Vulnerable island carnivores: the endangered endemic dwarf procyonids from Cozumel Island

Insular carnivores represent some of the most critically threatened species, but also the least known. To evaluate the conservation status of these species, thorough abundance estimates are urgently required. To better understand the population biology and conservation status of the endemic and threatened pygmy raccoon (Procyon pygmaeus) and dwarf coati (Nasua nelsoni) on Cozumel Island, Mexico, we worked island-wide to identify the presence of these species, and for the pygmy raccoon we studied several populations in depth during 2001–2003. On Cozumel, trapping was conducted for >6,600 trap nights in 19 locations of varying habitat types. A total of 96 pygmy raccoons (47 males and 49 females) and a single adult, male dwarf coati (N. nelsoni) were captured. Estimated total annual pygmy raccoon population size ± SE was 80 ± 26.1, resulting in an average density of 22 ± 5.1 raccoons/km² for the three small sites where the animals persist. Based in part on the findings of this study that indicate these species have a restricted range and small population numbers, the IUCN recently changed the listing of the pygmy raccoon to Critically Endangered from Endangered. In contrast, the status of the dwarf coati (Endangered) has not been changed, although the taxon is in eminent danger of extinction and in need of immediate conservation action.     

Conservation genetics of two critically endangered island dwarf carnivores

Genetic diversity is crucial for conservation biology and for understanding evolutionary processes. Oceanic islands harbor a unique biota and high endemism, with populations frequently facing detrimental genetic processes (e.g. drift, bottlenecks). Human activities like habitat transformation further increase extinction risk of insular biota. Mammals comprise the most endangered group among insular fauna. Our aim was to evaluate the genetic and evolutionary patterns of two critically endangered dwarf carnivores from Cozumel Island, the pygmy raccoon (Procyon pygmaeus) and the dwarf coati (Nasua nelsoni), at both historical and contemporary evolutionary scales. We also reviewed their genetic relationships with their mainland counterparts (P. lotor, N. narica), not intended to describe their phylogeny but to ascertain their endemism. Our mitochondrial results support that both Cozumel carnivores are divergent from continental populations, strengthening their endemic status. Both species showed moderate levels of nuclear genetic diversity that were, as expected for island populations, lower in comparison with their mainland congeneric species; they also exhibited significantly low population sizes. We documented historical and contemporary bottleneck signals for P. pygmaeus, whereas N. nelsoni may be suffering the initial stages of a bottleneck not yet fully manifested. The pygmy raccoon is structured into two isolated genetic clusters likely due to interactions with humans on the north of the island, where most potential for disease transmission and health problems exist. We also add evidence about the introduction of the mainland species into the island, risking genetic introgression and hybridization. We discuss specific conservation measures that should include our genetic information, directed to the long-term viability of these endemic carnivores.

     

Diet of brown-nosed coatis and crab-eating raccoons from a mosaic landscape with exotic plantations in southern Brazil

We described the diets of two procyonids, the brown-nosed coati Nasua nasua and the crab-eating raccoon Procyon cancrivorus, through analysis of stomach contents of road-killed specimens in southern Brazil. We compared them with previously published dietary information for another syntopic mesopredator, the crab-eating fox Cerdocyon thous. The landscape of the study area includes native grasslands, forests, exotic tree plantations, and other crops. Food items were represented by frequency of occurrence (FO) and relative volume (RV). Stomach contents of 23 coatis were analyzed. Animal and plant items were equally frequent, although the volume of plants was greater. Exotic plant species were consumed more than native plants. Among prey items, invertebrates were more important than vertebrates, mainly because of the frequency of coleopterans and annelids and the volume of necrophagous dipteran larvae. Five specimens of raccoons were analyzed, in which animal items had the highest FO and plant items had the highest RV. Both invertebrate and vertebrate prey had the same FO, although vertebrates had a higher RV. Our data suggest that these procyonids are opportunistic hypocarnivores, utilizing anthropic sources, with diet overlap. The coatis also overlapped their diet substantially with the foxes. The stomach-contents analysis revealed the importance of fruit pulp biomass, soft-bodied animals such as larvae, and also soil, which might indicate feeding habits such as scavenging and geophagy.     

