Phylogeny of the Procyonidae (Mammalia: Carnivora): Molecules, morphology and the Great American Interchange

The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morphological characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. Specifically, the highly arboreal and frugivorous kinkajou (Potos flavus) and olingos (Bassaricyon) define one clade, whereas the more terrestrial and omnivorous coatis (Nasua), raccoons (Procyon), and ringtails (Bassariscus) define another clade, with the similar-sized Nasua and Procyon joined as sister taxa in this latter group. These relationships, however, have not been tested with molecular sequence data. We examined procyonid phylogenetics based on combined data from nine nuclear and two mitochondrial gene segments totaling 6534bp. We were able to fully resolve relationships within the family with strongly supported and congruent results from maximum parsimony, maximum likelihood, minimum evolution, and Bayesian analyses. We identified three distinct lineages within the family: a (Nasua, Bassaricyon) clade, a (Bassariscus, Procyon) clade, and a Potos lineage, the last of which is sister to the other two clades. These findings, which are in strong disagreement with prior fossil and morphology-based assessments of procyonid relationships, reemphasize the morphological and ecological flexibility of these taxa. In particular, morphological similarities between unrelated genera possibly reflect convergence associated with similar lifestyles and diets rather than ancestry. Furthermore, incongruence between the molecular supermatrix and a morphological character matrix comprised mostly of dental characters [Baskin, J.A., 2004. Bassariscus and Probassariscus (Mammalia, Carnivora, Procyonidae) from the early Barstovian (Middle Miocene). J. Vert. Paleo. 24, 709-720] may be due to non-independence among atomized dental characters that does not take into account the high developmental genetic correlation of these characters. Finally, molecular divergence dating analyses using a relaxed molecular clock approach suggest that intergeneric and intrageneric splits in the Procyonidae mostly occurred in the Miocene. The inferred divergence times for intrageneric splits for several genera whose ranges are bisected by the Panamanian Isthmus is significant because they suggest diversification well precedes the Great American Interchange, which has long been considered a primary underlying mechanism for procyonid evolution.

Dispersal, philopatry, and genetic relatedness in a social carnivore: comparing males and females

A balance must be maintained between the proportion of individuals dispersing and the proportion remaining philopatric such that inbreeding and resource competition are minimized. Yet the relative importance of dispersal and philopatric behaviour is uncertain, especially for species with complex social systems. We examine the influence of dispersal on genetic relationships of a white-nosed coati (Nasua narica: Procyonidae) population from Panama. Field studies of the coati indicate a social system in which all females are highly philopatric and live in bands while all adult males become solitary at maturity, but do not disperse from the home range of their natal band. Based on analyses of multilocus DNA fingerprints, we confirm that female philopatry is the rule, long-distance dispersal is rare, and that relatedness between most bands is low. However, some new bands result from fission events and these bands retain relatively high relatedness to one another for several years. Adult males inhabiting the home range of a band are closely related to band members. In contrast, males and band members whose ranges do not overlap are unrelated or only slightly related. Adult males are also more closely related to other males whose home ranges they overlap extensively than to males whose home ranges they overlap only slightly. These results indicate that males initially disperse from their natal bands to reduce resource competition and not to avoid inbreeding. Inbreeding avoidance, if it occurs, results from more extensive range movements by males during the mating season.

Altered parasite assemblages in raccoons in response to manipulated resource availability

The role that host aggregation plays in structuring parasite assemblages was examined by experimentally increasing the contact rates of raccoons, Procyon lotor. Two populations of raccoons in southern New York were monitored for 2 years to determine baseline levels of host interaction and to identify the parasite assemblage. In the third year of the study, one population was provisioned with the addition of clumped food resources, while the other was provisioned with equal quantities of dispersed food resources. Remote photography showed that raccoons aggregated at clumped resources but not at dispersed resources, and therefore contact rates between individuals were higher in the site with clumped resources. There were no differences in parasitism between the sites prior to resource augmentation. Among ectoparasites, there were no significant changes in the prevalence or abundance of any species in response to the perturbation. In contrast, across the endoparasite assemblage within and across hosts, the prevalence of infection increased as a result of increased host contact. Strong increases in the prevalence of a few directly transmitted species and slight increases among most species lead to increased evenness in parasite prevalence, suggesting that parasites in this system are transmission limited. In addition, the number of parasite species per host (the parasite infracommunity) was higher in the clumped-resource population. These endoparasite results suggest that intraspecific variation in the species richness of parasite communities of individual hosts, and the prevalence of parasitic species in host populations as assessed across entire parasitic assemblages, is robustly influenced by intraspecific variation in the degree of host contact. Further, these results suggest that anthropogenic changes which alter resource availability may have important consequences for disease transmission in wildlife.

