Den Use Research Articles

Den use and heterothermy during winter in free-living, suburban striped skunks

Den use and heterothermy during winter in free-living, suburban striped skunks

Assessing den selection and den characteristics of grizzly bears

Hibernation has evolved as an adaptive strategy to avoid harsh environmental conditions associated with a lack of resources, and the choice of hibernacula can affect the fitness of individuals. Most habitat selection studies, including investigations of overwintering sites, are based on data collected from land inventories or remote sensing databases used in a geographic information system (GIS). Although rarely used, forest stand ecological data gathered at fine spatial scales may enhance our understanding of selection processes. Our objectives were to enhance previous GIS-based investigations of den use by grizzly bears (Ursus arctos) with field-based investigations and determine whether males and females selected dens in response to food availability, within-stand characteristics related to concealment cover, or factors affecting the structural stability of dens. We studied den selection for 10 male and 21 female grizzly bears at the home-range scale and within the den vicinity using data collected at 42 den sites, 168 adjacent sites, and 345 random locations within the Rocky Mountains and boreal forest of Alberta, Canada between 2001 and 2012. Within their autumn home range, male and female grizzly bears selected sites with greater concealment cover, greater canopy cover, and more abundant sweet-vetch (Hedysarum spp.) compared to availability. Poor model performance when comparing den sites to adjacent sites within the den vicinity suggests that male and female grizzly bears select sites at scales larger than 0.1 km. We found no difference in the dimensions and characteristics of dens excavated by males and females, nor in the structural stability of dens dug under a mature tree or in open areas, and no selection for a specific type of mineral soil or percentage of boulders and cobbles. Our results corroborate previous resource selection functions using remote sensing and land inventory data but show that home-range scale analyses can fail to assess selection of potentially influential, ecologically important within-stand characteristics such as food abundance and lateral cover. Within-stand data are typically unavailable through current habitat maps and field data can enhance our understanding of fine-scale selection. To minimize human-bear interactions and disturbances at dens, we recommend integrating field-based investigations to high-priority denning areas identified from resource selection functions, and to further improve conservation efforts, we recommend taking into account within-stand data to describe behaviors occurring during the active and inactive periods. © 2016 The Wildlife Society.

Evolution and function of fossoriality in the Carnivora: implications for group-living

The societies of group-living carnivores that neither hunt nor interact cooperatively may arise due to ecological drivers and/or constraints. In this study we evaluate whether group-living may be intrinsically associated with fossoriality; a link that is well supported in other taxa, but hitherto under-evaluated in the Carnivora. We make two over-arching predictions: i) that fossoriality will be associated with carnivoran sociality; and ii) that this association will be most evident in those species making extended use of subterranean dens. From a meta-analysis of key behavioural, ecological, ontological, and trophic traits, we demonstrate that three quarters of carnivore species exhibit some reliance on underground dens. Congruence between life-history traits and metrics of fossoriality evidenced that: 1) there are phylogenetic, and morphological constraints on wholly fossorial life-histories; 2) fossoriality correlated positively with the extent of offspring altriciality, linked to the use of natal dens; 3) burrow use increased with latitude; and 4) insectivorous carnivores were more fossorial than predatory carnivores. Corroborating work in the Rodentia, fossorial traits associated strongly with carnivoran group-living tendencies, where species utilising subterranean natal dens are 2.5 times more likely to form groups than those that do not. Furthermore, using comparative analyses, we evidence support for an evolutionary relationship between diet, fossoriality and sociality. We propose that fossorial dens act as a safe haven, promoting fitness benefits, territorial inheritance and cooperative breeding. We conclude that, among smaller (<15kg) den-using carnivores, and especially for omnivorous/ insectivorous species for which food resource dispersion is favorable, continued cohabitation at natal dens can promote cohabitation among adults; that is, philopatric benefits leading to (not necessarily cooperative) spatial groups.

Raccoon (Procyon lotor) Diurnal Den use within an Intensively Managed Forest in Central West Virginia

Abstract Intensive forest management may influence the availability of suitable den sites for large den-seeking species, such as Procyon lotor (Raccoon). As part of a Raccoon ecology study on an industrial forest in the Allegheny Mountains of central West Virginia, we radio-tracked 32 Raccoons to 175 diurnal den sites to determine relative use of dens that included cavity trees, rock dens, log piles, slash piles, and exposed limbs. Patterns of den use significantly differed between sexes and among seasons. Overall, we recorded 58 cavity dens in 12 tree species with 7 maternal dens found in 5 tree species. Raccoons selected larger-diameter den trees than available cavity trees and non-cavity trees. Because the abundance of suitable tree cavities is known to influence Raccoon densities and recruitment at fine spatial scales and female Raccoons in this study used tree cavities as maternal den sites, the continued harvest of large-diameter trees (i.e., those capable of developing den cavities) without replace...

