Postmortem Findings in Free-Ranging North American Beavers (Castor canadensis) Reveal Potential Threats to California’s Freshwater Ecosystems

Gonzales-Viera O.A.; Woods L.W.; Mete A.; Fritz H.; Armien A.G.; Lantz E.; Gomez-Puerta L.A.; Famini D.; Sherman J.; Rudd J.L.; Camp L.E.; Shapiro K.; Clifford D.L. · Animals (2025) · DOI: 10.3390/ani15030338

Resumen

Freshwater ecosystems are dynamic aquatic environments in which vegetation, wild and domestic animals, and humans constantly interact. Since beavers are semi-aquatic rodents that inhabit lakes, ponds, streams and rivers, we hypothesize that studying their diseases is a valuable parameter for understanding freshwater ecosystem health. Eighteen free-ranging beavers were included in this study, from which Baylisascaris spp.-associated or -suspected encephalitis was the main cause of death/reason for euthanasia, followed by bacterial infections with zoonotic potential like Staphylococcus aureus, Listeria monocytogenes, and Francisella tularensis, among others. Parasites such as Toxoplasma gondii, capillarid species, and Giardia spp. were the most important comorbidities in the beavers from California. Overall, beavers are exposed to several biological threats that can be transmitted to wild and domestic animals, as well as to humans, providing key data for understanding freshwater ecosystem health.

Instituciones: Universidad Nacional Mayor de San Marcos