Search

The dynamic environmental conditions in highly seasonal systems likely have a strong influence on how species use the landscape. Animals must balance seasonal and daily changes to landscape risk with the underlying resources provided by that landscape. One way to balance the seasonal and daily changes in the costs and benefits of a landscape is through behaviorally-explicit resource selection and temporal partitioning. Here, we test whether resource selection of coyotes (Canis latrans) in Cape Breton Highlands National Park, Nova Scotia, Canada is behaviorally-explicit and responsive to the daily and seasonal variation to presumed costs and benefits of moving on the landscape. We used GPS data and local convex hulls to estimate space use and Hidden Markov Models to estimate three types of movement behavior: encamped, foraging, and traveling. We then used integrated step-selection analysis to investigate behaviorally explicit resource selection across times of day (diurnal, crepuscular, and nocturnal) and season (snow-free and snow). We found that throughout the day and seasonally coyotes shifted foraging behavior and altered behavior and resource choices to avoid moving across what we could be a challenging landscape. These changes in behavior suggest that coyotes have a complex response to land cover, terrain, and linear corridors that are not only scale dependent but also vary by behavior, diel period, and season. By examining the resource selection across three axes (behavior, time of day, and season), we have a more nuanced understanding of how a predator balances the cost and benefits of a stochastic environment. Electronic supplementary material The online version of this article (10.1007/s00442-020-04754-1) contains supplementary material, which is available to authorized users.

Wildlife can respond to urbanization positively (synanthropic) or negatively (misanthropic), and for some species, this is a nonlinear process, whereby low levels of urbanization elicit a positive response, but this response becomes negative at high levels of urbanization. We applied concepts from foraging theory to predict positive and negative behavioral responses of coyotes (Canis latrans) along an urbanization gradient in the Chicago metropolitan area, USA. We estimated home range size and complexity, and metrics of 3 movement behaviors (encamped, foraging, and traveling) using Hidden Markov movement models. We found coyotes exhibited negative behavioral responses to highly urbanized landscapes: coyotes viewed the landscape as lower quality, riskier, and more fragmented (home range size and complexity, and time spent encamped increased). Conversely, we found evidence of both positive and negative responses to suburban landscapes: coyotes not only viewed the landscape as higher quality than natural fragments and equally risky, but also viewed it as fragmented (home range size decreased, time spent encamped did not change, and home range complexity increased). Although the spatial and behavioral responses of coyotes to urbanization became increasingly negative as urbanization increased, coyotes were still able to occupy highly urbanized landscapes. Our study demonstrates how wildlife behavioral responses can be dependent on the degree of urbanization and represents one of the first descriptions of apex predator space use and movement in a highly urbanized landscape., As urbanization increases globally, wildlife must respond. We applied concepts from foraging behavior to determine how coyote movement behavior varies across a gradient of urbanization. In suburban landscapes, coyotes responded positively by requiring less space to live. In highly urbanized landscapes, coyotes responded negatively by requiring more space and spending more time not moving. Despite these challenges, coyotes can thrive in highly urbanized landscapes, such as downtown Chicago, USA.

Wildlife can be exposed to antimicrobial-resistant bacteria (ARB) via multiple pathways. Spatial overlap with domestic animals is a prominent exposure pathway. However, most studies of wildlife-domestic animal interfaces have focused on livestock and little is known about the wildlife-companion animal interface. Here, we investigated the prevalence and phylogenetic relatedness of extended-spectrum cephalosporin-resistant (ESC-R) Escherichia coli from raccoons (Procyon lotor) and domestic dogs (Canis lupus familiaris) in the metropolitan area of Chicago, IL, USA. To assess the potential importance of spatial overlap with dogs, we explored whether raccoons sampled at public parks (i.e., parks where people and dogs could enter) differed in prevalence and phylogenetic relatedness of ESC-R E. coli to raccoons sampled at private parks (i.e., parks where people and dogs could not enter). Raccoons had a significantly higher prevalence of ESC-R E. coli (56.9%) than dogs (16.5%). However, the richness of ESC-R E. coli did not vary by host species. Further, core single-nucleotide polymorphism (SNP)-based phylogenetic analyses revealed that isolates did not cluster by host species, and in some cases displayed a high degree of similarity (i.e., differed by less than 20 core SNPs). Spatial overlap analyses revealed that ESC-R E. coli were more likely to be isolated from raccoons at public parks than raccoons at private parks, but only for parks located in suburban areas of Chicago, not urban areas. That said, ESC-R E. coli isolated from raccoons did not genetically cluster by park of origin. Our findings suggest that domestic dogs and urban/suburban raccoons can have a diverse range of ARB, some of which display a high degree of genetic relatedness (i.e., differ by less than 20 core SNPs). Given the differences in prevalence, domestic dogs are unlikely to be an important source of exposure for mesocarnivores in urbanized areas. IMPORTANCE Antimicrobial-resistant bacteria (ARB) have been detected in numerous wildlife species across the globe, which may have important implications for human and animal health. Wildlife can be exposed to ARB via numerous pathways, including via spatial overlap with domestic animals. However, the interface with domestic animals has mostly been explored for livestock and little is known about the interface between wild animals and companion animals. Our work suggests that urban and suburban wildlife can have similar ARB to local domestic dogs, but local dogs are unlikely to be a direct source of exposure for urban-adapted wildlife. This finding is important because it underscores the need to incorporate wildlife into antimicrobial resistance surveillance efforts, and to investigate whether certain urban wildlife species could act as additional epidemiological pathways of exposure for companion animals, and indirectly for humans.

Natal dispersal plays an important role in connecting individual animal behavior with ecological processes at all levels of biological organization. As urban environments are rapidly increasing in extent and intensity, understanding how urbanization influences these long distance movements is critical for predicting the persistence of species and communities. There is considerable variation in the movement responses of individuals within a species, some of which is attributed to behavioral plasticity which interacts with experience to produce interindividual differences in behavior. For natal dispersers, much of this experience occurs in the natal home range. Using data collected from VHF collared coyotes (Canis latrans) in the Chicago Metropolitan Area we explored the relationship between early life experience with urbanization and departure, transience, and settlement behavior. Additionally, we looked at how early life experience with urbanization influenced survival to adulthood and the likelihood of experiencing a vehicle related mortality. We found that coyotes with more developed habitat in their natal home range were more likely to disperse and tended to disperse farther than individuals with more natural habitat in their natal home range. Interestingly, our analysis produced mixed results for the relationship between natal habitat and habitat selection during settlement. Finally, we found no evidence that early life experience with urbanization influenced survival to adulthood or the likelihood of experiencing vehicular mortality. Our study provides evidence that early life exposure influences dispersal behavior; however, it remains unclear how these differences ultimately affect fitness.

