Didelphis Virginiana Research Articles

Sarcocystis neurona schizonts-associated encephalitis, chorioretinitis, and myositis in a two-month-old dog simulating toxoplasmosis, and presence of mature sarcocysts in muscles

Sarcocystis neurona is an unusual species of the genus Sarcocystis. Opossums (Didelphis virginianus, D. albiventris) are the definitive hosts and several other species, including dogs, cats, marine mammals, and horses are intermediate or aberrant hosts. Sarcocysts are not known to form in aberrant hosts. Sarcocystis neurona causes fatal disease in horses (Equine Protozoal Myeloencephalitis, EPM). There are numerous reports of fatal EPM-like infections in other species, usually with central nervous system signs and associated with the schizont stage of S. neurona. Here, we report fatal disseminated S. neurona infection in a nine-week-old golden retriever dog from Mississippi, USA. Protozoal merozoites were identified in smears of the cerebrospinal fluid. Microscopically, lesions and protozoa were identified in eyes, tongue, heart, liver, intestines, nasal turbinates, skeletal muscle and brain, which reacted intensely with S. neurona polyclonal antibodies. Mature sarcocysts were seen in sections of muscles. These sarcocysts were ultrastructurally similar to those of S. neurona from experimentally infected animals. These data suggest that the dog is another intermediate host for S. neurona. Data suggest that the dog was transplacentally infected.

Artificial Nests Identify Possible Nest Predators of Eastern Wild Turkeys

Poor nest survival is a critical limiting factor in the recruitment of wild birds. Nest predation is often cited as one of the main causes of nest failure, especially for ground-nesting species. We monitored artificial Meleagris gallopavo silvestris (Eastern Wild Turkey) nests, using time-lapse and motion-sensitive trail cameras to determine which predators were likely to be responsible for preying on Wild Turkey nests in the Pineywoods of East Texas. Sixty-one percent of all artificial nests were preyed upon. Corvus brachyrhynchos (American Crow) preyed on 48% of artificial nests and Procyon lotor (Raccoon) preyed on 35%. There was a seasonal increase in the number of artificial nests preyed upon from spring to summer. Mammalian mesopredators, Raccoon and Didelphis virginiana (Opossum), were primarily responsible for this increase, suggesting an increase in search effort by mesopredators that coincided with increased dietary diversity in a period of reduced prey resources. Predators other than mesopredators—American Crows, Picoides sp. (woodpeckers), Dasypus novemcinctus (Nine-banded Armadillo), and snakes—were responsible for 53% of all predation on the artificial Wild Turkey nests, with American Crows being the most important of these. After nest deployment, American Crows located and preyed on artificial nests more quickly than other nest predators. We suggest video monitoring of natural Eastern Wild Turkey nests to confirm the identity of nest predators.

Application of GIS to a Baseline Survey of Vertebrate Roadkills in Baldwin County, Georgia

Physical attributes, traffic volume, and landscape patterns on a particular road are expected to influence the frequency of vertebrate road fatalities. In this study, we surveyed 22.17 km of roadways in Baldwin County, GA, 171 times (3791.1 km total) for vertebrate roadkills over a calendar year. We coded the survey route—consisting of portions of US Highway 441, G A Highway 212, and Meriwether/Lowe Road—for differing habitat types and obstacles along its length, and mapped the spatial data in ArcGIS. We recorded 178 vertebrate roadkills representing 19 species, primarily mammals, with Odocoileus virginianus (White-tailed Deer; n = 46) and Didelphis virginiana (Virginia Opossum; n = 39) most frequently observed. We calculated a roadkill rate of 8.03/km/yr. US 441, which has the most lanes, highest traffic volume, and greatest verge width, had the highest roadkill rate (10.95/km/yr) of the three sections. Seasonal differences in roadkill frequencies for the most commonly observed species appear to be related to periods of mating or dispersal.

Spontaneous Cure after Natural Infection with Gnathostoma turgidum (Nematoda) in Virginia Opossums (Didelphis virginiana)

Seasonality of the nematode Gnathostoma turgidum in Virginia opossums (Didelphis virginiana) in the wild has been reported; however, the mechanisms involved in deworming are unknown. We monitored the parasitologic and biologic changes in four Virginia opossums naturally infected with G. turgidum by coproparasitologic examination and abdominal ultrasonography. Eggs became detectable in the feces of opossums in May, peaked in July and August, and suddenly decreased in October. Adults of G. turgidum were expelled in the feces mainly in September. Ultrasonography of the liver showed slight damage during May. Lesions in the stomach appeared in April and persisted until September. The abnormalities of the liver and stomach were resolved in November. These data suggest that G. turgidum is likely expelled as a result of host immunologic mechanisms, although termination of a natural life span cannot be definitively excluded.