Behavioral response to habitat loss in juvenile spiny lobsters

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 521:117-128 (2015) - DOI: https://doi.org/10.3354/meps11125 Behavioral response to habitat loss in juvenile spiny lobsters Katherine A. Heldt1,3,*, William C. Bridges Jr.2, Michael J. Childress1 1Department of Biological Sciences, Clemson University, Clemson, South Carolina 29634, USA 2Department of Mathematical Sciences, Clemson University, Clemson, South Carolina 29634, USA 3Southern Seas Ecology Laboratories, School of Earth, Environmental, and Landscape Sciences, The University of Adelaide, Adelaide 5006 SA, Australia *Corresponding author: katherine.heldt@adelaide.edu.au ABSTRACT: Understanding behavioral changes is important when examining the impacts of rapid environmental change, particularly when critical resources such as protective shelters become locally limited during habitat loss events. In portions of Florida Bay (Florida, USA), cyanobacterial blooms have reduced the availability of large sponges, an important shelter for juvenile Caribbean spiny lobster Panulirus argus. We examined whether juvenile lobsters from regions with and without sponge shelters differed in: (1) aggressive and gregarious behaviors; (2) den use, den sharing, and den fidelity before and after shelter loss; and (3) dispersal from sites with and without artificial shelters. In laboratory experiments where individuals were paired with similar-size conspecifics, habitat type had no influence on aggression and gregariousness, but larger lobsters were more aggressive and shared dens less frequently than smaller lobsters. When these same individuals were placed into groups of 20 in a mesocosm and exposed to shelter loss, individuals from habitats with sponges showed a greater decrease in den use and den sharing than individuals from habitats without sponges. After shelter loss, large lobsters decreased their den use, den sharing, and den fidelity more than small lobsters. When individuals were released at their point of capture in Florida Bay, large individuals were resighted less often than small individuals. This study suggests that lobsters from habitats without sponges may respond differently to future shelter loss and that size plays an important role in determining whether juvenile spiny lobsters share shelters or disperse. KEY WORDS: Caribbean spiny lobster · Social behavior · Panulirus argus · Aggression · Gregariousness · Sponge mortality Full text in pdf format PreviousNextCite this article as: Heldt KA, Bridges WC jr, Childress MJ (2015) Behavioral response to habitat loss in juvenile spiny lobsters. Mar Ecol Prog Ser 521:117-128. https://doi.org/10.3354/meps11125 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 521. Online publication date: February 17, 2015 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2015 Inter-Research.

Hide or die: use of cover decreases predation risk in juvenile North Axmerican porcupines

Abstract In many mammals, juveniles are vulnerable to predators because of their low mobility and small body size. Cover hides juveniles from predators and has been assumed to lower predation risk. However, among mammal species, studies relating use of cover to fitness remain infrequent and have been predominantly performed on ungulates. We measured habitat selection and survival of juvenile North American porcupines (Erethizon dorsatum). We tested whether juveniles selected for cover, use of cover depended on meteorological conditions (there could be a trade-off between predation risk and radiative heat gain during sunny days), and use of cover influenced survival. We also examined how sex, body mass, mobility of the juvenile, and distance to the mother affected survival. We found that juvenile porcupines (14 individuals observed on 299 occasions) selected high protective cover (microhabitat scale) within areas with low herb cover (local scale). Use of cover partly depended on weather, with use of dens d...