Urban free-roaming dog populations in the developing world are managed by a patchwork of local veterinary practitioners, government programs, and non-governmental organizations with varied effectiveness. While lethal removal is still commonly practiced, vaccination and fertility control methods are increasingly being adopted. Identifying which method(s) provides the most cost effective management is needed to inform dog population managers who seek to limit conflicts like dog bites, the spread of disease, and predation on wildlife. Here we describe an agent-based model that simulates the population of free-roaming dogs in Jaipur, a northwestern Indian city. We then apply various lethal and fertility control methodologies to identify which most effectively lowered the dog population size. This spatially explicit model includes temporal and demographic details of street dog populations modeled after data from the study city. We tested each pairing of control type (lethal or fertility) with search method (how to target efforts) to see their efficacy at altering the city’s dog population size, age structure, sterilization coverage, as well as the number of dogs handled. Models were run for 15 years to assess the long term effects of intervention. We found that the fertility control method that targets areas of the city with the highest percentage of intact bitches outperforms all other fertility control and lethal removal programs at reducing the population size while sterilizing a significantly higher proportion of the population. All lethal program methods skewed population demographics towards significantly younger dogs, thus likely increasing the frequency of conflict with humans. This work demonstrates the benefits of modeling differing management policies in free-roaming dogs.

Baylisascaris procyonis , the raccoon ( Procyon lotor ) ascarid, is a common roundworm parasite of raccoons that is also a well-recognized zoonotic pathogen, and a cause for conservation concern. The transmission dynamics of B. procyonis differ with host population attributes, season, and landscape. We examined how the parasite's population attributes change with season, parasite population structure, and host demographics. We examined 1,050 raccoon gastrointestinal tracts collected from 1996 to 2012. Of the 1,050 raccoons necropsied, 382 (36%) were infected with at least one B. procyonis (x¯=15.8 [95% confidence interval=13.39-18.26]; median=7; range 1-199 worms/host), and populations were overdispersed. There was a seasonal change in prevalence with a peak in October/November. Worm burdens decreased approximately 28% per month from January to June and increased approximately 31% per month from June to December. The sex structure of B. procyonis populations was female-biased (56% female). Host demographics did not impact parasite population attributes. This study provides evidence that B. procyonis populations exhibit a yearly cycle of loss and recruitment that may impact the transmission dynamics of the parasite.

1. The timing of raccoon rabies outbreaks in the eastern USA is non-random and often exhibits a seasonal peak. While fluctuations in disease transmission can be driven by seasonal changes in animal population dynamics, behaviour and physiology, it is still unclear which causal factors lead to seasonal outbreaks of raccoon rabies. 2. We used dynamic network modelling to test which of three seasonally changing factors are most likely responsible for raccoon rabies outbreaks: (i) birth pulses, (ii) changes in social network structure and (iii) changes in social contact duration. 3. In contrast to previous predictions, we found that a change in social contact duration was the single most important driver of rabies seasonality. More specifically, co-denning for thermoregulation during the winter increases the amount of time individuals spend in close contact, which in turn should lead to peaks in rabies transmission during the winter. 4. Increased time spent in close proximity during cold winter months has implications for seasonal disease patterns in raccoon populations across a latitudinal gradient, as well as potentially being important for pathogens transmitted by close contact in other wildlife hosts. 5. Synthesis and applications. By incorporating detailed empirical data describing variation in raccoon contacts into a network modelling framework, it is possible to determine the likely causal mechanisms driving seasonal disease patterns. This can be crucial information for wildlife and public health officials implementing wildlife disease control programmes.

Little is known about the effects that oak forest regeneration treatments consisting of a combination of shelterwood harvesting and prescribed fire have on bats, despite increasing use of these treatments. We quantified changes in bat activity levels in relation to oak forest regeneration treatments consisting of harvesting at 50% and 70% retention levels and prescribed fire in two upland Appalachian hardwood forests in Ohio. We monitored bat activity immediately post-harvest, three growing seasons post-harvest, and after application of prescribed fire to harvested stands before the fourth growing season. Total bat activity levels were higher in thinned and thinned and burned treatments than in unthinned controls in all years, but did not differ between harvest treatment levels immediately post-harvest, three growing seasons post-harvest, or between harvest treatment levels within years. Total bat activity post-prescribed fire changed only in the 50% retention harvest treatment blocks, wherein activity decreased. Activity levels of big brown (Eptesicus fuscus) bats were greater in harvested treatment blocks than controls in all years. Activity levels of eastern red (Lasiurus borealis), and Myotis spp. and tri-colored (Perimyotis subflavus) collectively did not differ among treatment blocks post-fire, but were greater in harvested treatment blocks than controls three growing seasons post-harvest. Community composition was strongly related to vegetation volume, with eastern red bats and Myotis and tri-colored bats displaying positive relationships with clutter in low height strata, and big brown bats displaying a negative relationship with clutter in all height strata. The positive relationship between eastern red and Myotis and tri-colored bats and clutter in low height strata may explain why activity levels of these species decreased post-prescribed fire. Our study suggests that the harvesting component of oak forest regeneration treatments may benefit bats for several years, and that while bat activity levels may decline post-prescribed fire, overall activity levels are nonetheless greater than in unthinned areas.

The proximity of urban green spaces to anthropogenic food sources can promote high densities of predators that may negatively affect breeding birds. Not only can high numbers of predators depress reproduction and survival, but birds may behaviorally respond by avoiding those patches, thereby diminishing the value of urban habitats. During 2010 and 2011, we examined relationships between avian territory density and activity of nest predators in 36 2-ha plots within six urban grassland and early successional parks (sites) near Chicago, Illinois. At the plot (i.e., local) scale, densities of common yellowthroats (Geothlypis trichas), field sparrows (Spizella pusilla), and savannah sparrows (Passerculus sandwichensis) were more strongly linked to habitat characteristics than predators. Song sparrow (Melospiza melodia) and eastern meadowlark (Sturnella magna) densities were not associated with habitat at the plot scale, but together were negatively related to activity of avian predators. Surprisingly...