New insights on the geographical origins of the Caribbean raccoons

The introduction of species outside their natural range is one of the major threats to biodiversity and has often been identified as a menace to agricultural production and human health. The raccoon is recognized as a globally invasive species. However, several populations in the Caribbean were long considered native and endemic species. Although previous genetic studies have shown that raccoons from the islands of the West Indies belong to the northern raccoon Procyon lotor, the history and origin of these introductions remain poorly known. In this study, we investigated the geographical origin of Caribbean raccoon populations using newly available molecular genetic data. We used haplotype network analyses of two mitochondrial markers, Cytochrome b and Control Region, with new sequences and those from GenBank. We also specifically investigated the origin of the endangered endemic Cozumel raccoon, Procyon pygmaeus, by re-analyzing data. Our results confirmed that all Caribbean raccoon populations belong to the northern raccoon. Bahamian populations originated from two different sources in Florida, and the Lesser Antilles raccoons seem to originate from northern regions of the native range. In addition, our results question the taxonomic status of the Cozumel raccoon, as currently available genetic data support a conspecific status with the northern raccoon. These results have important implications in the context of conservation and ecosystem management. Identifying origins of introduced populations and understanding the history of their introductions will facilitate studies on the impact of the raccoon on insular ecosystems.     

Interspecific association between an ungulate and a carnivore or a primate

In the Brazilian Pantanal, we observed collared peccaries (Pecari tajacu) associating with South American coatis (Nasua nasua) 13 times and three times with black howler monkeys (Alouatta caraya). The scansorial coati drop fruit whilst feeding that both collared peccaries and other coatis consume. Young coatis were also observed chewing on the pulp left over from seeds spat out by collared peccaries who had removed the hard exocarp. Both species react to each other’s alarm calls. Peccaries also benefited from the fruits dropped by black howler monkeys. Ecologically, coatis are omnivores; but taxonomically, they are carnivores. To our knowledge, the collared peccary/coati association is the first report of an interspecific association between an ungulate and a carnivore.     

Intraspecific, interspecific, and seasonal differences in the diet of three mid-sized carnivores in a large neotropical wetland

The diet and partitioning of food resources among mid-sized mammalian carnivores is poorly known, especially in the tropics. We evaluated the resource partitioning between Leopardus pardalis (ocelot), Cerdocyon thous (crab-eating fox), and Nasua nasua (brown-nosed coati) in the Pantanal of Brazil. Between December 2005 and February 2008, we collected data necessary to better understand interspecific, intraspecific, and seasonal variability in diet. Food habits were assessed by analysis of feces (n?=?293) collected from known individuals (n?=?128), and differences in dietary composition were evaluated through nonmetric dimensional scaling using the Jaccard similarity index. The main diet differences were observed between the specialist ocelot and the more generalist crab-eating fox and brown-nosed coati. Crab-eating foxes and brown-nosed coatis preyed on arthropods, fruits, and vertebrates whereas ocelots preyed almost entirely on vertebrates, mainly rodents and snakes. Ocelots’ consumption of snakes was the highest ever recorded, as was the extent of carnivory by brown-nosed coatis. For the crab-eating fox and the brown-nosed coati, there were large differences between the use of fruits and animal foods in the wet and dry season. Yet for both species there were no significant differences in the diets of males and females. Despite the conspicuous sexual dimorphism and spatial segregation that are typical of brown-nosed coatis, the results do not support the hypothesis that size dimorphism is primarily an adaptation to reduce intersexual competition for food. Rather, dimorphisms and patterns of space use may be more related to competition among males for access to females.     

A serological and fecal parasitologic survey of the critically endangered pygmy raccoon (Procyon pygmaeus)

The pygmy raccoon (Procyon pygmaeus) of Cozumel Island, Mexico, is among the most endangered carnivores in the world, and causes of its decline are unclear. During 2002 and 2003, we sampled approximately 10% of the remaining population to survey exposure to viral and parasitic pathogens that may have contributed to population decline. We found evidence of exposure to infectious canine hepatitis, canine distemper, feline panleukopenia virus, and Toxoplasma gondii. The latter is suggestive of spillover from domestic cats, which have only recently been introduced to the island. Additional parasites identified include Eimeria nutalli, Placoconus lotoris, Capillaria procyonis, Physaloptera sp., a mite in the family Listrophoridae, and a trematode in the family Heterophyidae. Several of these are typical of the parasite community of the common raccoon (Procyon lotor).     

