. Our results expand the knowledge base of susceptible species and provide evidence that human-wildlife interactions could result in continued transmission of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Scavenging is a known behavior of striped skunks (Mephitis mephitis), though it is rarely documented. Striped skunks were observed and documented scavenging nine human donors at the Forensic Investigation Research Station (FIRS) in Whitewater, Colorado from October 2017 through September 2019. Human remains are placed on the surface, outdoors, in a fenced area, and monitored daily through notes, photographs, and multiple systems for scoring decomposition. Motion‐activated game cameras are strategically positioned to monitor potential scavenger activity within the facility. When scavenging occurred, game camera images were temporally correlated to daily photographs and notes to confirm the source of observed defects. Striped skunks at the FIRS scavenged the soft tissue of the arms, legs, genitals, and torso. Game camera images documented skunks digging, climbing on top of remains, repositioning limbs, and using their paws to manipulate tissue. These activities impacted soft tissue, bone, and the surrounding environment. Scavenging patterns varied seasonally, with higher frequency and lower selectivity in the winter. Striped skunks are common throughout most of North America and are likely to scavenge human remains when available. Understanding patterns and behaviors of specific scavengers can help investigators accurately interpret defects found on and around human remains. [ABSTRACT FROM AUTHOR]

Rabies is a fatal viral zoonosis that is transmitted by bite contact with saliva of an infected animal. In the U.S., human deaths are rare, but each year over 5,000 rabid animals are reported and over 90% of cases are from wildlife. Multiple species of carnivores and bats are the primary sylvatic reservoirs in the U.S., and several variants circulate independently among these two taxonomic orders. Rabies prevention efforts led by USDA APHIS Wildlife Services using live recombinant vaccine baiting began in 1995 and currently target raccoons and canids, but the territory of the south-central skunk rabies virus variant has been expanding in recent years, leading to incursions into areas previously free of carnivore rabies. Colorado has been one such area, where multiple species of bats were the main rabies reservoir prior to 2007. By 2012, the number of rabid striped skunks exceeded rabid bats in Colorado. Larimer County and Weld County, in Northern Colorado, both witnessed skunk rabies epizootics starting in 2012 that have continued through 2013. Despite spillover events into raccoons, red foxes, companion animals, and livestock during 2012 and 2013, no other host species appears to support independent circulation of the south-central skunk variant in Northern Colorado. Virus isolation from salivary glands of rabid animals will help to quantify the likelihood for secondary transmission from spillover hosts and guide intervention strategies targeting wildlife. We describe the spatiotemporal pattern of the epizootic and predict likely areas of spread along the Front Range of Northern Colorado.

Targeted surveillance for raccoon rabies virus was conducted between February and May 2017, near Waweig, New Brunswick, Canada, in response to detection of a rabid striped skunk (Mephitis mephitis) on 8 February 2017. A total of six skunks, 11 raccoons (Procyon lotor), and two porcupines (Erethizon dorsatum) were live-trapped, euthanized, and tested for rabies virus antigens using the direct rapid immunohistochemical test. Of these, only two skunks tested positive for rabies. All three rabid skunks came from the same location, an abandoned barn used as a denning site. Four of five skunks removed from this barn were males. Feeding, aggression, extreme response to noise and light stimuli, and exposure to porcupine quills were observed in two rabid skunks. No additional cases of rabies in wildlife were detected in the area since 8 March 2017. A targeted surveillance approach that removed potentially infected wildlife followed by localized oral rabies vaccine distribution was implemented in this locality. [ABSTRACT FROM AUTHOR]