Seroprevalence of Trypanosoma cruzi among eleven potential reservoir species from six states across the southern United States

Trypanosoma cruzi, the causative agent of Chagas' disease, is a substantial public health concern in Latin America. Although rare in humans and domestic animals in the United States, T. cruzi is commonly detected in some wildlife species, most commonly raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana). To increase our understanding of the reservoir host species range and geographic distribution, 11 species of mammals from six states spanning the known range of T. cruzi (Arizona, California, Florida, Georgia, Missouri, and Virginia) were tested for antibodies to T. cruzi using indirect immunofluorescent antibody testing. In addition, culture isolation attempts were conducted on a limited number of animals from Georgia and Florida. Evidence of T. cruzi was found in every state except California; however, low numbers of known reservoirs were tested in California. In general, the highest seroprevalence rates were found in raccoons (0-68%) and opossums (17-52%), but antibodies to T. cruzi were also detected in small numbers of striped skunks (Mephitis mephitis) from Arizona and Georgia, bobcats (Lynx rufus) from Georgia, two coyotes (Canis latrans) from Georgia and Virginia, and a ringtail (Bassariscus astutus) from Arizona. Culture-based prevalence rates for raccoons were significantly greater than those for opossums; however, seroprevalences of raccoons and opossums from several geographic locations in Georgia and Florida were not different, indicating that exposure rates of these two species are similar within these areas. For both raccoons and opossums, seroprevalence was significantly higher in females than in males. No difference was detected in seroprevalence between adults and juveniles and between animals caught in urban and rural locations. Our results indicate that T. cruzi prevalence varies by host species, host characteristics, and geographic region and provides data to guide future studies on the natural history of T. cruzi in the United States.

Landscape ecology of eastern coyotes based on large-scale estimates of abundance

Since their range expansion into eastern North America in the mid-1900s, coyotes (Canis latrans) have become the region's top predator. Although widespread across the region, coyote adaptation to eastern forests and use of the broader landscape are not well understood. We studied the distribution and abundance of coyotes by collecting coyote feces from 54 sites across a diversity of landscapes in and around the Adirondacks of northern New York. We then genotyped feces with microsatellites and found a close correlation between the number of detected individuals and the total number of scats at a site. We created habitat models predicting coyote abundance using multi-scale vegetation and landscape data and ranked them with an information-theoretic model selection approach. These models allow us to reject the hypothesis that eastern forests are unsuitable habitat for coyotes as their abundance was positively correlated with forest cover and negatively correlated with measures of rural non-forest landscapes. However, measures of vegetation structure turned out to be better predictors of coyote abundance than generalized "forest vs. open" classification. The best supported models included those measures indicative of disturbed forest, especially more open canopies found in logged forests, and included natural edge habitats along water courses. These forest types are more productive than mature forests and presumably host more prey for coyotes. A second model with only variables that could be mapped across the region highlighted the lower density of coyotes in areas with high human settlement, as well as positive relationships with variables such as snowfall and lakes that may relate to increased numbers and vulnerability of deer. The resulting map predicts coyote density to be highest along the southwestern edge of the Adirondack State Park, including Tug Hill, and lowest in the mature forests and more rural areas of the central and eastern Adirondacks. Together, these results support the need for a nuanced view of how eastern coyotes use forested habitats.

Differential Habitat Use or Intraguild Interactions: What Structures a Carnivore Community?