Distribution,abundance, and habitat use of introduced <Emphasis Type="Italic">Boa constrictor</Emphasis> threatening the native biota of Cozumel Island,Mexico

Species introductions are among the most pervasive types of disturbance, seriously affecting island biota and ecosystem dynamics. The management of introduced generalist species, which may live in a wide range of environmental conditions, can be particularly difficult and is a major challenge for the conservation of native insular species. Boa constrictor was introduced onto Cozumel Island, Mexico, in 1971. The introduction of this generalist predator has affected negatively the native species (many of them endemic to the island) on which the boa feed. It is important to determine temporal variation in boa abundance, the areas of the island in which boas live, and the vegetation types they use in order to develop management strategies to reduce boa pressure on the native biota. We used nocturnal road transect sampling and occasional boa encounters during field work, to estimate boa distribution, abundance and habitat use, taking into account its spatiotemporal patterns on Cozumel Island. This study confirms that Boa constrictor is well established, widespread, and abundant on the island. Our results show that boas are distributed throughout Cozumel, in all vegetation types and geographical regions. Overall, there were 0.11 ± 0.03 boa/10 km road transect. There were no significant spatiotemporal differences in boa activity (time of day) and abundance (monthly, seasonally, by vegetation types or regions of the island). According to the habitat use analysis, there were, however, fewer boas than expected in the subdeciduous tropical forest we sampled and in the central-northern region of the island, which coincide with areas inhabited by humans. There were more boas in areas uninhabited by humans, and there was a tendency towards a greater proportion of dead boas in inhabited areas and live boas in uninhabited areas. Cozumel boas are habitat generalists, which are affected by human induced mortality in inhabited areas. There is a vast area uninhabited by humans, with natural vegetation, on the island where boas have suitable habitats available for their continuous existence on Cozumel. This situation, and the adaptability of the boa, makes the control or eradication of this introduced species a critical conservation challenge.     

Bovine tuberculosis in free-ranging carnivores from Michigan

During a survey of carnivores and omnivores for bovine tuberculosis conducted in Michigan (USA) since 1996, Mycobacterium bovis was cultured from lymph nodes pooled from six coyotes (Canis latrans) (four adult female, two adult male), two adult male raccoons (Procyon lotor), one adult male red fox (Vulpes vulpes), and one 1.5-yr-old male black bear (Ursus americanus). One adult, male bobcat (Felis rufus) with histologic lesions suggestive of tuberculosis was negative on culture but positive for organisms belonging to the Mycobacterium tuberculosis complex when tested by polymerase chain reaction. All the tuberculous animals were taken from three adjoining counties where M. bovis is known to be endemic in the free-ranging white-tailed deer (Odocoileus virginianus) population. There were two coyotes, one raccoon, one red fox, and one bobcat infected in Alpena county. Montmorency County had two coyotes and one raccoon with M. bovis. Two coyotes and a bear were infected from Alcona County. These free-ranging carnivores/omnivores probably became infected with M. bovis through consumption of tuberculous deer. Other species included in the survey were opossum (Didelphis virginiana), gray fox (Urocyon cinereoargenteus), and badger (Taxidea taxus); these were negative for M. bovis.     

Raccoons in Europe: disease hazards due to the establishment of an invasive species

From the past, species have been transferred among ecosystems trough traveling and global trade. The establishment and spread of such invasive species has caused significant damage to the economy, the environment, and human or native species health. This review compiles information on infections or contact with pathogens reported in raccoons (Procyon lotor). Raccoons are opportunistic carnivores native to North America. However, nowadays they are distributed across mainland Europe as a result of escaped pets and introductions. In their native range, raccoons are known to be host to a number of disease agents that could be transmitted to humans, domestic animals and other wildlife. Hence, the increase of raccoon populations and their geographic spread in Europe may result in new disease hazards. Raccoons have been identified as possible sentinels of diseases such as West Nile virus, and they pose a disease-related conservation risk by maintaining circulation of canine distemper virus. They also have the potential to participate in the maintenance of zoonoses including the raccoon roundworm Baylisascaris procyonis. Due its fast expansion and the large list of diseases, we conclude that the introduction of the raccoon has had adverse effects on health in Europe. This might well be the case of other invasive species, too. Hence, studies on invasive species health aspects are urgently needed to assess the risk of disease spread and eventually establish control measures.     

Raccoons (Procyon lotor) in Germany as potential reservoir species for Lyssaviruses

Raccoons can be found almost everywhere in Germany since their first successful introduction in 1934. Although the animal is a well-known reservoir species for rabies in the USA, during the last European fox rabies epizootic, only a few rabid raccoons were reported from Germany. In recent years, the raccoon population density has increased tremendously, especially in (semi) urban settings. Presently, Germany is free of terrestrial wildlife rabies. To assess the potential risk that the raccoon population in Germany could act as a reservoir species upon reemergence of rabies, the susceptibility of the local raccoon population was investigated. Wild-caught animals were inoculated with the most likely lyssavirus variants to infect the local population. It was shown that the raccoons were fully susceptible for a dog and raccoon rabies virus isolate. Also, five of six raccoons inoculated with a fox rabies virus isolate showed clinical signs. However, none of the raccoons infected with European Bat Lyssavirus type 1 succumbed to rabies; meanwhile, all these raccoons seroconverted. It is concluded that the highest risk for the raccoon population in Germany to become infected with lyssaviruses is through the importation of rabies infected dogs.     