Communication behaviors play a critical role in both an individual's fitness as well as the viability of populations. Solitary animals use chemical communication (i.e., scent marking) to locate mates and defend their territory to increase their own fitness. Previous research has suggested that striped skunks (Mephitis mephitis) do not perform scent-marking behaviors, despite being best known for using odor as chemical defense. We used video camera traps to document behaviors exhibited by striped skunks at a remote site in coastal California between January 2012 and April 2015. Our camera traps captured a total of 71 visits by striped skunks, the majority of which (73%) included a striped skunk exhibiting scent-marking behaviors. Overall, we documented 8 different scent-marking behaviors. The most frequent behaviors we documented were cheek rubbing (45.1%), investigating (40.8%), and claw marking (35.2%). The behaviors exhibited for the longest durations on average were grooming ( x ¯ = 34. 4 s) and investigating ( x ¯ = 21.2 s). Although previous research suggested that striped skunks do not scent mark, we documented that at least some populations do and our findings suggest that certain sites are used for communication via scent marking. Our study further highlights how camera traps allow researchers to discover previously undocumented animal behaviors. [ABSTRACT FROM AUTHOR]

The most important reservoir of wildlife rabies on the American Great Plains is the striped skunk. A rabid striped skunk taken in August 1988 near Deaver, WY became the index case for a subsequent epizootic in a previously skunk rabies free area. In 1989, more rabid skunks occurred and the epizootic was moving throughout Sage Creek and in later years (1990-1993) through the entire Shoshone River basin. Federal, state, and local officials cooperated in a rabies program with the goal of addressing the health and safety of the region’s citizens, domestic animals, and livestock. Three areas of focus in the program were: 1) immunization of pets and livestock, 2) public education, and 3) skunk population monitoring and control. Rabies immunizations were re-emphasized by the local veterinarians and public health officials for pets to decrease potential rabies spillover to other species. Public education emphasized the dangers of rabies and the behavior of rabid animals using local news media and assemblies at area schools. This paper provides a synoptic overview of the third component – skunk population monitoring and control provided by USDA/APHIS’s Wyoming Wildlife Services (WS). WS provided trapping expertise starting in 1990 with rabid specimens identified by the Wyoming State Veterinary Laboratory. Starting in 1990, WS’s National Wildlife Research Center provided data analysis of rabid locations for the entire epizootic (i.e., 1988-1993). These analyses demonstrated the epizootic’s movements through the novel first use of a Geographic Information System that merged a wildlife disease (i.e., rabies) case/capture locations and dates with additional GIS data layers including hydrology, human population density, and land use. The epizootic ended in 1994 with striped skunks, bats, cats, and one horse affected. Studying this epizootic should benefit officials in planning future surveillance and/or depopulation programs. This study demonstrated the need for a skunk rabies vaccine and effective delivery system, and if the latter had been available maybe this epizootic would have been more limited in its scope and duration.

A Live Trap Loaning Program has evolved to address urban wildlife problems in Reno, Nevada. The program, operated by USDA Wildlife Services, has responded to the public’s need to address urban wildlife problems in the absence of an active Wildlife Services specialist in this urban area. The species for which most of the live traps (cage or enclosed) have been requested, since the program’s initiation in FY 1992, are California ground squirrels, raccoons, and striped skunks. We discuss information transfer and educational components of this program, which convey to the public information on the biology of target species, proper handling of non-target catches, handouts, and options available for resolving their wildlife problems.

ABSTRACT We tested whether striped skunks (Mephitis mephitis) in Flagstaff, Arizona, USA, could be recognized based on variation in pelage patterns and whether camera position influenced that outcome. We presented 11 volunteers with 2 sets of 24 photographs taken between 1 January and 15 February 2015, one with animals photographed from the side, the other from above. Each set of 24 photographs included 9 pairs, with each pair representing 2 different images of the same animal. Volunteers scored twice as many correct matches and 4‐fold fewer false matches when photographs were taken from above. Regardless of camera position, the total number of unique skunks in each set was underestimated (83% of total from above, 75% from side), likely because some skunks had very similar pelage patterns. Our results indicate that variation in nose stripe, back stripe, dorsal and ventral tail pattern, and shape of tail can be used to recognize individual striped skunks but similarity in those characteristics among some individuals may cause total number of unique individuals to be underestimated regardless of camera orientation. © 2017 The Wildlife Society.