Infectious disease transmission often depends on the contact structure of host populations. Although it is often challenging to capture the contact structure in wild animals, new technology has enabled biologists to obtain detailed temporal information on wildlife social contacts. In this study, we investigated the effects of raccoon contact patterns on rabies spread using network modelling. Raccoons (Procyon lotor) play an important role in the maintenance of rabies in the United States. It is crucial to understand how contact patterns influence the spread of rabies in raccoon populations in order to design effective control measures and to prevent transmission to human populations and other animals. We constructed a dynamic system of contact networks based on empirical data from proximity logging collars on a wild suburban raccoon population and then simulated rabies spread across these networks. Our contact networks incorporated the number and duration of raccoon interactions. We included differences in contacts according to sex and season, and both short-term acquaintances and long-term associations. Raccoons may display different behaviours when infectious, including aggression (furious behaviour) and impaired mobility (dumb behaviour); the network model was used to assess the impact of potential behavioural changes in rabid raccoons. We also tested the effectiveness of different vaccination coverage levels. Our results demonstrate that when rabies enters a suburban raccoon population, the likelihood of a disease outbreak affecting the majority of the population is high. Both the magnitude of rabies outbreaks and the speed of rabies spread depend strongly on the time of year that rabies is introduced into the population. When there is a combination of dumb and furious behaviours in the rabid raccoon population, there are similar outbreak sizes and speed of spread to when there are no behavioural changes due to rabies infection. By incorporating detailed data describing the variation in raccoon contact rates into a network modelling approach, we were able to show that suburban raccoon populations are highly susceptible to rabies outbreaks, that the risk of large outbreaks varies seasonally and that current vaccination target levels may be inadequate to prevent the spread of rabies within these populations. Our findings provide new insights into rabies dynamics in raccoon populations and have important implications for disease control.

With increasing urbanization, some animals are adapting to human-dominated systems, offering unique opportunities to study individual adaptation to novel environments. One hypothesis for why some wildlife succeed in urban areas is that they are subsidized with anthropogenic food. Here, we combine individual-level movement patterns with diet composition based on stable isotope analysis to assess the degree to which a rapidly growing population of coyotes (Canis latrans) in Chicago consumes anthropogenic resources. We used telemetry to classify coyotes into three groups based on social class and home range composition: (1) residents with home ranges in urban nature preserves; (2) residents with home ranges that had a high proportion of urban land; and (3) transients that had relatively large home ranges and variable use of urban land. We found that natural and anthropogenic resources in this system can be reliably partitioned with carbon isotopes. Mixing models revealed that resident coyotes associated with most urban nature preserves consumed trace to minimal amounts of anthropogenic resources, while coyotes that live in the urban matrix consume moderate (30–50 %) to high (>50 %) proportions of anthropogenic resources. Lastly, we found evidence of prey switching between natural and anthropogenic resources and a high degree of inter-individual variation in diet among coyotes. In contrast to the expectation that urban adaptation may dampen ecological variation, our results suggest individuality in movement and diet exemplifies the successful establishment of coyotes in urban Chicago. Our study also suggests that direct anthropogenic food subsidization is not a prerequisite for successful adaptation to urban environments.

Understanding population structure can lend insight into the spread of animal-borne disease, and the effects of anthropogenic land use on habitat. Raccoons are highly adaptive to human land development and can persist in a wide range of habitat types, making them ideal subjects for investigating the level of population structure in a highly fragmented area. A total of 323 raccoons were livetrapped from 7 locations encompassing 3 distinct habitat types (agriculture, urban forest preserves, and residential) across the Chicago metropolitan region (maximum distance between 2 sites was 128 km). Genetic analyses of 14 microsatellite loci indicate that although raccoon populations across the region share up to 50% of the allelic diversity, they segregated into at least 2 distinct subpopulations, dividing the Chicago metropolitan region into northern and southern groups with further structure occurring within these larger groups. Incorporating sample sites between the identified north– south groups may provide greater resolution as to where this split occurs. Although there is evidence of population structure between all sample sites, migrant analysis suggests there is enough gene flow to preserve genetic diversity throughout the population.

Mammals often use latrine sites for defecation, yet little is known about patterns of latrine use in many common species such as raccoons (Procyon lotor). Because raccoon latrines are important foci for the transmission of raccoon roundworm (Baylisascaris procyonis), documenting metrics of raccoon latrine use may have public health implications. Although some studies have provided evidence that multiple raccoons visit single latrine sites, exact latrine visitation patterns of raccoons have never been documented. We monitored raccoon latrine usage using proximity- logging collars placed at 15 latrine sites. We found that latrine sites were visited by multiple raccoons (range 1-7), and raccoons visited as many as six latrines during a 2-wk period. No sex differences were found in the number of latrines visited or time spent during visits. We posit that the use of multiple latrine sites by raccoons may lead to the pattern that rates of B. procyonis infection at latrines are greater than infection rates found in individual raccoon fecal samples. This in turn could lead to greater transmission of B. procyonis to paratenic hosts. Our results support the conclusion that raccoon latrines can be major foci for the infection and spread of B. procyonis.

Agricultural intensification has led to widespread declines in wildlife biodiversity across many taxa. North American bats provide valuable services for agriculture yet basic ecological understanding of how bats use habitat in intensely agricultural areas is lacking. We examined the movements and resource selection of the federally endangered Indiana bat (Myotis sodalis) in a highly agricultural landscape in central Ohio, USA. We recorded nocturnal movements of 36 Indiana bats during the summers of 2009 and 2010; mean (±SD) fixed-kernel home range area was 212.0 ± 132.4 ha. We examined second- and third-order habitat selection and found that bats selected all habitat types more strongly than cropland at all analysis scales. Woodland was selected more strongly than any other habitat with the exception of open water. However, although bats heavily used a wooded stream corridor, movement was not restricted by large expanses of cropland and bats traversed open, non-forested areas >1 km across to reach small, isolated, wooded patches. The limits and to what extent Indiana bats can persist using small, isolated habitat patches are unknown, but our data support continued emphasis on conservation of riparian habitats and wooded patches within agricultural landscapes. © 2014 The Wildlife Society, 2014.

American badgers (Taxidea taxus) are a prairie obligate species, but badger resource selection and space use is poorly understood, particularly east of the Mississippi River where anthropogenic land uses have replaced most native prairie. We assessed badger multi-scale resource selection and space use in intensive agricultural areas in Illinois and Ohio. We predicted that badgers would select for pasture and prairie, and higher elevations, and riparian areas because these habitats likely favor burrowing and foraging. Conversely, badgers should avoid cropland, roads, and forest at both spatial scales because these habitats may limit burrowing and foraging and potentially increase mortality risk. We also predicted annual male space use would increase with age and be greater than females because of age-related dominance and polygynous mating. We used radiolocations from 18 (11 females, seven males) and five (two females, three males) badgers in Illinois and Ohio, respectively, to estimate space use ...

Raccoons are generally regarded as solitary, yet several studies have found that raccoons frequently form social affiliations. One benefit to sociality in many mammal species is that relatives and close associates can form coalitions against third parties during agonistic encounters. We tested whether raccoon dominance patterns were influenced by age, sex, genetic relatedness, and association patterns at two anthropogenic feeding stations in an urban forest. We found that genetic relatedness had no significant effect on patterns of agonism at one of the feeding stations. At the second feeding station, raccoons were more likely to act aggressively toward close relatives, which is opposite of the predicted pattern. However, when we controlled for the number of times raccoons arrived at feeding stations in close proximity, the effect of relatedness on dominance patterns was not significant at either feeding station. These results suggest that relatedness plays little or no role in shaping dominance patterns of raccoons. Older raccoons were ranked significantly higher in the dominance hierarchies regardless of sex. This pattern leads us to conclude that age is the primary factor driving the outcome of aggressive interactions in raccoons at our study site. Despite frequent social interactions at the study site, the patterns of raccoon dominance more closely resemble patterns found in solitary animals. To confirm the generality of these results and to better understand the evolution of raccoon social behavior, similar studies need to be undertaken in other raccoon populations.