Straddling the divide: den use by brushtail possums (Trichosurus vulpecula) in urban parklands

In Australia, brushtail possums (Trichosurus vulpecula) are declining in natural habitats but have adapted to urban environments so readily that some human residents consider them to be a nuisance. Although this situation represents a conundrum for management, the use of urban habitats by the species remains poorly studied. We conducted our study in six urban parklands, a setting that represents an intermediary between a fully-urban and fully-natural environment. To determine factors that influence the presence of hollows in trees and their use by brushtail possums, physical characteristics of 240 mature trees in six parks in the Adelaide Parklands, South Australia were assessed. To investigate hollow use more comprehensively, 18 possums were radio-tracked. Presence of hollows in trees was a function of tree species and tree size, with hollows formed in both exotic and native species. Tree form and number of hollows were significant predictors of the use of hollow-bearing trees by possums. Use of exotic trees was high, with only 34 % of recorded den trees being native (non-indigenous) species. Radio-tracked individuals were relatively sedentary, with an average daytime denning area of 0.08 ha. While the majority of animals used multiple den sites, all individuals favoured a single den. Use of a variety of anthropogenic structures was high, even when trees were available. On average, sites supported ~1.5 brushtail possums per hollow-bearing tree. A correlation between number of hollows per hectare and possum density (r =0.892, P =0.017) suggests that altering a given area’s density of hollows or anthropogenic structures could influence the density of possums within it.

Eurasian badger (meles meles) habitat and sett site selection in the northern Apennines

The principal aim of this research was to study coarsescale habitat selection and distribution of main setts of the Eurasian badger (&lt;em&gt;Meles&lt;/em&gt; &lt;em&gt;meles&lt;/em&gt; L., 1758). The study area extends for 161 Km2 in the hilly territory of southern Lombardy (Italy). The positions of 23 main setts (SP) and 28 random points (RP) were mapped into a GIS. For each point, several environmental characteristics were measured in the field or taken from thematic digital maps. A statistical comparison of the distribution of these characteristics in a circular area (radius 300 m) around each point was carried out. Eurasian badger setts were primarily dug in sheltered places, with high tree cover. The Manly selection index pointed to a strong selection for deciduous woods. Southern slope orientation and the presence of chestnut trees, a potentially important resource for badgers in this area, were also preferred. Similar to other studies, geological and lithological characters and the distance from water did not appear to influence den use. However, the substratum of the study area was mainly formed with sedimentary rocks, loam rocks and sandstones, with also easy-to-dig alluvial soils. Water is a resource easily available over the whole territory, with a well-branched network of rivers and streams. The road network and the presence of urban or industrial infrastructures seem to be a real factor of danger and disturbance, as one of the leading causes of mortality for badgers are road casualties. Our results suggest that badgers of this region are more selective for the sett site than for food resources.

Should I Stay or Should I go? The Influence of Handling by Researchers on Den use in an Arboreal Nocturnal Rodent

AbstractUnderstanding how animals respond to disturbance by investigators is essential for a fair assessment of the presence of bias in routinely used research protocols. It is also an essential prerequisite for anyone interested in animal welfare and ethically sound research. Here, we utilize an automatic logging system to monitor nest box use by PIT‐tagged edible dormice, Glis glis, after standard handling procedures applied during a regular nest‐box monitoring programme. The edible dormouse is an arboreal nocturnal rodent that relies on tree hollows as daytime den sites. We assessed the effect of disturbance on dormice in two ways: whether it affected the decision of an individual to stay in the same den site for a subsequent day and whether it affected the timing of the individual's nocturnal emergence from the den site. We found handling had a strong negative effect on short‐term den use. In addition, females and sexually active individuals were more likely to spend the following day in the nest box. Individuals that had left the den site after our handling returned to them after an average of 4 d. Handling did not have a significant effect on the period of absence, but reproductively active animals returned on average after 3 d, while reproductively quiescent animals returned after more than 5 d. Manipulation did not have a significant effect on the initiation of nocturnal activity. Our study suggests that disturbance by investigators may modify certain aspects of animal behaviour, but this effect is likely to be short term and does not appear to impair the efficacy of routinely practiced capture‐mark‐recapture field protocols.

Response of eastern pygmy possums, Cercartetus nanus, to selective logging in New South Wales: home range, habitat selection and den use