The role of free‐ranging wildlife in the epidemiology of enteropathogens causing clinical illness in humans and domestic animals is unclear. Salmonella enterica and anti‐microbial resistant bacteria have been detected in the faeces of raccoons (Procyon lotor), but little is known about the carriage of these bacteria in other sympatric meso‐mammals. Our objectives were to: (a) report the prevalence of Salmonella and associated anti‐microbial resistance, Campylobacter spp, Clostridium difficile, and anti‐microbial resistant Escherichia coli in the faeces of striped skunks (Mephitis mephitis) and Virginia opossums (Didelphis virginiana) in southern Ontario; and (b) compare the prevalence of these bacteria in the faeces of these meso‐mammal hosts with raccoons from a previously reported study. Faecal swabs were collected from striped skunks and Virginia opossums on five swine farms and five conservation areas from 2011 to 2013. Salmonella was detected in 41% (9/22) and 5% (5/95) of faecal swabs from Virginia opossums and striped skunks, respectively. None of the Salmonella serovars carried resistance to anti‐microbials. The prevalence of Campylobacter spp., C. difficile, and anti‐microbial resistant E. coli ranged from 6% to 22% in striped skunk and Virginia opossums. Using exact logistic regression, Salmonella was significantly more likely to be detected in faecal swabs of Virginia opossums than skunks and significantly less likely in faecal swabs from skunks than raccoons from a previously reported study. In addition, Campylobacter spp. was significantly more likely to be detected in raccoons than opossums. Salmonella Give was detected in 8/9 (89%) of Salmonella‐positive Virginia opossum faecal swabs. Our results suggest that striped skunks and Virginia opossums have the potential to carry pathogenic enteric bacteria in their faeces. The high prevalence of Salmonella Give in Virginia opossum faecal swabs in this study as well as its common occurrence in other Virginia opossum studies throughout North America suggests Virginia opossums may be reservoirs of this serovar. [ABSTRACT FROM AUTHOR]

Few studies have investigated the ecology of urban striped skunks (Mephitis mephitis) despite their role as a primary rabies vector species paired with an ability to thrive in these landscapes. Information on home range, nightly movements, and habitat selection, is important for rabies management planning regarding the placement of oral rabies vaccine (ORV) baits and for management of skunk populations more generally. Our aim was to obtain baseline ecological information with an emphasis on spatial ecology of urban striped skunks in the Northern Great Plains region that is lacking in the literature. We used radio telemetry to track 22 (4 M, 18 F) skunks during September 2016 to November 2016 and March 2017 to November 2017. Size of home range using kernel density estimation with smoothing by least squares cross validation identified that male skunks ( x ¯ = 4.36 km2, SE ± 0.79) had larger home ranges than females ( x ¯ = 1.79 km2, SE ± 0.24). Female skunk home ranges varied by season with the largest home ranges detected during summer 2017. We found no evidence that use-availability was associated with habitat type or season among female skunks. Female skunks were more likely to be found closer to water; however, we found no association of use with road characteristics and geographic location within the study area. Targeting ORV efforts in areas near water may be warranted, but considering differences in habitat selection for skunk studies in urban areas, we caution that ORV baiting programs may not be one-size-fits-all, and a framework for effective bait placement would benefit from studies specific to the management area of interest. [ABSTRACT FROM AUTHOR]

Twenty-five Conservation Reserve Program (CRP) contract holders in Riley County, Kansas were surveyed by telephone to assess their perceptions of wildlife damage relative to CRP plantings. Sixty-four percent experienced wildlife damage on their farm or ranch. Respondents felt that five species causing damage on their farm or ranch had become more common due to enrollment of lands in the CRP. White-tailed deer (Odocoileus virginianus) accounted for 64.3% of these observations, followed by wild turkey (Meleagris gallopavo), eastern cottontail (Sylvilagus floridanus), striped skunk (Mephitis mephitis), and Virginia opossum (Didelphis virginiana), which accounted for 14.3%, 7.1%, 7.1 %, and 7.1% of the damage observations, respectively. Only 12.5% of respondents attempted to control wildlife damage, and none felt that wildlife damage was severe enough to preclude future enrollment in programs such as the CRP. Most respondents allowed hunting or trapping by non-family members on their CRP lands (68.8%), but none felt that increased hunting or trapping would reduce the amount of wildlife damage they experienced. All respondents felt that the benefits of the CRP exceeded costs associated with wildlife damage and that the program was highly beneficial overall.