Cone photopigments in nocturnal and diurnal procyonids

Summary Procyonids are small, New World carnivores distributed among some 6 genera. Electroretinogram (ERG) flicker photometry was used to measure the spectra of the cone photopigments for members of two nocturnal species, the raccoon (Procyon lotor) and the kinkajou (Potos flavus), and a diurnal species, the coati (Nasua nasua). Each of the 3 has a class of cone photopigment with maximum sensitivity in the middle to long wavelengths. The spectral positioning of this cone is different for the three. Whereas the raccoon and kinkajou are monochromatic, the diurnal coati is a dichromat having an additional class of cone photopigment with peak sensitivity close to 433 nm.Abbreviations ERG electroretinogram - SWS short wavelength sensitive     

Exposure of Free-Ranging Wild Carnivores and Domestic Dogs to Canine Distemper Virus and Parvovirus in the Cerrado of Central Brazil

Human population growth around protected areas increases the contact between wild and domestic animals, promoting disease transmission between them. This study investigates the exposure of free-ranging wild carnivores and domestic dogs to canine distemper virus (CDV) and parvovirus in Emas National Park (ENP) in the Cerrado savanna of central Brazil. Serum samples were collected from 169 wild carnivores, including the maned wolf (Chrysocyon brachyurus), crab-eating fox (Cerdocyon thous), hoary fox (Pseudalopex vetulus), puma (Puma concolor), ocelot (Leopardus pardalis), pampas cat (Leopardus colocolo), jaguarundi (Herpailurus yagouaroundi), striped hog-nosed skunk (Conepatus semistriatus) and coati (Nasua nasua), and from 35 domestic dogs living on rural properties bordering ENP. Serological tests showed that 10.6% of wild carnivores (maned wolves, crab-eating foxes and ocelots) and 71.4% of domestic dogs were exposed to CDV, and 56.8% of wild carnivores, including all species sampled except coatis, and 57.1% of domestic dogs were exposed to parvovirus. This report is the first to indicate that the free-ranging pampas cat, jaguarundi and striped hog-nosed skunk are exposed to parvovirus. CDV and parvovirus deserve attention in ENP, and it is extremely important to monitor the health of carnivore populations and perform molecular diagnosis of the viruses to determine the possible involvement of the domestic dog in their transmission.     

Determination of semen characteristics and sperm cell ultrastructure of captive coatis (Nasua nasua) collected by electroejaculation

Despite the wide geographical distribution of coati (Nasua nasua) from the south of Canada to the north of Argentina, studies regarding the reproductive characteristics of this species are extremely limited. The objective of this study was to describe the various characteristics of coati semen by morphometric and ultrastructural analysis. Five mature males were anesthetized and electroejaculated for the collection of semen. Semen was immediately evaluated for color, volume, pH, sperm motility, vigor, morphology, acrosomal integrity, percentage of live cells and hypo-osmotic response by light microscopy. Sperm cell morphometry and ultrastructural analyses were also performed. Observations of seminal characteristics determined by electroejaculation in captive coatis represent a valuable baseline dataset for establishing fertility standards and provide background information that may be useful for assisted breeding programmes in members of the Procyonidae family.     

Infestation of arboreal nests of coatis by triatomine species,vectors of Trypanosoma cruzi,in a large Neotropical wetland

The coati (Nasua nasua, Carnivora) is a medium‐sized mammal common in the Pantanal of Brazil. Unlike most mammals, coatis construct arboreal nests used for resting and reproduction. In this region, the coati is an important host of Trypanosoma cruzi, the causative agent of Chagas disease. There are two possible routes through coatis can be infected by T. cruzi: the oral route or the vectorial route. However, the relative importance of each of these routes in the infection of coatis and its role in the sylvatic cycle of the parasite are unknown. Our objectives were to investigate: (i) whether coati nests were infested by triatomine bugs, (ii) what species were frequent in the nests, (iii) whether the triatomines in nests were infected by T. cruzi, and (iv) what were the food resources of these triatomines. Eight of the 24 nests sampled were infested with triatomines, a total of 37 specimens of at least two species (Rhodnius stali and Triatoma sordida). In one nest, R. stali and T. sordida co‐occurred and both fed on multiple resources, including coatis. This is the first report of triatomines occurring in arboreal nests of coatis. The co‐occurrence of two different genera of triatomine vectors and coatis within the limited space of the coati nests provide multiple opportunities for the exchange of the protozoan parasite through both the vectorial and oral transmission routes.     