Context Selective logging of native forests creates a mosaic of disturbance histories; however, little is known about how different taxa respond to such a mosaic. Aims We followed adaptive-management principles to test logging and burning impacts on eastern pygmy possums, Cercartetus nanus (Geoffroy and Desmarest, 1817), by undertaking a large-scale field experiment that coincided with harvesting. We predicted that home range would increase after logging because of a reduction in resources (food and/or dens) and because hollows suitable for denning would decrease, resulting in greater use of unlogged patches and alternate dens. Methods We radio-tracked C. nanus in a before-and-after logging experiment to investigate home range, habitat selection and den use. We tracked 50 possums, some individuals for a maximum of 8 months, within control, recently logged and regrowth (5 years since logging) sites. Key results Home ranges were variable (0.04–19.5 ha), with males having significantly larger home ranges. We were unable to detect a difference in home-range size between controls and the first year after logging and burning, or regrowth 5 years after logging. Home ranges comprised a mosaic of disturbed and undisturbed areas, and possums did not avoid logged habitat in their home ranges, indicating that logging did not significantly influence habitat selection. We suggest that possums were not sensitive to selective logging and burning because nectar-producing plants are adapted to fire disturbance and because a variety of den sites were used, most commonly in tree hollows and fallen logs, which were commonly left as logging residue. Indeed, possums frequently denned in logged patches, both recently after logging (63% of dens) and in regrowth 5 years after logging (76% of dens). Counts of fallen hollow logs at each site indicated that their density was not reduced by logging, with regrowth sites having the greatest abundance of logs (260 ha–1). Conclusions The mosaic of disturbance created by selective logging operations did not negatively affect home range or den selection of C. nanus. Implications Ecologically sustainable logging practices that include a range of mitigation measures to protect biodiversity can be compatible with the management of threatened species. Assessment of the effectiveness of these methods often will rely on scientific research.

Denning behaviour of the European badger (Meles meles) correlates with bovine tuberculosis infection status.

Heterogeneities in behaviours of individuals may underpin important processes in evolutionary biology and ecology, including the spread of disease. Modelling approaches can sometimes fail to predict disease spread, which may partly be due to the number of unknown sources of variation in host behaviour. The European badger is a wildlife reservoir for bovine tuberculosis (bTB) in Britain and Ireland, and individual behaviour has been demonstrated to be an important factor in the spread of bTB among badgers and to cattle. Radio-telemetry devices were deployed on 40 badgers from eight groups to investigate patterns of den (sett) use in a high-density population, where each group had one or two main and three to eight outlier setts in their territory. Badgers were located at their setts for 28 days per season for 1 year to investigate how patterns differed between individuals. Denning behaviour may have a strong influence on contact patterns and the transmission of disease. We found significant heterogeneity, influenced by season, sex and age. Also, when controlling for these, bTB infection status interacting with season was highly correlated with sett use. Test-positive badgers spent more time away from their main sett than those that tested negative. We speculate that wider-ranging behaviour of test-positive animals may result in them contacting sources of infection more frequently and/or that their behaviour may be influenced by their disease status. Measures to control infectious diseases might be improved by targeting functional groups, specific areas or times of year that may contribute disproportionately to disease spread.Electronic supplementary materialThe online version of this article (doi:10.1007/s00265-012-1467-4) contains supplementary material, which is available to authorized users.

Temporal patterns of den use suggest polygamous mating patterns in an obligate monogamous mammal

An NRF focal area grant (EZC), NRF incentive funds (CWWP, FD), an NRF SARCHi chair in mammal behavioural ecology and physiology (NCB) and a research fellowship from University of Pretoria (FD).

Denning chronology and den characteristics of American black bears in Mississippi

Winter denning is a critical component of American black bear (Ursus americanus) ecology. Mississippi has a small recolonizing population (about 50 individuals), including the federally-threatened Louisiana black bear (U. a. luteolus), and knowledge of den use is needed to effectively conserve the species. We quantified black bear denning chronology (n = 15) and den use (n = 18) in Mississippi during 2005–2011. Denning was highly variable and females entered dens earlier than males and emerged later; multiple den use by both sexes in a single winter was common. We recorded equal numbers of tree and ground dens, with ground dens at higher elevations surrounded by dense vegetation. With the exception of all bears denning each winter, black bears in Mississippi exhibited denning chronology and characteristics similar to other black bear populations in the southeastern United States.