Coyotes (Canis latrans) occur across North America in many types of ecosystems, including urban areas, yet certain aspects of coyote behavior remain obscure. Previous observational studies have provided evidence that coyotes are socially monogamous; however, the degree to which coyotes exhibit genetic monogamy has not previously been determined. We used radiotelemetry and genetic techniques to determine the mating system of an urban coyote population. We obtained samples from 236 coyotes captured during 2000–2006 in the Greater Chicago Metropolitan Area of Illinois. Individuals were genotyped using 12 polymorphic microsatellite markers. Among 18 litters comprising 96 offspring, we found no evidence of polygamy, and detected a single instance of a double litter (pups from different parents sharing the same den). The 2 mated pairs that contributed to the double litter had not interbred. However, the relatedness values shared between 1 mated pair and the pups that were not their offspring suggested that they were closely related, possibly as cousins or grandparents/ grandoffspring. Across all radiocollared mated pairs, mean home range overlap for the male and female was 80.1% (SD 5 13.4). Among 7 mated pairs, 3 of which were radiotracked over multiple years, there was no evidence of mate abandonment and multiyear monogamy was maintained. Despite the high food resources available and high population density, urban coyotes display no variability in their monogamous mating system.

Raccoons (Procyon lotor) are considered synanthropic, with high densities reported from urban landscapes. However, little information is available on population density and demography within the urban matrix. To better understand how urban land-use patterns influence raccoon density and demographic patterns, we sampled raccoons at multiple, replicated sites across an urban landscape. Density differed by land-use type (F2,17 = 4.66, P = 0.027): urbanized sites, = 4.96 ± 2.64 raccoons/km2, range = 1.25–10.00 raccoons/km2; urban open sites, = 14.84 ± 6.35 raccoons/km2, range = 3.00–29.25 raccoons/km2; rural open sites, = 15.50 ± 4.66 raccoons/km2, range = 13.00–20.25. Although we found no clear patterns in sex ratio, reproductive condition, or body condition, we observed differences in age structure among urban open, rural open, and urbanized sites. The most striking difference was the absence of older animals at urbanized sites and relatively low numbers of young individuals at urban open sites. Raccoons were the dominant mesocarnivore in open fragments, but less so in the urban matrix. Spatial variation in density across urban landscapes is likely influenced by site level differences in abundance of anthropogenic resources and differences in habitat quality. Furthermore, the association between changes in land-use and population age structure may have reflected different mortality sources across the landscape. Our results illustrate that wildlife species considered synanthropic may have complex relationships with urban landscapes. © 2012 The Wildlife Society.

Forest management practices, such as shelterwood harvesting, can greatly impact bat habitat relationships. Such practices can alter the amount of structural volume within a forest, which can influence bat foraging patterns. We determined the effects of shelterwood harvests of different retention levels (50% and 70% of full stocking) on bat activity patterns in oak-hickory forests located in southern Ohio. We used the Anabat system to monitor activity during May–September 2006. Our objectives were to quantify the effects of harvesting on structural volume and use the results to explain variations in bat activity. Because harvesting alters vertical structure as well as the total amount of volume within a forest, we also determined the height within the vertical profile where changes in structural volume begin to influence overall and species-specific activity. Overall bat activity did not differ significantly between shelterwood harvest levels, but was significantly different between harvested and control sites, with more passes detected within the harvested sites. Lasiurus borealis (red bat), Eptesicus fuscus (big brown bat), and Lasionycteris noctivagans (silver-haired bat) activity was significantly greater in harvested versus control sites, but did not differ between shelterwood harvest levels. Myotis spp. (Myotis lucifugus (little brown bat) and Myotis septentrionalis (northern Myotis)) and Perimyotis subflavus (tri-colored bat) activity did not vary between shelterwood harvest levels or between harvested and control sites. The greatest reductions in structural volume occurred in the understory to mid-canopy of the shelterwood harvests. Overall activity was most influenced by the amount of volume within 3–6 m above the forest floor, and declined as volume within that height strata increased. Mean bat passes declined by 50% when volume within 3–6 m exceeded 17 m3/ha. Estimated use by L. borealis decreased by 50% at volumes exceeding 1750 m3/ha in the understory to mid-canopy (0–12 m), while E. fuscus and L. noctivagans estimated use was the highest when volumes within 3–6 m were less than 63 m3/ha. Our results suggest that forest management practices that reduce the amount of structural volume in the understory to mid-canopy provide suitable habitat for foraging bats. Quantifying the amount of structural volume at various heights within the vertical profile of the forest can lend valuable insights into overall and species-specific bat activity patterns.

The response of postparturient females to conspecifics at the natal den can provide insights into intraspecific dynamics, particularly the risk of infanticide. In solitary species, the risk of infanticide may be high and mothers are expected to secure dependent young in dens and tolerate little, if any visitation by males. We monitored 10 male raccoons (Procyon lotor) and 11 females from pregnancy through lactation that were equipped with proximity detecting collars during the neonate rearing period (Apr.–Jul.). Natal den trees were identified and proximity detectors were also attached to these trees to document the mother's movements and visitation by conspecifics. A total of 21 den trees (1–8 dens/mother) were used, yielding 337 den-nights of data. Besides those of the mother, 284 visits (0–2.9 visits/night) were recorded and dens were visited by three to 10 individuals. Time spent away from the den by the mother increased with litter age (F = 45.36, P < 0.001, R2 = 0.19). Females who moved...

In urban environments, woodland areas are typically fragmented and subject to invasive species encroachment, woody overgrowth, and natural succession. In response to negative impacts, conservationists and land managers have implemented restoration strategies to enhance the integrity of woodlands. Because woodland habitat is important for bats (Order Chiroptera), alterations to forest structures may affect how bats utilize forest fragments in urban environments. We evaluated relationships among restoration efforts, microhabitat characteristics and overall bat activity, and interspecific variation among bats in response to woodland characteristics. We monitored bats in nine woodland forest preserves representing various stages of restoration within the Chicago metropolitan area in 2004 and 2005. Overall bat activity was positively related to prescribed burning, invasive species removal, and small tree density (7.7-20 cm dbh) and inversely related to shrub density and clutter at 0-6 m heights. There was interspecific variation in response to alterations in woodland structure, with Lasiurus borealis (L. borealis) positively associated with small and medium (20.1-33 cm) tree densities and inversely related to clutter at 0-9 m; Myotis spp. positively associated with canopy cover, clutter at 6-9 m, and small and medium tree densities; and Lasionycteris noctivagans (L. noctivagans) positively associated with more open forests. Eptesicus fuscus (E. fuscus) activity was not strongly associated with any measured vegetation variable. Our results demonstrate bats positively respond to some forms of woodland restoration in urban landscapes. However, species-specific responses to vegetation differed and should be taken into consideration when developing management plans.