Genetically different isolates of Trypanosoma cruzi elicit different infection dynamics in raccoons (Procyon lotor) and Virginia opossums (Didelphis virginiana)

Trypanosoma cruzi is a genetically and biologically diverse species. In the current study we determined T. cruzi infection dynamics in two common North American reservoirs, Virginia opossums (Didelphis virginiana) and raccoons (Procyon lotor). Based on previous molecular and culture data from naturally-exposed animals, we hypothesised that raccoons would have a longer patent period than opossums, and raccoons would be competent reservoirs for both genotypes T. cruzi I (TcI) and TcIIa, while opossums would only serve as hosts for TcI. Individuals (n = 2 or 3) of each species were inoculated with 1 × 10⁶ culture-derived T. cruzi trypomastigotes of TcIIa (North American (NA) – raccoon), TcI (NA – opossum), TcIIb (South American – human), or both TcI and TcIIa. Parasitemias in opossums gradually increased and declined rapidly, whereas parasitemias peaked sooner in raccoons and they maintained relatively high parasitemia for 5 weeks. Raccoons became infected with all three T. cruzi strains, while opossums only became infected with TcI and TcIIb. Although opossums were susceptible to TcIIb, infection dynamics were dramatically different compared with TcI. Opossums inoculated with TcIIb seroconverted, but parasitemia duration was short and only detectable by PCR. In addition, raccoons seroconverted sooner (3–7 days post inoculation) than opossums (10 days post inoculation). These data suggest that infection dynamics of various T. cruzi strains can differ considerably in different wildlife hosts.     

Seed dispersal by Japanese marten <Emphasis Type="Italic">Martes melampus</Emphasis> in the subalpine shrubland of northern Japan

The functions of carnivorous mammals as seed dispersers were studied during a snow-free period of 2 years in the subalpine shrubland of northern Japan. Mammal appearances, which were recorded using three automatic cameras, were dominated by Japanese marten, Martes melampus (Wagner), followed by three carnivores (ermine, red fox, and raccoon dog) and two other mammals (field mouse and Japanese hare). Fecal analysis revealed that the martens dispersed seeds of 11 species (eight woody and three herbaceous plants), which included a vine species that is an inhabitant of lower elevation sites. Fruit weight and size, and flesh weight and volume of the fleshy-fruited species foraged by the martens were significantly greater than those that were not foraged. These facts indicate that the marten plays a key role as a relatively long-distance seed disperser for major component species with large and flesh-rich fruits in the subalpine shrubland.     

Association of MC3R gene polymorphisms with body weight in the red fox and comparative gene organization in four canids

There are five genes encoding melanocortin receptors. Among canids, the genes have mainly been studied in the dog (MC1R, MC2R and MC4R). The MC4R gene has also been analysed in the red fox. In this report, we present a study of chromosome localization, comparative sequence analysis and polymorphism of the MC3R gene in the dog, red fox, arctic fox and Chinese raccoon dog. The gene was localized by FISH to the following chromosome: 24q24‐25 in the dog, 14p16 in the red fox, 18q13 in the arctic fox and NPP4p15 in the Chinese raccoon dog. A high identity level of the MC3R gene sequences was observed among the species, ranging from 96.0% (red fox – Chinese raccoon dog) to 99.5% (red fox – arctic fox). Altogether, eight polymorphic sites were found in the red fox, six in the Chinese raccoon dog and two in the dog, while the arctic fox appeared to be monomorphic. In addition, association of several polymorphisms with body weight was analysed in red foxes (the number of genotyped animals ranged from 319 to 379). Two polymorphisms in the red fox, i.e. a silent substitution c.957A>C and c.*185C>T in the 3′‐flanking sequence, showed a significant association (P < 0.01) with body weight.     

On the tryptic peptides from hemoglobin chains of six carnivores

Summary The amino acid compositions of the tryptic peptides of the following carnivore hemoglobin chains have been determined: gray fox (Urocyon cineroargenteus); raccoon (Procyon lotor); polar bear (Thalarctos maritimus); coati mundi (Nasua nasua) chain; coati mundi (Nasua narica) two chains; cat (Felis catus) chain; and lion (Panthera leo) chain. These provide a basis for future sequencing of these hemoglobins and construction of an evolutionary tree. The specific results are summarized in the following article (Stenzel and Brimhall, 1977).