ABSTRACT: The Flint Hills ecoregion is the largest remaining tract of native tallgrass prairie in North America. Contemporary landscape change (e.g., urbanization, agricultural production) in this region is likely affecting native biodiversity; however, we have a limited understanding of how these changes might affect carnivores. We used camera traps distributed across urban‐rural land‐use gradients, and multiseason occupancy models, to investigate the influence of landscape structure and composition on habitat occupancy dynamics of 3 native carnivores (coyote [Canis latrans]; bobcat [Lynx rufus]; and striped skunk [Mephitis mephitis]) and 1 nonnative carnivore (domestic cat) in the Flint Hills, Kansas, USA, during 2016–2017. Additionally, we assessed the potential for coyotes, the apex predator in the Flint Hills, to mediate habitat occupancy of domestic cats. We also examined the relative influence of landscape factors on native carnivore species richness and diversity. As predicted, coyotes were less likely to occupy and colonize sites, and more likely to leave sites, surrounded by urban landcover. Habitat occupancy by bobcats was positively associated with forest landcover and edge densities; however, bobcats seemed insensitive to urban landcover. Additionally, bobcats were more likely to colonize sites with more grassland and row‐crop agriculture landcover. Surprisingly, striped skunk occupancy and colonization rates at sites were negatively related to urban landcover. As expected, domestic cats were more likely to occur at and colonize sites with increased urban landcover and less likely at sites with high coyote occupancy probabilities. Carnivore species diversity and richness were negatively related to the urban landcover. Our results suggest that urban landcover may limit the spatial distributions of some native carnivores in the Flint Hills and contribute to reduced carnivore diversity. Moreover, urban landcover in the Flint Hills may provide domestic cats with refugia from intraguild pressures by coyotes. Our results provide wildlife managers with insights into how contemporary landscape change in this imperiled ecosystem may affect biodiversity conservation and maintenance. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Prey species defend themselves behaviourally and morphologically, and often use varied antipredator strategies against dissimilar predator types (i.e. terrestrial versus aerial). Striped skunks, Mephitis mephitis , spray noxious secretions at predators and advertise this danger with deterrent behaviours and black-and-white aposematic coloration. Evidence suggests skunks are effective at deterring terrestrial mammalian predators but are vulnerable to aerial predators; how skunks assess the risk posed by different predator types, however, has not been examined empirically. We recorded the behavioural responses of skunks to audio playbacks of coyotes, Canis latrans , and great horned owls, Bubo virginianus (the primary terrestrial and aerial predators of skunks, respectively), and peregrine falcons, Falco peregrinus , and white noise as controls. Skunks ran away more often from vocalizations of their main predators, great horned owls and coyotes, than from diurnal falcon vocalizations or white noise recordings. Skunks also tended to run away sooner in response to owl vocalizations than falcon or coyote vocalizations. Finally, subjects tended to engage in vigilance more frequently in response to owl vocalizations than in response to coyote vocalizations, which together with other results suggest that skunks may perceive owls as more threatening relative to coyotes. This study elucidates how a well-defended mammal can determine which perceived threat is the riskiest and alter its behaviour when its main defence strategy may not be successful against all predator types. Highlights • Skunk defences were more effective against mammalian predators than avian predators. • Skunks fled sooner and more often from great horned owl calls than from coyote calls. • Owls may be perceived as more threatening than coyotes. • Skunk responses to a predator varies based on the predator's relative threat. [ABSTRACT FROM AUTHOR]