Changes in Possum Den-Site Use Following Density Reduction: Implications for Conservation and Bovine Tuberculosis Control

The Australian brushtail possum is a pest in New Zealand, as it has caused the decline of a number of native bird species and has become the greatest barrier to the eradication of bovine tuberculosis (bTB) from livestock. As such, possum populations are reduced (i.e., controlled) at a cost of millions of dollars every year. Yet, control is still timely, costly, and not always 100% effective. Behavioral changes in possums have the potential to substantially affect the ability to control possum populations. For example, it is currently unknown whether possums change their behavior, such as den-site use, following control. How possums use dens is an important consideration in controlling bTB, as dens are a potential infection reservoir for both possums and livestock. Knowledge of any changes in den-site use may allow the design of more targeted and efficient control operations that identify potential increases in transmission risk. To investigate changes in den use due to control, possums were fitted with VHF devices, and were tracked to their den sites before and after a control operation that killed approximately 54% of the adult population. The total number of dens they used and the number of times they changed dens were recorded. Density reduction resulted in an increase in the number of times possums changed dens. However, den use was more strongly influenced by the sex of an individual, with males changing their dens more often than females. Density reduction did not appear to result in a change in the number of dens used. Instead, this behaviour was also largely driven by the sex of an individual, with males using more dens than females. This potential increase in transmission risk does not mean that control strategies should not be undertaken, but that managers should keep in mind the likely responses of possums to control and adapt their strategies accordingly. For example, control measures may need to be targeted towards those individuals that use more dens, such as males. This research also further highlights the need for efficient control that reduces populations to very low densities, to negate this potential increase in transmission risk.

Den use, home range and territoriality of the koomal (Trichosurus vulpecula hypoleucus) with implications for current forest management strategies

The koomal (Trichosurus vulpecula hypoleucus) is a declining subspecies (‘near-threatened’), residing largely within the Western Australian jarrah forest, a forest managed for both conservation and for forestry (roughly half is available for logging). Information on the spatial dynamics of koomal is essential to evaluating whether logging prescriptions provide adequate protection for this threatened species. Here we describe the home range and territoriality of koomal, as well as the characteristics and use of their den trees, at multiple sites within the jarrah forest. We also compare the characteristics of den trees used by koomal against logging prescriptions and previous models that estimate availability of den trees. Results suggested that koomal home ranges varied between sites and sexes, with males having the larger home ranges. Koomal also maintained exclusive core territories, probably to protect their den trees from same-sex individuals. Den trees used by koomal had similar characteristics to those outlined in logging prescriptions, but also included two additional characteristics that may improve the retention of trees suitable for koomal: den trees were preferentially of marri (Corymbia calophylla) and wandoo (Eucalyptus wandoo) species, and had some level of canopy connectivity. Overall, findings from this study should help future evaluations of the effectiveness of logging prescriptions in providing adequate den availability for koomal.

Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?

We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the landscape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover types differed from that expected based on the total area of each across the island and varied across all seasons for all habitat types except Cedar Wood. Preference varied among age and sex groups and across seasons with some groups showing opposite selection for the same cover type in different seasons. Species and diameter-class distributions of selected den trees differed from a random sample of trees across the landscape. Species composition of trees with cavities also differed from the species composition across the study area. American beech (Fagus grandifolia—relative abundance 8.7%) was over-represented in the sample of trees with cavities (29.4%) and trees selected as dens (65%); diameter at breast height (dbh) of beech den trees averaged 80.0 cm, whereas all beech trees averaged 71.2 cm. For all species combined, mean dbh of den trees was 78.4 cm as compared to trees with cavities (67.6 cm), or all trees (50.4 cm). The relative availability of large, cavity-prone tree species was related to previous logging practices.

Behavioural responses of wintering porcupines to their heterogeneous thermal environment

Many species use behavioural thermoregulation to cope with changes in their thermal environment. Most studies to date, however, have focused either on ectotherms or on endotherms living in warm environments. Here we used heated taxidermic mounts to characterize microclimates available to North American porcupines during the cold Canadian winter. We then examined activity patterns and microhabitat use of wild individuals to test whether porcupines responded behaviourally to changes in thermal conditions. Dens offered good protection against the cold, and porcupines modified their use of dens as thermal conditions became more constraining. They reduced time spent outside of dens, increased the number of activity bouts in a day, and became more diurnal. When outside of dens, they fed more often, but did not change their use of microhabitats as thermal conditions became most constraining. Microhabitats other than dens were less predictable in the protection they offered against cold temperatures. This may be why porcupines based their behavioural thermoregulation strategy on modulating patterns of den use rather than on selecting warmer microclimates when outside of the den. We hypothesize that selection of microhabitats outside of the den was driven by food acquisition or predation risk.