An implicit assumption of the mesopredator release hypothesis (MRH) is that competition is occurring between the larger and smaller predator. When significant competition exists, the MRH predicts that larger species should affect population size, through direct predation or the elicitation of avoidance behavior, of smaller predators. However, there have been few manipulations designed to test these predictions, particularly regarding avoidance. To test whether striped skunks (Mephitis mephitis) avoid coyotes (Canis latrans), we intensively monitored 21 radiocollared skunks in a natural area in northeastern Illinois. We identified 2 spatially distinct groups and recorded 1,943 locations from September to November 2003. For each group, testing periods consisted of 4 weeks (2 weeks pretreatment, 1 week treatment, and 1 week posttreatment). We simulated coyote activity during the treatment week by playing taped recordings of coyote howls at 1-h intervals at 5 locations. Additionally, we liberally applied coyote urine to several areas within 20 randomly selected 100 � 100-m grid cells, and used the grid to classify cells as urine-treated, howling-treated, or control. We determined changes in home-range size and location, and intensity of cell use in response to treatment. We found no differences in home-range size related to treatment (P � 0.248). Although weekly differences in home-range drift approached significance when individuals from both tests were pooled (P ¼ 0.071), drift was highly correlated with mean weekly low temperatures (P ¼ 0.004). Use of howling- and urine-treated cells did not vary among weeks (P � 0.307), nor did proportions of locations within howling circles with assumed effective broadcast radii of 50‐200 m (P � 0.851). Examination of our data did not support the prediction that skunks avoid areas of coyote activity on our study site.

With the continuing spread of urban areas, gaining a greater understanding of the effect of human presence on wildlife species is essential for wildlife managers. We determined the influence of anthropogenic resources on home range size and habitat selection of raccoons (Procyon lotor) during summer (June–August) 1996–2000 for 120 raccoons at three sites exposed to varying levels of urbanization and anthropogenic resources, specifically food. Home range estimates were larger (P < 0.05) at the rural site than the suburban and urban sites for both genders. We used compositional analysis to examine raccoon habitat selection at the second-order home range, second-order core area, and third-order home range scales. Woodland was consistently a highly-selected habitat type for both sexes at every spatial scale. Relative to other habitat types, habitat associated with human-related food (human use areas) was selected most often at the urban site, intermediately at the suburban site, and not selected at the rural site. Spatial scale also affected habitat selection. Human use areas were preferentially selected at the second- and third-order level at the urban site, third-order level only at the suburban site, and at neither level at the rural site. Additionally, intersexual differences in habitat selection were reduced at the urban site, with both sexes preferentially selecting for human use areas as well as woodland habitat. Smaller home ranges in urbanized environments are often attributed to the abundant and concentrated anthropogenic resources associated with human activity, but with little empirical support. Our habitat selection analyses followed our predictions that raccoon foraging is strongly influenced by the artificial distribution and abundance of human-related food. Male and female raccoons in urban areas reduce their foraging patterns and focus their foraging activity on anthropogenic foods.

Coyotes (Canis latrans) are an opportunistic predator that have adapted to many human-modified environments. Conflicts between coyotes and humans are an increasing concern for managers in urban areas. We examined the spatial and temporal utilization and availability of natural and human-associated food for coyotes in the Chicago metropolitan area, Illinois, USA. We collected 1429 coyote scats from May 2000 to December 2002, and conducted prey surveys in 2002, in 4 sites that varied in their degree of urban development. Dominant food items included small rodents, white-tailed deer (Odocoileus virginianus), fruit, eastern cottontail (Sylvilagus floridanus) and birds. Their availability and occurrence in scats varied among sites and seasons. The occurrence of human-associated food items, which was only found in significant amounts in the most developed site, varied seasonally (2–25%). Because coyotes in less-developed areas had lower dietary diversity, these coyotes may have to venture into develope...

Some predator species appear to conform to the mesopredator release hypothesis (MRH), in which larger predators help limit populations of smaller predators. This hypothesis has been used to explain the possible relationship between coyotes, mesopredators, and resultant cascades involving nonpredators. However, relationships between coyotes and noncanid mesopredators are poorly understood, and predictions from the MRH have rarely been rigorously tested. We monitored sympatric raccoon and coyote populations to assess 2 predictions derived from the MRH: coyote predation is an important cause of mortality in raccoon populations or raccoons avoid areas used by coyotes. Between March 2000 and September 2001, we recorded 3553 locations for 27 radio-collared raccoons and 1393 locations for 13 coyotes captured on the Max McGraw Wildlife Foundation in Illinois, USA. No raccoon mortality from coyote predation was observed during the study, and raccoon survival was >0.7 each season. All raccoon 95% home ranges exhibited overlap with 95% coyote home ranges in each season. The mean proportion of raccoon locations within 95% coyote home ranges did not vary by sex but did vary by season. Raccoon overlap of coyote core areas varied considerably among individuals within seasons, ranging from 0% to 83%. However, 45% of raccoons had 50% overlap. Mean overlap with core areas did not vary by season or sex. For those raccoons with home ranges overlapping coyote core areas, mean proportion of observed raccoon locations within coyote core areas was generally greater than the mean proportion of random locations. Scent-station experiments failed to document raccoon avoidance of specific sites that had been marked with coyote urine. We did not find support for a mortality prediction or avoidance prediction to support MRH with regard to raccoons and coyotes. These results suggest that relationships among mammalian predators may not be simply dictated by body size, particularly for species outside the Canidae. Copyright 2007.

Long-term data on wildlife populations are needed to elucidate the relative importance of extrinsic factors on population dynamics; however, such data are rare for most species such as medium-sized mammals. We present long-term population indices for Virginia opossums (Didelphis virginiana) and striped skunks (Mephitis mephitis) in Illinois from 1975 to 1998. Annual road-kill indices (RKI) and spotlight indices were correlated for opossums, but not for skunks. Opossum indices exhibited an overall increase (P < 0.01) during the study, but there was no trend since 1983. Skunk RKI exhibited a negative slope (P < 0.01), but this was influenced by a fluctuation in RKI during the late 1970s and there has been no overall trend since. Mean winter temperatures (t − 1) were positively correlated with opossum RKI, but were not correlated with skunk RKI. Estimated harvest (t = 0) was positively related to skunk RKI, and effective harvest was positively correlated with opossum RKI. Annual rabies cases in skun...