Small-to-medium sized mammals and large animals are lucrative sources of blood meals for ixodid ticks that transmit life-threatening tick-borne flaviviruses (TBFVs). TBFVs have been isolated from various organs obtained from wild-caught Myodes and Apodemus species in Europe and Asia. Thus, these rodents are well-established reservoirs of TBFVs. Wild-caught Peromyscus species have demonstrated seropositivity against Powassan virus, the only TBFV known to circulate in North America, suggesting that they may play an important role in the biology of the virus in this geographic region. However, virus isolation from Peromyscus species is yet to be demonstrated. Wild-caught medium-sized mammals, such as woodchucks (Marmota monax) and skunks (Mephitis mephitis) have also demonstrated seropositivity against POWV, and virus was isolated from apparently healthy animals. Despite the well-established knowledge that small-to-medium sized animals are TBFV reservoirs, specific molecular biology addressing host-pathogen interactions remains poorly understood. Elucidating these interactions will be critical for gaining insight into the mechanism(s) of viral pathogenesis and/or resistance. [ABSTRACT FROM AUTHOR]

Background: Prevention and control of wildlife disease invasions relies on the ability to predict spatio-temporal dynamics and understand the role of factors driving spread rates, such as seasonality and transmission distance. Passive disease surveillance (i.e., case reports by public) is a common method of monitoring emergence of wildlife diseases, but can be challenging to interpret due to spatial biases and limitations in data quantity and quality. Methodology/Principal findings: We obtained passive rabies surveillance data from dead striped skunks (Mephitis mephitis) in an epizootic in northern Colorado, USA. We developed a dynamic patch-occupancy model which predicts spatio-temporal spreading while accounting for heterogeneous sampling. We estimated the distance travelled per transmission event, direction of invasion, rate of spatial spread, and effects of infection density and season. We also estimated mean transmission distance and rates of spatial spread using a phylogeographic approach on a subsample of viral sequences from the same epizootic. Both the occupancy and phylogeographic approaches predicted similar rates of spatio-temporal spread. Estimated mean transmission distances were 2.3 km (95% Highest Posterior Density (HPD95): 0.02, 11.9; phylogeographic) and 3.9 km (95% credible intervals (CI95): 1.4, 11.3; occupancy). Estimated rates of spatial spread in km/year were: 29.8 (HPD95: 20.8, 39.8; phylogeographic, branch velocity, homogenous model), 22.6 (HPD95: 15.3, 29.7; phylogeographic, diffusion rate, homogenous model) and 21.1 (CI95: 16.7, 25.5; occupancy). Initial colonization probability was twice as high in spring relative to fall. Conclusions/Significance: Skunk-to-skunk transmission was primarily local (< 4 km) suggesting that if interventions were needed, they could be applied at the wave front. Slower viral invasions of skunk rabies in western USA compared to a similar epizootic in raccoons in the eastern USA implies host species or landscape factors underlie the dynamics of rabies invasions. Our framework provides a straightforward method for estimating rates of spatial spread of wildlife diseases. [ABSTRACT FROM AUTHOR]

Tumors are infrequently reported in skunks, with only a few case reports published in the literature. Chylothorax associated with mediastinal lymphoma was diagnosed in a captive 7-yr-old male striped skunk ( Mephitis mephitis). The animal presented with anorexia and apathy. Supportive care and prednisolone improved the animal's clinical status for 2 wk preceding its death. Histopathology supported the clinical findings, and the tumor was classified as a mediastinal non-Hodgkin lymphoma, stage 2b, which has not been documented in the literature. [ABSTRACT FROM AUTHOR]