Den use and Activity Patterns in Female Canada Lynx (Lynx canadensis) in the Northern Rocky Mountains

Knowledge of female behavior while rearing young can have important implications for species conservation. We located dens and analyzed activity (defined as movement between consecutive GPS locations) for nine female lynx with kittens in the northcentral Rocky Mountains in 2005 and 2007. We used GPS tracking collars to quantify the percentage of time a female spent active and her daily distance traveled for each of three reproductive stages, classified as predenning, denning, and postdenning. We also described the use and placement of maternal dens for these females. Female lynx in our study used one to six dens per breeding season, and increased both frequency of den relocation and distance between dens as kittens matured. Females typically left the den twice a day, and were gone for an average of five hours at a time. Females were active for 56% of a given 24 hour period during predenning, 48% during denning, and 61% during postdenning. Females traveled greater distances in 24 hours during predenning than denning. We conclude that reproductive female lynx alter the amount of time they spend active and daily distance traveled based on reproductive status.

Restes pléistocènes de panthera leo spelaea (goldfuss 1810) de la grotte de Balve (NO de l’Allemagne) – une grotte à ours des cavernes, une tanière de hyène et un habitat du paléolithique moyen - et révision des sites à lions des grottes du Karst du Sauerland

Pleistocene remains of Panthera leo spelaea (Goldfuss 1810) from Balve Cave (Sauerland Karst, NW-Germany), one of the most famous Middle Palaeolithic Neandertalian cave sites in Europe, and also a hyena and cave bear den, belong to the most important felid sites of the Sauerland Karst. The stratigraphy, macrofaunal assemblages and Palaeolithic stone artefacts range from the final Saalian (late Middle Pleistocene, Acheulean) over the Middle Palaeolithic (Micoquian/Mousterian), and to the final Palaeolithic (Magdalenien) of the Weichselian (Upper Pleistocene). Most lion bones from Balve Cave can be identified as early to middle Upper Pleistocene in age. From this cave, a relatively large amount of hyena remains, and many chewed, and punctured herbivorous and carnivorous bones, especially those of woolly rhinoceros, indicate periodic den use of Crocuta crocuta spelaea. In addition to those of the Balve Cave, nearly all lion remains in the Sauerland Karst caves were found in hyena den bone assemblages, except those described here material from the Keppler Cave cave bear den. Late Pleistocene spotted hyenas imported most probably Panthera leo spelaea body parts, or scavenged on lion carcasses in caves, a suggestion which is supported by comparisons with other cave sites in the Sauerland Karst. The complex taphonomic situation of lion remains in hyena den bone assemblages and cave bear dens seem to have resulted from antagonistic hyena-lion conflicts and cave bear hunting by lions in caves, in which all cases lions may sometimes have been killed and finally consumed by hyenas. The lion remains, and not only in the Balve Cave seem to have been selected, as suggested by cranial and distal limb bone overrepresentations, which consist of 99 % of grown ups and with 58 % remains of dominantly females. Such limbs, and especially the pedal bone dominance, is not a criterion for human hunt and fur import, on the contrary, at hyena dens all prey remains are overrepresented by distal leg remains, a fact also very well known in the case of horse remains. The only articulated lion cub skeleton remain in the Sauerland Karst from the Wilhelms Cave might indicate a hyena kill that seems to be imported into the much frequented cub raising hyena den site.

Resource use overlap between urban carnivores: Implications for endangered San Joaquin kit foxes (Vulpes macrotis mutica)

An urban population of Endangered San Joaquin kit foxes (Vulpes macrotis mutica) has persisted in the city of Bakersfield, (Kern County, California), for several decades. Urban kit foxes may play an important role in future range wide recovery efforts for the species. As such, a comprehensive understanding of the issues that can influence the long-term survival of this population is essential for the development of effective management strategies. Although urban kit foxes have been studied extensively in Bakersfield, interactions between kit foxes and other urban carnivore species are poorly understood. Urban environments can provide a number of opportunities for species to interact in ways not usually observed in natural habitats. Interactions between urban populations of striped skunks (Mephitis mephitis) and kit foxes were investigated at denning locations and cat feeding stations on the California State University-Bakersfield campus, California, USA. A total of 130 individual denning sites were identified, of which 39 (30%) were used by both species. Simultaneous den use by foxes and skunks was recorded on four occasions. Inter and intra-specific aggression was recorded at cat feeding stations on ten separate occasions including three incidences of aggression towards kit foxes by skunks and feral cats (Felis catus). Telemetry data and cat feeding station observations clearly show that interspecific contact does occur in urban environments.