Using Infrared-Triggered Cameras to Monitor Activity of Forest Carnivores

The activity patterns of 4 forest predator species were monitored, using infrared-triggered cameras, within a 1318-ha study area in East Texas. We recorded 161 photographic capture events in 1925 trap-nights over 17 weeks. Photographic capture events included 18 Lynx rufus (Bobcat), 109 Procyon lotor (Raccoon), 21 Didelphis virginiana (Virginia Opossum), and 13 Canis latrans (Coyote). We developed an easily replicated method of measuring time on a percent scale to compare activity data over several months, accounting for changes in sunrise and sunset times. Bobcat activity was 38.9% crepuscular and 22.1% diurnal. The activity of the other 3 species was mostly nocturnal: Raccoon 94.5%, Virginia Opossum 100%, and Coyote 77%. Moon phase based on percentage of visible light did not affect either Raccoon or Virginia Opossum nocturnal activity level.

Redescription ofOligacanthorhynchus microcephalus(Rudolphi, 1819) Schmidt 1972 (syn.Oligacanthorhynchus tortuosa(Leidy, 1850) Schmidt 1972) (Acanthocephala: Oligacanthorhynchidae)

Oligacanthorhynchus microcephalus (Rudolphi, 1819) Schmidt, 1972 was originally described from the philander opossum Caluromys philander from Brazil. Oligacanthorhynchus tortuosa (Leidy, 1850) Schmidt, 1972 was originally described from the Virginia opossum (Didelphis virginiana) in North America. Six years after describing O. tortuosa, Leidy indicated the synonomy of O. tortuosa with O. microcephalus. This taxonomic view persisted for decades until Van Cleave, in 1924, recognized the validity of O. tortuosa, apparently without examining the type material of O. microcephalus. Subsequent workers have recognized 2 species of Oligacanthorhynchus from New World opossums: O. microcephalus from South American opossums and O. tortuosa from North American opossums. In this study, comparison of individuals of O. tortuosa from D. virginiana from the United States with the type specimen of O. microcephalus revealed the worms to be conspecific. It was thus determined that O. tortuosa is a junior synonym of O. microcephalus and O. microcephalus is redescribed on the basis of both laboratory-reared material and the type specimen. Additionally, comparison of the type material of Oligacanthorhyncus tumida (Van Cleave, 1947) Schmidt, 1972 revealed these specimens to be conspecific with O. microcephalus; thus O. tumida (Van Cleave, 1947) Schmidt, 1972 is considered a junior synonym of O. microcephalus. Analysis of the literature and museum specimens reveals that O. microcephalus exhibits a broad distribution throughout much of the New World, utilizing an array of hosts with substantially overlapping ranges.

Habitat selection by a generalist mesopredator near its historical range boundary

The Virginia opossum (Didelphis virginiana Kerr, 1792) has expanded its geographic range northward since European settlement, which has been attributed to its ability to exploit anthropogenic resources. To examine the utility of anthropogenic resources to this species, we monitored 61 opossums from 2009 to 2010 with very high frequency (VHF) telemetry in a fragmented agricultural ecosystem in northern Indiana, USA, at the periphery of the opossum’s historical distribution. We examined the influence of anthropogenic (agricultural areas, developed land, roads), disturbed (corridor, forest edge, grassland, water), and native (forest, shrub land) habitats on habitat selection at the second- and third-order scales across three seasons. At the second-order scale, areas proximate to agricultural fields and developed land were selected in the breeding and postbreeding seasons, respectively. Areas proximate to roads were selected at both spatial scales during all seasons except winter at the third-order scale. Areas near forest with high forest-edge density were selected throughout the year at both spatial scales, but confidence intervals for forest during the postbreeding season marginally overlapped zero (third-order scale). Although anthropogenic habitats provide novel resources for opossums, forest and forest edge remain essential components to populations near their historical distributional limit in agricultural ecosystems.