Differential habitat use and intraguild competition are both thought to be important drivers of animal population sizes and distributions. Habitat associations for individual species are well-established, and interactions between particular pairs of species have been highlighted in many focal studies. However, community-wide assessments of the relative strengths of these two factors have not been conducted. We built multi-scale habitat occupancy models for five carnivore taxa of New York's Adirondack landscape and assessed the relative performance of these models against ones in which co-occurrences of potentially competing carnivore species were also incorporated. Distribution models based on habitat performed well for all species. Black bear (Ursus americanus) and fisher (Martes pennanti) distribution was similar in that occupancy of both species was negatively associated with paved roads. However, black bears were also associated with larger forest fragments and fishers with smaller forest fragments. No models with habitat features were more supported than the null habitat model for raccoons (Procyon lotor). Martens (Martes americana) were most associated with increased terrain ruggedness and elevation. Weasel (Mustela spp.) occupancy increased with the cover of deciduous forest. For most species dyads habitat-only models were more supported than those models with potential competitors incorporated. The exception to this finding was for the smallest carnivore taxa (marten and weasel) where habitat plus coyote abundance models typically performed better than habitat-only models. Assessing this carnivore community as whole, we conclude that differential habitat use is more important than species interactions in maintaining the distribution and structure of this carnivore guild.

Assessing demographic and epidemiologic parameters of rural dog populations in India during mass vaccination campaigns

Mass vaccination of dogs is a mainstay for efforts to control rabies and other viral pathogens. The success of such programs is a function of the ability to vaccinate sufficient proportions of animals to develop herd immunity. However, fully assessing success in reaching target vaccination-levels and in understanding the outcome of mass vaccination efforts is hindered if insufficient information is available on the demographics of dog populations and the prevalence of the targeted pathogens. While such information can sometimes be gained from questionnaire surveys, greater precision requires direct assessment of the dog populations. Here we show how such information can be gained from surveys of dogs conducted in association with mass-vaccination programs. We conducted surveys of dogs in six villages in rural Maharashtra, India, between February and July 2011 as part of an effort to reduce the risk of human rabies and virus transmission from dogs to wildlife. Mass vaccination efforts were conducted in each village, and paired with blood sample collection and photographic mark-recapture approaches to gain epidemiologic and demographic data. This data in turn facilitated estimates of dog abundance, population density and structure, vaccination coverage, and seroprevalence of antibodies against canine adenovirus (CAV), canine parvovirus (CPV), and canine distemper virus (CDV). The median dog population size for the six villages was 134 (range 90-188), the median dog population density was 719 dogs per km(2) (range 526-969), and the median human:dog ratio for these six villages was 34 (range 30-47). The median household:dog ratio for the six villages was 6 (range 5-8). Following vaccination efforts, the median vaccination coverage achieved was 34% (range 24-42%). The dog populations consisted mostly of adult dogs (67-86%) and the median sex ratio for the study area was male biased (1.55 males per female; range 0.9-2.5). The seroprevalence of antibodies against CAV, CPV and CDV was 68, 88 and 73%, respectively. Mass vaccination campaigns provide an opportunity to obtain vital epidemiological and demographic data, and develop a clearer understanding of the threats and impacts of diseases and disease control measures.

A SEROLOGIC ASSESSMENT OF EXPOSURE TO VIRAL PATHOGENS AND LEPTOSPIRA IN AN URBAN RACCOON (PROCYON LOTOR) POPULATION INHABITING A LARGE ZOOLOGICAL PARK

In urban environments, raccoons (Procyon lotor) may act as reservoirs for an array of pathogenic organisms, presenting spillover risks for human, domestic animal, and captive (zoo) animal populations. Over 5 yr, 159 raccoons from a high-density raccoon population in St. Louis, Missouri (USA), were surveyed for exposure to canine distemper virus (CDV), canine adenovirus 1 (CAV-1); feline parvovirus (FPV; =feline panleukopenia), and several serovars of Leptospira interrogans. Exposure to each of the viruses and two Leptospira serovars (grippotyphosa and icterohemorrhagiae) was detected (prevalence of CDV = 54.1%; FPV = 49.7%; CAV-1 = 6.9%; L. interrogans icterohemorrhagiae = 8.9%; L. interrogans grippotyphosa = 6.3%). Eighty percent of raccoons showed evidence of exposure to at least one of the five primary pathogens, and 39% were positive for multiple species. Among the viruses, there was a significant co-occurrence of CDV and CAV-1. Longitudinal data on a subset of animals revealed that among individuals who were diagnosed as seropositive on first capture, 33-100% became seronegative for the pathogen of interest when reexamined at a later date. Thus, free-ranging urban raccoons have been exposed to multiple infectious agents, some of which may pose risks to humans and to nonvaccinated domestic and captive animal populations.