Identifying factors that are limiting to populations is fundamental to understanding population dynamics of wildlife, and such knowledge is important for conservation and management. I compared survival and cause-specific mortality patterns between urban and rural populations of striped skunks (Mephitis mephitis) in northeastern Illinois. Rabies, an important mortality factor for skunks, was absent from the study populations. Body weights of skunks declined during winter in both areas, but there was a slightly greater decline for rural skunks. Estimates of annual survival were similar (P > 0.1) between areas, as were seasonal patterns of survival. Disease or poor physical condition was the greatest cause of mortality at the urban site throughout the year, whereas it was the most common mortality factor at the rural site only during winter and spring; vehicle collision was the most common cause of death at the rural site during summer and autumn. I found little evidence that body weight or condition before winter denning, sex, or age were related to survival during winter; however, relationships between these covariates and survival may have been obfuscated by parasites. Results from this study suggest that the winter season is a critical period for survival for skunks from rural and urban areas at temperate climates, anthropogenic factors associated with urban landscapes have minimal effects on skunk survival distributions, and disease is a major cause of mortality even in the absence of rabies.

Common raccoons (Procyon lotor (L., 1758)), Virginia opossums (Didelphis virginiana Kerr, 1792), and striped skunks (Mephitis mephitis (Schreber, 1776)) are common urban inhabitants, yet their relative demographic response to urbanization is unknown. Urbanization often affects community structure, and understanding these effects is essential in rapidly changing landscapes. We examined mesopredator-community structure in small and large patches of natural habitat surrounded by urban, suburban, or rural matrices. We created generalized logit models using road-survey and livetrapping data to examine effects of surrounding land use on proportions of opossums and skunks relative to raccoons, while accounting for effects of season and year and their interactions. For large sites, the land use × season model was chosen for both data sets, and occurrence of opossums and skunks relative to raccoons was higher at the rural site (P < 0.001 for all tests). For small sites, the land-use model best fit the road-survey data, with a higher occurrence of skunks relative to raccoons at the rural site (χ2 = 21.06, df = 1, P < 0.001). However, the season model best fit the trapping data for small sites. Our data indicated that raccoons exhibited a greater demographic response to urbanization, suggesting that they exploit anthropogenic resources more efficiently. Although numerous reasons exist for disparity in anthropogenic-resource use, differences in intraspecific tolerance and the role of learning in foraging behaviors were best supported by our observations.

Abundance and distribution of food resources can profoundly affect movements and spatial distribution of solitary carnivores. Food availability and distribution are often altered in urbanized systems due to occurrence of abundant and highly concentrated anthropogenic resources. To address effects of these resources on movements and spatial distribution of raccoons (Procyon lotor), we simultaneously studied populations inhabiting urban (Ned Brown Forest Preserve), suburban (Max McGraw Wildlife Foundation), and rural (Glacial Park) open areas in northeastern Illinois. Estimates of sizes of home ranges were smaller for urban (range, 25.2–52.8 ha, n ¼ 29) and suburban (21.4–37.2 ha, n ¼ 34) than rural (71.2–182.4 ha, n ¼ 39) raccoons during all seasons (P , 0.05). Seasonal changes in sizes of home ranges were least pronounced at the suburban site. Seasonal shifts in activity centers also were small for raccoons at the suburban site and for most raccoons at the urban site. Spatial distribution was aggregated during all seasons at the urban site, and during all seasons except summer 1997 at the suburban site. Abundant and relatively stable artificial resources typical of urbanized systems contributed to reduced size and increased stability of home ranges. Further, concentration of these resources into rich and separated patches resulted in an aggregated distribution. Similar responses to abundant and concentrated resources have been documented for solitary carnivores in other, more natural, systems.

Urbanization is currently considered to have a negative effect on biodiversity, including the abundance and diversity of bat (Chiroptera) communities. However, relatively little attention has been devoted to the urban ecology of bats despite their ubiquity and ecological importance. We conducted a study during 1997–1999 to acoustically monitor species-specific distributions and activity patterns for bats in a highly urbanized landscape. Of 11 896 passes recorded during the study that satisfied our criterion for species classification, 8672 (73%) were identified to species. We identified calls from five species (Eptesicus fuscus, Lasionycteris noctivagans, Lasiurus borealis, Lasiurus cinereus, Pipistrellus subflavus) and the Myotis group. Few landscape variables were significantly related to E. fuscus activity; however, L. borealis and L. noctivagans activity had positive relationships with adjacent industrial/commercial land use and an urban index. We determined mean occurrence at monitoring sites for all...

We report on intrasexual spatial patterns and dynamic interactions of northern raccoons in eastern Kansas. In general, extensive spatial overlap occurred among female and male dyads in each season and among age classes. The dynamic interaction test revealed positive interaction among 5 of 9 male dyads, and no evidence of negative interaction. Some male dyads denned and traveled together for intervals of varying lengths (2 to 16 days) in each season of the year. There was no evidence of dynamic interaction among female dyads. We provide additional evidence that social behavior of male raccoons exhibits geographic variation, and some level of sociality might be more common than currently described for this species.

Relatively little attention has been devoted to the urban ecology of bats (Chiroptera) despite their ecological importance. Although previous studies have indicated that urbanization has a negative effect on the abundance of bats and bat activity, this relationship may differ among regions. We monitored bat activity during 1997–1999 in 15–20 natural areas distributed across a 3500- km2 area spanning the Chicago metropolitan area in northeastern Illinois. Our objectives were to elucidate relationships between landscape and microhabitat characteristics and bat activity. Bat activity was correlated with visual estimates of abundance. Among adjacent land-use classes, industrial/commercial use was positively related to bat activity in 1997 and 1999, and the predominant rural land use, agriculture, was negatively associated with bat activity in 1998. Proportion of woodland habitat within study areas was positively related to bat activity in every year. There was a positive relationship between agricultural land use and relative use of water sites in each year. Microhabitat analyses revealed that distance between trees was positively related to bat activity in woodlands, and in open habitats there was a relatively strong, negative relationship between distance from the edge and bat activity. Within open habitats, mowed areas had more bat activity than agricultural areas. Our landscape results suggest that the relationship between urbanization and bats may be related to context. Heterogeneous urban landscapes may represent islands of habitat for some bats within larger landscapes dominated by intensive agriculture, such as much of the Midwest.