The Conflicting Roles of Vector Control and Animal Control Agencies in Mitigating the Rise of Human Cases of Flea-borne Typhus in Orange County, California

Flea-borne typhus has emerged as an important vector-borne disease in Los Angeles and Orange Counties, California, with over 400 human cases having been reported since the mid-1980s. In Orange County alone, 127 human cases have been investigated by the Orange County Vector Control District since 2006. Results from a collaborative study with the Centers for Disease Control and Prevention from 2006-2008 identified the suburban cycle of flea-borne typhus transmission (backyard wildlife/pets – fleas – humans) in Los Angeles and Orange counties. Free-ranging feral and companion cats and the Virginia opossum were identified as the primary host animals of the cat flea, the insect vector responsible for maintenance and transmission of the etiologic agents, Rickettsia typhi and R. felis, for disease in humans. Although the causes of the increase in human flea-borne typhus cases are not well-defined, this rise has been accompanied by changes in how public and privately-sponsored animal control groups manage nuisance animal populations in the affected southern California counties. Instead of elimination through euthanasia of unwanted feral cats and non-native opossums, rehabilitation, relocation, and “no-trap” policies have become the preferred practice of local animal control agencies. The public health obligation for which governmental animal control agencies were created must be re-emphasized as one way of preventing further outbreaks of flea-borne typhus infections in Orange County and the surrounding California counties.

Opossum Nematodiasis: Diagnosis and Treatment of Stomach, Intestine, and Lung Nematodes in the Virginia Opossum (Didelphis virginiana)

Internal parasitic infections are common in the Virginia opossum (Didelphis virginiana). More than 50 different species of nematodes have been identified from the genus Didelphis. Of them, 3 can cause significant illness to native opossums in Southern California, 2 gastrointestinal nematodes and 1 pulmonary nematode. This article provides an overview of the life cycles, methods for identification, pathologic findings, diagnostic tests, clinical signs, and options for treating these common nematode species.

Mammalian Depredation of Artificial Alligator Snapping Turtle (Macrochelys temminckii) Nests in North Louisiana

Nest depredation is a major source of mortality in many turtle populations. Although turtle life histories may have evolved with relatively high levels of nest depredation, present-day levels may be negatively impacting populations that are already declining. This degree of depredation may be problematic for species such as Macrochelys temminckii (Alligator Snapping Turtle), which has relatively low reproductive output for a large turtle, yet little is known about depredation of M. temminckii nests. We constructed 90 artificial M. temminckii nests in 2008 and 2009 at Black Bayou Lake National Wildlife Refuge in Louisiana to identify nest predators and elucidate patterns of nest depredation. All artificial nests were depredated, with Procyon lotor (Raccoon), and Dasypus novemcinctus (Nine-banded Armadillo) being the two most common nest predators. Other predators included Lontra canadensis (Northern River Otter), Didelphis virginiana (Virginia Opossum), and Lynx rufus (Bobcat). Nest depredation is a major threat to Alligator Snapping Turtles at this site and may be limiting recruitment in this population.

Management of raccoon roundworm in free‐ranging raccoon populations via anthelmintic baiting

ABSTRACTRaccoon roundworm (Baylisascaris procyonis), a common gastrointestinal parasite of the raccoon (Procyon lotor), has been implicated in population declines of Allegheny woodrats (Neotoma magister). Medicinal baiting is a viable tool in wildlife disease management although unique challenges exist for pathogenic systems in which the host can be immediately re‐infected following treatment. Our goals were to evaluate the efficacy of using monthly distribution of anthelmintic baits to reduce the prevalence of B. procyonis infection in raccoons and to quantify patterns and rates of bait acceptance among populations repeatedly exposed to medicinal baits. We distributed baits monthly at a density of 200/km2 throughout 300‐m buffer areas surrounding woodrat habitats in Indiana. We conducted raccoon latrine surveys annually to quantify the effect of treatment on roundworm prevalence and used remote cameras to identify the species contacting baits and determine the rate at which baits were removed. We observed declines in B. procyonis prevalence in response to treatment, but our ability to resolve statistical differences was limited by low pretreatment prevalence and high annual variability. Baits were removed rapidly from camera stations with 60% taken within 24 hours, 80% within 48 hours, and 90% within 72 hours. Virginia opossums (Didelphis virginiana) removed 51% of baits whereas raccoons removed 44%. Identification of opossums as the predominant consumer of baits emphasizes the limitations imposed by non‐target bait consumption for mitigation of B. procyonis and other wildlife diseases. The rapid removal of baits despite repeated bait exposure suggests that habituation did not result in bait aversion and fishmeal baits are a viable delivery system for mitigation of raccoon‐borne diseases requiring repeated treatments. Similar treatment measures may facilitate conservation of Allegheny woodrats in habitats with high rates of B. procyonis‐related mortality and could be used to reduce human exposure to this zoonotic parasite. © 2013 The Wildlife Society.