Seroprevalence of pathogens in domestic carnivores on the border of Madidi National Park, Bolivia

The importance of diseases of domestic animals in the conservation of wildlife is increasingly being recognised. Wild carnivores are susceptible to many of the pathogens carried by domestic dogs and cats and some of these pathogens have caused disease outbreaks and severe population declines in threatened species. The risk of disease spillover from domestic to wild carnivores in South America has not been extensively investigated. This study examined the disease exposure of domestic carnivores living near a protected area in Bolivia. Forty dogs and 14 cats living in three towns on the eastern border of Madidi National Park were sampled. High levels of exposure to canine distemper virus, canine parvovirus, Sarcoptes scabiei and Toxoplasma gondii were found among domestic dogs, with similarly high levels of exposure to feline parvovirus, feline calicivirus and T. gondii being found among domestic cats. If contact occurs between domestic and wild carnivores, disease spillover may represent an important risk for the persistence of wild carnivores in the region. Additional research is therefore necessary to determine if wild carnivores living in proximity to these domestic carnivore populations are being exposed to these pathogens.

Chronology of Range Expansion of the Coyote,

Coyotes (Canis latrans) were historically restricted to central North America. In less than two centuries, however, Coyotes have colonized most of the continent, including much of northeastern North America. Better understanding causes and proximate mechanisms of this expansion requires a detailed understanding of how Coyotes colonized areas on a fine scale. We examined the establishment of Coyotes in the State of New York by collecting and analyzing reports of their first occurrence throughout the state over the past century, and creating a detailed map of range expansion. Coyotes first entered New York from the north, circled the Adirondack region prior to colonizing it, and then expanded southward and westward at ca. 78-90 km/decade. The revealed pattern lends little support to the hypotheses that the range expansion is attributable to translocations and releases, or that Coyotes were historically present in the region and only recently expanded in numbers. Rather, the data suggest a correlative relationship between anthropogenic land use and Coyote range expansion.

Differential effects of experimental increases in sociality on ectoparasites of free-ranging raccoons

1. Parasite transmission depends on the rate at which hosts come into contact with one another or the infectious stages of parasites. However, host contact rates and their influence on parasite transmission are difficult to quantify in natural settings and can fluctuate with host behaviour and the ecological constraints of parasites. 2. We investigated how experimental increases in rates of contact and social aggregation affected ectoparasite prevalence and intensity of free-ranging raccoons (Procyon lotor). Twelve independent raccoon populations were subjected to differential resource provisions for 2 years: a clumped food distribution to aggregate hosts (n = 5 aggregated populations), a dispersed food distribution to control for the effects of food without aggregating hosts (n = 3) and a no food treatment (n = 4). 3. Remote cameras indicated that aggregation sizes and rates of contact were three to four times greater in aggregated compared with that in non-aggregated populations. The number of ticks (adult Dermacentor variabilis) on raccoons in aggregated populations was 1.5-2.5 times greater from May to July, the primary time of tick seasonal occurrence. Conversely, louse (Trichodectes octomaculatus) populations were c. 40% sparser on male raccoons in aggregated (compared with that in non-aggregated) populations because of greater overdispersion of lice and a larger number of male hosts harbouring fewer parasites. No treatment-related differences were found among fleas (Orchopeas howardi). 4. These results were not consistent with our current understanding of parasite transmission; greater rates of host sociality led to increases in a parasite that does not rely on host contact for transmission (ticks) and declines in a parasite that depends on host contact for transmission (lice). We concluded that D. variabilis increased in aggregated sites because they can detect and seek out hosts and were more likely to drop off after obtaining a blood meal and re-attach to raccoons in these locations. Several factors may have contributed to sparser louse populations on male hosts, including a dilution effect that lowered per capita infestation levels. 5. These results indicate that ectoparasites can interact in unique ways with their hosts that are not consistent with other types of parasite species or models of their transmission.