Context By the early 1900s, river otters (Lontra canadensis) were extirpated across large parts of their range in North America. Over the last several decades they have made a remarkable recovery through widespread reintroduction programs. River otters were reintroduced in Ohio, USA, between 1988 and 1993, and restricted and limited harvesting of this population began in 2005. While circumstantial evidence points to rapid population growth following the reintroduction, changes in population size over time is unknown. Aims We sought to model river otter population growth following reintroduction, and to assess the impact of harvesting. Methods We used empirical and literature-based data on river otter demographics in Ohio to estimate abundance from 1988–2008 using an age- and sex-specific stochastic Leslie matrix model. Additionally, we used statistical population reconstruction (SPR) methods to estimate population abundance of river otters in Ohio from 2006 to 2008. Results Our Leslie matrix model predicted a population size of 4115 (s.d. = 1169) in 2005, with a population growth rate (λ) of 1.28 in 2005. Using SPR methods we found that both trapper effort and initial population abundance influenced our population estimates from 2006 to 2008. If we assumed that river otter pelt price was an accurate index of trapper effort, and if the initial population was between 2000 and 4000, then we estimated the λ to be 1.27–1.31 in 2008 and the exponential rate to be 0.17–0.21 from 2006 to 2008. Conversely, if the river otter population in 2005 was 1000, then we estimated λ to be 1.20 in 2008 and the exponential rate to be 0.08 from 2006 to 2008. Conclusions The river otter population in Ohio appears to have had the potential to grow rapidly following reintroduction. The ultimate effect of the harvesting regime on population abundance, however, remains clouded by limited data availability and high variability. Implications The considerable uncertainty surrounding population estimates of river otters in Ohio under the harvesting regime was largely driven by lack of additional data. This uncertainty clouds our understanding of the status of river otters in Ohio, but a more robust, long-term monitoring effort would provide the data necessary to more precisely monitor the population.

Social dynamics are an important but poorly understood aspect of bat ecology. Herein we use a combination of graph theoretic and spatial approaches to describe the roost and social network characteristics and foraging associations of an Indiana bat (Myotis sodalis) maternity colony in an agricultural landscape in Ohio, USA. We tracked 46 bats to 50 roosts (423 total relocations) and collected 2,306 foraging locations for 40 bats during the summers of 2009 and 2010. We found the colony roosting network was highly centralized in both years and that roost and social networks differed significantly from random networks. Roost and social network structure also differed substantially between years. Social network structure appeared to be unrelated to segregation of roosts between age classes. For bats whose individual foraging ranges were calculated, many shared foraging space with at least one other bat. Compared across all possible bat dyads, 47% and 43% of the dyads showed more than expected overlap of foraging areas in 2009 and 2010 respectively. Colony roosting area differed between years, but the roosting area centroid shifted only 332 m. In contrast, whole colony foraging area use was similar between years. Random roost removal simulations suggest that Indiana bat colonies may be robust to loss of a limited number of roosts but may respond differently from year to year. Our study emphasizes the utility of graphic theoretic and spatial approaches for examining the sociality and roosting behavior of bats. Detailed knowledge of the relationships between social and spatial aspects of bat ecology could greatly increase conservation effectiveness by allowing more structured approaches to roost and habitat retention for tree-roosting, socially-aggregating bat species. Published version

Species occur in urban landscapes under a wide range of conditions and densities, but knowing only the pattern of occurrence provides limited information about species-specific relationships with urbanization. Identifying the specific ways in which urban and non-urban wildlife populations differ and the underlying reasons for those differences is a challenging and complex task. After all, the response of a species to urbanization may be the consequence of wide variety of factors, including life history, behavioral, and physiological attributes that promote avoidance, tolerance, or preference for urban systems. The literature suggests that species that respond negatively to development tend to be habitat specialists, migratory, and/or sensitive to a wide range of human activities and disturbance, whereas species that respond positively are often generalists, omnivorous, multi-brooded, and behaviorally flexible. In this chapter we examine how urbanization affects population structure and demography of species occupying both urban and non-urban landscapes.

We monitored movements of 30 (11 male, 19 female) adult raccoons ( Procyon lotor ) from February 1990 to July 1992 on the Welder Wildlife Refuge, Texas, to identify differences in seasonal sizes of home range between males and females. Sizes of home range of males varied little ( P > 0.05) among seasons, and males had larger ( P < 0.05) home ranges than females in all seasons. There was considerable variation in size of home range among individual females; however, median sizes of home range for females did not change among seasons. Size of home ranges of males were larger ( P < 0.05) than would be expected based on the relationship between body mass and size of home range in mammals and suggested that movements of males were not dictated solely by energetic requirements. Social behavior appears to play an important role in the size of home range of male raccoons.

During the summer of 1985 I had the opportunity to visit Yosemite National Park. The images of my visit that remain with me are not of El Capitan, waterfalls, or wildlife. The images are of humans, and many of them. I remember the traffic-clogged roads, congested hiking trails, low clouds of smoke hanging over crowded campgrounds, a river full of frolicking human bodies, and of course Mirror Lake. Instead of the placid waters and reflections that inspired the name, Mirror Lake had become a public pool. The lake was filled with people; the rock jutting from the middle of the lake that looked so majestic in photographs was veiled with human bodies. I visited Yosemite as a graduate student; although the population problem was known to me, I did not dwell on it. Ten years later, I have a much greater appreciation of the problem, and those images from Yosemite haunt me. As the years pass and the magnitude of the human population problem increases, I fear that Yosemite might be a microcosm of what Earth could become in the near future. Although human population growth is the ultimate challenge facing all conservationists, frank discussions concerning the problem are rare in the flagship publications of conservation-oriented professional societies. I do not know if Conservation Biology is the appropriate venue for human demographic studies (Meffe et al. 1993; Sieving et al. 1994), but certainly there should be more dialogue on the subject. If discussions of population growth are restricted to other outlets, we may be fostering the notion that the human population problem lies outside the domain of natural resource conservation. In the spirit of Meffe et al. (1993) and the relevance of human overpopulation to biodiversity, I wish to make two points that most discussions of human overpopulation neglect. First, the apathy or ignorance the general populace exhibits toward human overpopulation may

We used observations of resting behavior by 38 radiocollared raccoons ( Procyon lotor ) to document late mating for a free-ranging population in southern Texas during 1990–1992. Male-female consortships ( n = 67) exhibited a bimodal distribution each year. In each instance, a second late estrus ( n = 11) occurred after a female failed to produce a litter, or lost a litter soon after parturition. The mean (± SD ) number of days between first and second estrus was 78.6 ± 17.6. Six litters were born between 30 July and 4 September from second matings. Raccoons born as a result of a second estrus may be relatively common, although survivorship of late-born litters is likely low.