Isolation of deer tick virus (Powassan virus, lineage II) from Ixodes scapularis and detection of antibody in vertebrate hosts sampled in the Hudson Valley, New York State

BackgroundDeer tick virus, DTV, is a genetically and ecologically distinct lineage of Powassan virus (POWV) also known as lineage II POWV. Human incidence of POW encephalitis has increased in the last 15 years potentially due to the emergence of DTV, particularly in the Hudson Valley of New York State. We initiated an extensive sampling campaign to determine whether POWV was extant throughout the Hudson Valley in tick vectors and/or vertebrate hosts.MethodsMore than 13,000 ticks were collected from hosts or vegetation and tested for the presence of DTV using molecular and virus isolation techniques. Vertebrate hosts of Ixodes scapularis (black-legged tick) were trapped (mammals) or netted (birds) and blood samples analyzed for the presence of neutralizing antibodies to POWV. Maximum likelihood estimates (MLE) were calculated to determine infection rates in ticks at each study site.ResultsEvidence of DTV was identified each year from 2007 to 2012, in nymphal and adult I. scapularis collected from the Hudson Valley. 58 tick pools were positive for virus and/or RNA. Infection rates were higher in adult ticks collected from areas east of the Hudson River. MLE limits ranged from 0.2-6.0 infected adults per 100 at sites where DTV was detected. Virginia opossums, striped skunks and raccoons were the source of infected nymphal ticks collected as replete larvae. Serologic evidence of POWV infection was detected in woodchucks (4/6), an opossum (1/6), and birds (4/727). Lineage I, prototype POWV, was not detected.ConclusionsThese data demonstrate widespread enzootic transmission of DTV throughout the Hudson Valley, in particular areas east of the river. High infection rates were detected in counties where recent POW encephalitis cases have been identified, supporting the hypothesis that lineage II POWV, DTV, is responsible for these human infections.

The safety of ONRAB® in select non-target wildlife

ONRAB® is a recombinant human adenovirus type 5 (HAd5) with the rabies glycoprotein gene incorporated into its genome. ONRAB® has been used in Canada as an oral rabies vaccine in target wildlife species such as: red fox (Vulpes vulpes), raccoon (Procyon lotor), and striped skunk (Mepthis mephitis). We evaluated the safety of ONRAB® in non-target wildlife species likely to contact the vaccine baits during oral rabies vaccine campaigns in the United States. We investigated the effects of oral inoculation of high titer ONRAB®, approximately ten times the dose given to target species, in wood rats (Neotoma spp.), eastern cottontail rabbits (Sylvilagus floridanus), Virginia opossums (Didelphis virginiana), eastern wild turkeys (Meleagris gallopavo silvestri), and fox squirrels (Sciurus niger). We performed real-time polymerase chain reaction (PCR) on fecal swabs, oral swabs, and tissues, including lung, liver, kidney, small intestine, large intestine, and when appropriate nasal turbinates, to detect ONRAB® DNA from inoculated animals. By seven days post-inoculation, turkeys, opossums, and cottontails had all stopped shedding ONRAB® DNA. One wood rat and one fox squirrel still had detectable levels of ONRAB® DNA in fecal swabs 14 days post-inoculation. Real-time PCR analysis of the tissues revealed some ONRAB® DNA persisting in certain tissues; however, there were no significant gross or histologic lesions associated with ONRAB® in any of the species studied. Our results suggest that many non-target species are not likely to be impacted by the distribution of ONRAB® as part of oral rabies vaccination programs in the United States.