ABSTRACT We tested whether striped skunks ( Mephitis mephitis) in Flagstaff, Arizona, USA, could be recognized based on variation in pelage patterns and whether camera position influenced that outcome. We presented 11 volunteers with 2 sets of 24 photographs taken between 1 January and 15 February 2015, one with animals photographed from the side, the other from above. Each set of 24 photographs included 9 pairs, with each pair representing 2 different images of the same animal. Volunteers scored twice as many correct matches and 4-fold fewer false matches when photographs were taken from above. Regardless of camera position, the total number of unique skunks in each set was underestimated (83% of total from above, 75% from side), likely because some skunks had very similar pelage patterns. Our results indicate that variation in nose stripe, back stripe, dorsal and ventral tail pattern, and shape of tail can be used to recognize individual striped skunks but similarity in those characteristics among some individuals may cause total number of unique individuals to be underestimated regardless of camera orientation. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Aleutian disease virus (ADV, Amdovirus, Parvoviridae) primarily infects farmed mustelids (mink and ferrets) but also other fur-bearing animals and humans. Three Aleutian disease (AD) cases have been described in captive striped skunks; however, little is known about the relevance of AD in free-ranging carnivores. This work describes the pathological findings and temporospatial distribution in 7 cases of AD in free-ranging striped skunks. All cases showed neurologic disease and were found in a 46-month period (2010–2013) within a localized geographical region in California. Lesions included multisystemic plasmacytic and lymphocytic inflammation (ie, interstitial nephritis, myocarditis, hepatitis, meningoencephalitis, pneumonia, and splenitis), glomerulonephritis, arteritis with or without fibrinoid necrosis in several organs (ie, kidney, heart, brain, and spleen), splenomegaly, ascites/hydrothorax, and/or encephalomalacia with cerebral microangiopathy. ADV infection was confirmed in all cases by specific polymerase chain reaction and/or in situ hybridization. The results suggest that AD is an emerging disease in free-ranging striped skunks in California. [ABSTRACT FROM AUTHOR]

Striped skunks (Mephitis mephitis) are being kept more commonly as pets in the UK, and may therefore be presented to veterinary surgeons in small animal practice. Appropriate husbandry should be encouraged, including an adequate omnivorous diet and plenty of environmental enrichment. Hand-tame skunks are generally not difficult to handle, but care is important to avoid distressing the skunk and triggering discharge of the noxioussmelling anal sac contents. Common presenting conditions include obesity, metabolic bone disease and dental disease, which may be associated with incorrect feeding; cardiac disease; and parasitic diseases, including endoparasites, ectoparasites and toxoplasmosis. The possibility of zoonotic Baylisascaris spp. infections in imported skunks must also be considered. [ABSTRACT FROM AUTHOR]

ABSTRACT Carnivore guilds play a vital role in ecological communities by cascading trophic effects, energy and nutrient transfer, and stabilizing or destabilizing food webs. Consequently, the structure of carnivore guilds can be critical to ecosystem patterns. Body size is a crucial influence on intraguild interactions, because it affects access to prey resources, effectiveness in scramble competition, and vulnerability to intraguild predation. Coyotes ( Canis latrans), bobcats ( Lynx rufus), gray foxes ( Urocyon cinereoargenteus), raccoons ( Procyon lotor), red foxes ( Vulpes vulpes), and striped skunks ( Mephitis mephitis) occur sympatrically throughout much of North America and overlap in resource use, indicating potential for interspecific interactions. Although much is known about the autecology of the individual species separately, little is known about factors that facilitate coexistence and how interactions within this guild influence distribution, habitat use, and temporal activity of the smaller carnivores. To assess how habitat autecology and interspecific interactions affect the structure of this widespread carnivore guild, we conducted a large-scale, non-invasive carnivore survey using an occupancy modeling framework. We deployed remote cameras during 3-week surveys to detect carnivores at 1,118 camera locations in 357 2.6-km2 sections (3-4 cameras/section composing a cluster) in the 16 southernmost counties of Illinois (16,058 km2) during January-April, 2008-2010. We characterized microhabitat at each camera location and landscape-level habitat features for each camera cluster. In a multistage approach, we used information-theoretic methods to evaluate competing models for detection, species-specific habitat occupancy, multispecies co-occupancy, and multiseason (colonization and extinction) occupancy dynamics. We developed occupancy models for each species to represent hypothesized effects of anthropogenic features, prey availability, landscape complexity, and vegetative land cover. We quantified temporal activity patterns of each carnivore species based on their frequency of appearance in photographs. Further, we assessed whether smaller carnivores shifted their diel activity patterns in response to the presence of potential competitors. Of the 102,711 photographs of endothermic animals, we recorded photographs of bobcats ( n = 412 photographs), coyotes ( n = 1,397), gray foxes ( n = 546), raccoons ( n = 40,029), red foxes ( n = 149), and striped skunks ( n = 2,467). Bobcats were active primarily during crepuscular periods, and their activity was reduced with precipitation and higher temperatures. The probability of detecting bobcats decreased after a bobcat photograph was recorded, suggesting avoidance of remote cameras after the first encounter. Across southern Illinois, bobcat occupancy at the camera-location and camera-cluster scale ( [ABSTRACT FROM AUTHOR]

