Canada lynx live in moist boreal forest areas in the U.S. and Canada. Due to the patchiness of boreal forest in the U.S., there is a lower density of lynx compared to that of lynx populations in the forests of Canada. Since 1997, the lynx has been a species of Special Concern to the Maine Department of Inland Fisheries and Wildlife (MDIFW) and has been federally listed as Threatened since 2000. Once considered “irregular and anecdotal,” the population of lynx in Maine has been increasing since the late 1990s in response to the abundance of high quality habitat for lynx and their main prey, snowshoe hares. In 1999, six lynx were radio collared and results indicated that there was, in fact, a resident population of lynx in Maine. Over the next 10 years, another 79 lynx were equipped with radio collars to help assess the status of lynx in Maine. Since 2000, biologists have been collecting lynx carcasses to identify potential causes of mortality. Initial work by diagnosticians at the University of Maine found evidence of lungworm as factor contributing to the mortality of lynx that were emaciated. Recently, NWDC began working with biologists at MDIFW to conduct a mortality study in collaboration with diagnosticians at New Hampshire Veterinary Diagnostic Laboratory to build on the work initiated at the University of Maine. Specifically, we are: 1) looking for lesions (primarily lungworm), 2) assessing some nutritional factors, 3) assessing (qualitatively) enteric parasite colonization, 4) attempting to find a gamma herpes virus, and 5) caching frozen tissue samples.