Parasites have the potential to influence the population dynamics of mammalian hosts, either as a single devastating pathogen or as a community effect. Striped skunks (Mephitis mephitis) are typically host to rabies, which often regulates population numbers. We assessed micro- and macroparasite dynamics in striped skunk populations in the absence of rabies, to determine if a single pathogen, or community, was responsible for a majority of skunk deaths. We monitored mortality due to pathogens, and prevalence of pathogens via serology and necropsy, in two populations of striped skunks in northern Illinois during 1998-2004. Transmissible pathogens requiring direct transmission (i.e., canine distemper virus, canine parvovirus) exhibited high annual variability in prevalence. In contrast, those pathogens employing a more indirect, environmental route of transmission (i.e., Leptospira interrogans and Toxoplasma gondii) appeared to exhibit relatively less annual variability in prevalence. Skunks were diagnosed with infections from an average of 4.08 (SD=2.52, n=32) species of endoparasites, with a range of 1-11. Macroparasite prevalence and intensity did not vary among seasons, or sex or age of host. Severe infections occurred with multiple parasite species, and patterns of aggregation suggested some parasite species, or more likely the parasite community, act as a limiting mechanism in skunk populations.

The raccoon (Procyon lotor) is the definitive host of Baylisascaris procyonis, a large intestinal roundworm that is zoonotic and can result in fatal or severe central nervous system disease in young children. Prevalence of infection among raccoon populations often is high, and in the midwestern United States, B. procyonis has been reported in 68-82% of raccoons. Raccoon populations have increased in response to changes in human land use, and often reach higher densities in urban and suburban landscapes than rural landscapes. However, shifts in foraging behavior among urban raccoons could impact the transmission of B. procyonis if small vertebrate intermediate hosts are not a significant part of the raccoon diet. The objective of this study was to compare prevalence of B. procyonis infection between urban and rural raccoon populations on a regional scale. Necropsy was done on 204 raccoons collected from September through February during 2000-2005 from seven states across the Midwest (regional sample). Baylisascaris procyonis was found in 54% of examined raccoons. Prevalence differed between land-use types (chi2=11.56, df=1, P=0.0007), and was higher among animals collected from rural locations (65%) than those collected in urban locations (41%). Intensity of infection also differed (F=5.52, df=1, P=0.02), with rural raccoons having greater worm burdens (x=29.63+/-36.42) than urban raccoons (x=13.85+/-18.47). Despite high densities of raccoons in urban landscapes, fewer urban raccoons were infected with B. procyonis, suggesting decreased dependence on intermediate hosts as a food source. This possible explanation was supported by a similar trend in prevalence among subsamples of raccoons collected from three Chicago-area populations (local samples) with differing levels of urbanization, population densities, and foraging behavior that had been intensively monitored during 1995-2002. Decreased transmission of B. procyonis in urban landscapes may be due to decreased predation of intermediate hosts, and contact of juvenile raccoons with B. procyonis eggs may be an important factor in maintaining infections within such populations.

We monitored 74 (41 male, 33 female) radiocollared raccoons (Procyon lotor) from February 1990 to July 1992 on the Welder Wildlife Refuge, Texas, to relate male and female space use to each other and to the spatial distribution of water, a critical resource for raccoons. Female home ranges were spatially aggregated early in the study, when standing water occurred in only a few, widely separated patches on the study site, but were randomly distributed during seasons when water was more widely distributed. Adult females generally foraged and rested independently of other adults. Most adult males were arranged in spatial groups whose home ranges overlapped little with those of adjacent groups. These groups were usually composed of three to four individuals; Doncaster's (1990, J. theor. Biol., 143, 431-443) test for dynamic interaction and visual observations showed that group members tended to associate positively during resting and foraging activities in all seasons. Among raccoons, as among many other mammals, female spatial patterns are apparently determined primarily by resource distribution, whereas male patterns are influenced by the distribution of females. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

Raccoons are an important vector of rabies and other pathogens. The degree to which these pathogens can spread through a raccoon population should be closely linked to association rates between individual raccoons. Most studies of raccoon sociality have found patterns consistent with low levels of social connectivity within populations, thus the likelihood of direct pathogen transmission between raccoons is theoretically low. We used proximity detecting collars and social network metrics to calculate the degree of social connectivity in an urban raccoon population for purposes of estimating potential pathogen spread. In contrast to previous assumptions, raccoon social association networks were highly connected, and all individuals were connected to one large social network during 15 out of 18 months of study. However, these metrics may overestimate the potential for a pathogen to spread through a population, as many of the social connections were based on relatively short contact periods. To more closely reflect varying probabilities of pathogen spread, we censored the raccoon social networks based on the total amount of time spent in close proximity between two individuals per month. As this time criteria for censoring the social networks increased from one to thirty minutes, corresponding measures of network connectivity declined. These findings demonstrate that raccoon populations are much more tightly connected than would have been predicted based on previous studies, but also point out that additional research is needed to calculate more precise transmission probabilities by infected individuals, and determine how disease infection changes normal social behaviors.

Free-roaming cats are a common element of urban landscapes worldwide, often causing controversy regarding their impacts on ecological systems and public health. We monitored cats within natural habitat fragments in the Chicago metropolitan area to characterize population demographics, disease prevalence, movement patterns and habitat selection, in addition to assessing the possible influence of coyotes on cats. The population was dominated by adults of both sexes, and 24% of adults were in reproductive condition. Annual survival rate was relatively high (S=0.70, SE=0.10), with vehicles and predation the primary causes of death. Size of annual home range varied by sex, but not reproductive status or body weight. We observed partitioning of the landscape by cats and coyotes, with little interspecific overlap between core areas of activity. Coyotes selected for natural habitats whereas cats selected for developed areas such as residences. Free-roaming cats were in better condition than we predicted, but their use of natural habitat fragments, and presumably their ecological impact, appeared to be limited by coyotes through intraguild competition.

We simultaneously studied raccoon (Procyon lotor) populations inhabiting urban, suburban, and rural open areas in northeastern Illinois, USA, to examine the effects of urbanization on raccoon demographics. We predicted that raccoon density was higher in urbanized than rural landscapes because of increased survival and reproduction rates and greater site fidelity in urbanized areas. Density estimates for both the urban and suburban sites were greater (P < 0.001) than for the rural site during all seasons. Density estimates for the urban and suburban sites were similar (0.177 ≤ P< 0.603) during 4 of seasons. Percentages of porous females were similar among sites. However, higher proportions of juveniles to adult females captured at the urbanized sites may indicate larger litter sizes. Adult female survival was highest at the urban site during the first 2 years, but dropped due to an unknown disease during the final year. Urban raccoons experienced the fewest mortality sources, whereas rural raccoons experienced the most. Disease was the greatest mortality factor at the urban site, while vehicle-related mortalities dominated at the suburban and rural sites. The high ratio of marked to unmarked raccoons captured may indicate greater site fidelity at urbanized sites. Our data suggest that multiple factors, including increased survival, higher annual recruitment, and increased site fidelity, are jointly responsible for high-density raccoon populations in urbanized areas. Direct management of raccoon numbers in urbanized areas likely will require continuous control measures, because raccoons are capable of quickly repopulating an area after the resident population has been reduced. The most effective control measure may be the reduction of anthropogenic food sources that support raccoons at high densities.