We provide information on recent records of the 2 subspecies of striped skunk occurring in the northeastern (Mephitis mephitis estor) and northwestern (M. m. holzneri) region of Baja California, Mexico. Most of the recent records for these subspecies come from valleys and suburban zones. [ABSTRACT FROM AUTHOR]

An important prerequisite for the effective use of stable isotopes in animal ecology is the accurate assessment of isotopic discrimination factors linking animals to their diets for a multitude of tissue types. Surprisingly, these values are poorly known in general and especially for mammalian carnivores and omnivores in particular. Also largely unknown are the factors that influence diet-tissue isotopic discrimination such as nutritional quality and age. We raised adult and juvenile striped skunks (Mephitis mephitis) in captivity on a constant omnivore diet (Mazuri Omnivore A 5635). Adults (n=6) and juveniles (n=3) were kept for 7 months and young (n=7) to the age of 50 days. We then examined individuals for stable carbon (δ13C) and nitrogen (δ15N) isotope values of hair, nails, lipid, liver, muscle, bone collagen and the plasma, and cellular fractions of blood. Discrimination values differed among age groups and were significantly higher for young compared with their mothers, likely due to the effects of weaning. Δ15N isotopic discrimination factors ranged from 3.14 (nails) to 5.6‰ (plasma) in adults and 4.3 (nails) to 5.8‰ (liver) for young. For Δ13C, values ranged from−3.3 (fat) to 3.0‰ (collagen) in adults and from−3.3 (fat) to 2.0‰ (collagen) in young. Our data provide an important tool for predicting diets and source of feeding for medium-sized mammalian omnivorous adults integrated over short (e.g. liver, plasma) through long (e.g. collagen) periods and underline the potential effects of age on isotopic values in omnivore diets. [ABSTRACT FROM AUTHOR]

Predicting the geographic spread of wildlife epidemics requires knowledge about the movement patterns of disease hosts or vectors. The field of landscape genetics provides valuable approaches to study dispersal indirectly, which in turn may be used to understand patterns of disease spread. Here, we applied landscape genetic analyses and spatially explicit models to identify the potential path of raccoon rabies spread in a mesocarnivore community. We used relatedness estimates derived from microsatellite genotypes of raccoons and striped skunks to investigate their dispersal patterns in a heterogeneous landscape composed predominantly of agricultural, forested and residential areas. Samples were collected in an area covering 22 000 km2 in southern Québec, where the raccoon rabies variant ( RRV) was first detected in 2006. Multiple regressions on distance matrices revealed that genetic distance among male raccoons was strictly a function of geographic distance, while dispersal in female raccoons was significantly reduced by the presence of agricultural fields. In skunks, our results suggested that dispersal is increased in edge habitats between fields and forest fragments in both males and females. Resistance modelling allowed us to identify likely dispersal corridors used by these two rabies hosts, which may prove especially helpful for surveillance and control (e.g. oral vaccination) activities. [ABSTRACT FROM AUTHOR]

Highlights: [•] 58% (18/31) of skunks presented ONRAB® baits had detectable rabies antibody by week 7 post-vaccination. [•] 100% (25/25) of skunks administered ONRAB® per os had detectable rabies antibody by week 7 post-vaccination. [•] All 10 control skunks succumbed to experimental rabies virus infection. [•] 81% (25/31) of skunks in the ONRAB® bait group survived rabies challenge. [•] 100% (23/23) of skunks administered ONRAB® per os survived rabies challenge. [ABSTRACT FROM AUTHOR]

The article focuses on a survey conducted for analyzing the prevalence of cardiac disease in skunks and is also focused on analyzing the different types of cardiac diseases present in them. The survey was conducted by medical institutions of various countries including Europe, Canada and the U.S. According to survey, various symptoms of the disease found in skunks includes weakness, lethargy and decreased appetite.