First Record of Scavenging by a Western Screech-Owl (Megascops kennicottii)

Scavenging is a common behavior in many animal species and can increase the fitness of individuals and populations. Scavenging has been documented more commonly in recent years with advances in technology, including in difficult to observe avian species. Four North American owl species have been documented scavenging, and here we relate the first documented scavenging by a Western Screech-Owl (Megascops kennicottii), which was video-documented with a motion-triggered camera. The screech-owl visited a Virginia Opossum (Didelphus virginiana) carcass seven times over an 11-hr period, with the longest visit lasting 7 mins (mean = 3.14 ± SD 2.34 mins); during the visits the owl actively fed on the carcass. The most common prey of Western Screech-Owls are small mammals, insects, arthropods, and small birds. No mesocarnivore or large mammal has ever been detected in diet studies of screech-owls, though screech-owls have been shown to attack and kill prey larger than themselves. The importance of carrion in owl diets is largely unexplored, and the scavenging behavior of owls could be more significant than currently believed depending on its availability and the presence of competing scavengers. Further research is needed to establish the commonality of scavenging by owls, and its various ecological effects.

Wildlife Contact Rates at Artificial Feeding Sites in Texas

Given the popularity of feeding white-tailed deer (Odocoileus virginianus) in Texas and the increasing amount of corn that is distributed, more information is needed on the impacts of this activity on non-target wildlife. Our objectives were to report visitation, intra- and interspecific contact, and contact rates of wildlife at artificial feeding sites in Texas. Our study was conducted at three sites in Kleberg and Nueces counties, Texas. We trapped animals from February to April and August to September, 2009 and marked animals with passive integrated transponder (PIT) tags. At each site and season, we placed one feeder system containing a PIT tag reader within 600 m of trap locations. Readers detected PIT tags from a distance of 25 cm. We determined a contact event to occur when two different PIT tags were detected by feeder systems within 5 s. We recorded 62,719 passes by raccoons (Procyon lotor), 103,512 passes by collared peccaries (Pecari tajacu), 2,923 passes by feral swine (Sus scrofa), 1,336 passes by fox squirrels (Sciurus niger), and no passes by opossums (Didelphis virginiana) at feeder systems. For site-season combinations in which contact events occurred, we found intraspecific contact rates (contacts per day) for raccoons, collared peccaries, and feral swine to be 0.81-124.77, 0.69-38.08, and 0.0-0.66, respectively. Throughout our study we distributed ~2,625 kg of whole kernel corn, which resulted in 6,351 contact events between marked wildlife (2.4 contacts per kg of corn). If 136 million kg of corn is distributed in Texas annually, we would expect >5.2 billion unnatural contact events between wildlife would result from this activity each year in Texas. Consequently, we do not believe that it is wise for natural resource managers to maintain artificial feeding sites for white-tailed deer or other wildlife due to pathogen transmission risks.

How Kitty is Killing the Dolphins

The article discusses the ecological impact of the spread of pathogens from land animals to marine animals. Topics include a parasite found in domestic cats, called Toxoplasma gondii, that has sickened dolphins found stranded in the Mediterranean Sea, research by wildlife pathologist and veterinarian Melissa A. Miller and colleagues that found California sea otters were being infected by a parasite carried by the Virginia opossum, called Sarcocystis neurona, the impact of drug-resistant bacteria on marine animals, and the need for better wastewater purification techniques and the expansion of wetlands that buffer land from sea.

Surveillance and movements of Virginia opossum (Didelphis virginiana) in the bovine tuberculosis region of Michigan

Wildlife reservoir hosts of bovine tuberculosis (bTB) include Eurasian badgers (Meles meles) and brushtail possum (Trichosurus vulpecula) in the UK and New Zealand, respectively. Similar species warrant further investigation in the northern lower peninsula of Michigan, USA due to the continued presence of bTB on cattle farms. Most research in Michigan, USA has focused on interactions between white-tailed deer (Odocoileus virginianus) and cattle (Bos taurus) for the transmission of the infectious agent of bTB, Mycobacterium bovis, due to high deer densities and feeding practices. However, limited data are available on medium-sized mammals such as Virginia opossum (Didelphis virginiana; hereafter referred to as opossum) and their movements and home range in Michigan near cattle farms. We conducted surveillance of medium-sized mammals on previously depopulated cattle farms for presence of M. bovis infections and equipped opossum with Global Positioning System (GPS) technology to assess potential differences in home range between farms inside and outside the bTB core area that has had cattle test positive for M. bovis. On farms inside the bTB core area, prevalence in opossum was comparable [6%, 95% confidence interval (CI) 2.0-11.0] to prevalence in raccoon (Procyon lotor; 4%, 95% CI 1.0-9.0, P=0.439) whereas only a single opossum tested positive for M. bovis on farms outside the bTB core area. The prevalence in opossum occupying farms that had cattle test positive for M. bovis was higher (6.4%) than for opossum occupying farms that never had cattle test positive for M. bovis (0.9%, P=0.01). Mean size of home range for 50% and 95% estimates were similar by sex (P=0.791) both inside or outside the bTB core area (P=0.218). Although surveillance efforts and home range were not assessed on the same farms, opossum use of farms near structures was apparent as was selection for farms over surrounding forested habitats. The use of farms, stored feed, and structures by opossum, their ability to serve as vectors of M. bovis, and their propensity to ingest contaminated sources of M. bovis requires additional research in Michigan, USA.

