Nutrition and behavior of striped skunks

Chlordane-Induced Neurotoxicosis in Urban and Suburban Detroit, Michigan Striped Skunks (Mephitis mephitis)

Despite the ban of technical chlordane, contamination from this persistent organic pollutant has threatened wildlife and human health nearly forty years since its last application. The purpose of this study is to highlight the need for more systemic, broad-scale research efforts to monitor technical chlordane in wildlife sentinel species in urban settings to understand the nature and extent of pesticide pollution and mitigate risk associated with exposure to these compounds. This study presents an unusual finding of neurotoxicosis and elevated chlordane metabolite concentrations in Michigan striped skunks in the absence of other viral or toxic etiologies. In this study, eight of seventeen skunks displaying illness and neurologic signs had brain tissue concentrations of combined oxychlordane, heptachlor epoxide, and trans-nonachlor exceeding the 1000 ng/g wet weight diagnostic threshold for toxicosis. Liver tissue concentrations were ten-fold greater than those of the brain when measured on a lipid weight basis, which can help predict lethal brain residues in skunks. The ongoing presence of chlordane in the environment is expected to cause further unintended consequences for wildlife across the Detroit Metropolitan Area for decades to come. Together, veterinary toxicologists, wildlife biologists, environmental toxicologists, ecologists, and policy makers must utilize a One Health transdisciplinary approach and continue to evaluate the long-term effects of chlordane exposure. As with other pollutants in the River Rouge and River Raisin Areas of Concern, the presence of chlordane in the urban environment presents a significant risk for animal, human, and ecological health.

Patterns of striped skunk scavenging on human remains

Scavenging is a known behavior of striped skunks (Mephitis mephitis), though it is rarely documented. Striped skunks were observed and documented scavenging nine human donors at the Forensic Investigation Research Station (FIRS) in Whitewater, Colorado from October 2017 through September 2019. Human remains are placed on the surface, outdoors, in a fenced area, and monitored daily through notes, photographs, and multiple systems for scoring decomposition. Motion-activated game cameras are strategically positioned to monitor potential scavenger activity within the facility. When scavenging occurred, game camera images were temporally correlated to daily photographs and notes to confirm the source of observed defects. Striped skunks at the FIRS scavenged the soft tissue of the arms, legs, genitals, and torso. Game camera images documented skunks digging, climbing on top of remains, repositioning limbs, and using their paws to manipulate tissue. These activities impacted soft tissue, bone, and the surrounding environment. Scavenging patterns varied seasonally, with higher frequency and lower selectivity in the winter. Striped skunks are common throughout most of North America and are likely to scavenge human remains when available. Understanding patterns and behaviors of specific scavengers can help investigators accurately interpret defects found on and around human remains.

Beyond the raccoon roundworm: The natural history of non-raccoon Baylisascaris species in the New World

A total of 10 species of Baylisascaris, a genus of ascaridoid nematodes, occur worldwide and 6 of them occur in the New World. Most of the Baylisascaris species have a similar life cycle with carnivorous mammals or marsupials serving as definitive hosts and a smaller prey host serving as paratenic (or intermediate) hosts. However, one species in rodents is unique in that it only has one host. Considerable research has been conducted on B. procyonis, the raccoon roundworm, as it is a well-known cause of severe to fatal neurologic disease in humans and many wildlife species. However, other Baylisascaris species could cause larva migrans but research on them is limited in comparison. In addition to concerns related to the potential impacts of larva migrans on potential paratenic hosts, there are many questions about the geographic ranges, definitive and paratenic host diversity, and general ecology of these non-raccoon Baylisascaris species. Here, we provide a comprehensive review of the current knowledge of New World Baylisascaris species, including B. columnaris of skunks, B. transfuga and B. venezuelensis of bears, B. laevis of sciurids, B. devosi of gulonids, B. melis of badgers, and B. potosis of kinkajou. Discussed are what is known regarding the morphology, host range, geographic distribution, ecoepidemiology, infection dynamics in definitive and paratenic hosts, treatment, and control of these under-studied species. Also, we discuss the currently used molecular tools used to investigate this group of parasites. Because of morphologic similarities among larval stages of sympatric Baylisascaris species, these molecular tools should provide critical insight into these poorly-understood areas, especially paratenic and definitive host diversity and the possible risk these parasites pose to the health to the former group. This, paired with traditional experimental infections, morphological analysis, and field surveys will lead to a greater understanding of this interesting and important nematode genus.