Simple method for locating a suitable venipuncture site on the tail of the Virginia opossum (Didelphis virginiana)

We identified a site suitable for venipuncture on the tail of the Virginia opossum (Didelphis virginiana) that is reliably and easily located. The prominent hemal arch associated with the ventral surface of caudal vertebra 5 serves as an easily palpated anatomical landmark for locating the ventral caudal vein for blood collection. Because this venipuncture site is only thinly covered by fur and visualization of the vein is not necessary for its location, site preparation and total animal handling time for routine venipuncture are minimal. Blood may be collected from immature and adult male and female animals, and the technique is easily taught to new technicians with minimal danger of injury to the animal.

Trypanosoma cruzi Infection in Didelphis virginiana in Relation to Population Parameters and Variables Associated with Presence in Rural Community Dwellings in Yucatan, Mexico

Facultad de Medicina Veterinaria y Zootecnia, Campus de Ciencias Biologicas y Agropecuarias, Universidad Autonoma de Yucatan, km 15.5 carretera Merida-Xmatkuil. Apdo. Postal 4-116 Itzimna, Merida, Yucatan, Mexico Laboratorio de Zoonosis y otras ETV’s, Centro de Investigaciones Regionales ‘‘Dr. Hideyo Noguchi’’, Universidad Autonoma de Yucatan, Av. Itzaes #490 9 59, Col. Centro, C.P. 97000 Merida, Yucatan, Mexico Facultad de Matematicas, Universidad Autonoma de Yucatan, Periferico Norte Tablaje 13615 A.P. 172, C.P. 97119 Merida, Yucatan, Mexico

Role of free-ranging mammals in the deposition of Escherichia coli into a Texas floodplain

Context The role of wildlife in faecal pollution of water bodies (deposition of Escherichia coli (E. coli)) is not well understood. Current water-quality and land-use planning research largely relies on unreliable wildlife data (e.g. poor sourcing of abundance estimates, population density estimates applied to multiple fundamentally different areas, suspect or insufficiently described data collection techniques) Aims Our goal for the present research was to investigate deposition of E. coli into a floodplain by free-ranging mammals. Objectives of the research were to determine the density of important free-ranging meso- and large mammals in the study area, determine faecal E. coli loads for each species, and evaluate spatial data on species-specific faecal deposition. Methods We conducted our research in south-eastern Texas, USA, on two cattle ranches bisected by Cedar Creek (44-km long). Cedar Creek has elevated E. coli concentrations. We conducted mark–recapture and mark–resight population density estimates (2008/09) for meso- and large mammals in the study areas. We collected faecal samples from all captured wildlife. We also conducted transects through the study area to determine faecal-deposition patterns. Key results We found that raccoons (Procyon lotor), wild pigs (Sus scrofa), Virginia opossums (Didelphis virginiana) and white-tailed deer (Odocoileus virginianus) all had substantial faecal E. coli loads and population densities, thus implying an important role in E. coli deposition into the study floodplain. All species were widely distributed through the floodplain. Conclusions Free-ranging mammals contribute E. coli to floodplains and potentially affect water quality. We determined that four species commonly found in floodplains throughout North America all contributed E. coli to the study floodplain, thus implying mammal E. coli contributions in many locations and this is potentially important for E. coli management. Implications Improved locally specific mammal population estimates and estimates of locally derived E. coli concentration will improve floodplain and water-quality models that often depend on data of various quality. Additionally, our analyses demonstrated the need for continued research into the role of wildlife in E. coli deposition.