A Serological Survey of Infectious Disease in Yellowstone National Park’s Canid Community

BACKGROUND:Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a >70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks. METHODOLOGY/PRINCIPAL FINDINGS:We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991-2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine parvovirus (wolf seroprevalence: 100%; coyote: 94%), canine adenovirus-1 (wolf pups [0.5-0.9 yr]: 91%, adults [>or=1 yr]: 96%; coyote juveniles [0.5-1.5 yrs]: 18%, adults [>or=1.6 yrs]: 83%), and canine herpesvirus (wolf: 87%; coyote juveniles: 23%, young adults [1.6-4.9 yrs]: 51%, old adults [>or=5 yrs]: 87%) suggesting that these pathogens were enzootic within YNP wolves and coyotes. An average of 50% of wolves exhibited exposure to the protozoan parasite, Neospora caninum, although individuals' odds of exposure tended to increase with age and was temporally variable. Wolf, coyote, and fox exposure to canine distemper virus (CDV) was temporally variable, with evidence for distinct multi-host outbreaks in 1999 and 2005, and perhaps a smaller, isolated outbreak among wolves in the interior of YNP in 2002. The years of high wolf-pup mortality in 1999 and 2005 in the northern region of the park were correlated with peaks in CDV seroprevalence, suggesting that CDV contributed to the observed mortality. CONCLUSIONS/SIGNIFICANCE:Of the pathogens we examined, none appear to jeopardize the long-term population of canids in YNP. However, CDV appears capable of causing short-term population declines. Additional information on how and where CDV is maintained and the frequency with which future epizootics might be expected might be useful for future management of the Northern Rocky Mountain wolf population

Inter-pack, seasonal and annual variation in prey consumed by wolves in Pollino National Park, southern Italy

Although understanding of food habits of wolves in human-modified landscapes is critical to inform conservation and conflict management, no such studies have ever been conducted in the southern Apennines, Italy, where wolves long coexisted with humans. By means of scat analysis (n = 1743) and log-linear modelling, we investigated diet composition in five wolf packs in the relatively simple prey system of the Pollino National Park (PNP), southern Italy (1999−2003). Overall, although wild boar was the most frequently consumed prey (mean frequency ± SD, 63.1 ± 23%), both wild boar and cattle predominated the diet in terms of biomass (45.3 ± 24 and 48.1 ± 21%, respectively). We revealed, however, a zonal (i.e. area, pack) followed by annual and seasonal effects on the wolf diet. Cattle consumption by wolf packs in the northern portion of PNP (Pollino subrange) was highest, especially during summer when cattle predominated the diet in terms of biomass (68.3 ± 20%). Instead, wild boar consumption was highest in the Orsomarso packs (biomass, 62.1 ± 13%), with increasing trends throughout the study period but no relevant seasonal variation. Wild boar piglets and cattle calves were the most frequently consumed age classes, revealing their availability year-round and higher profitability compared to other prey. Cattle consumption by wolves reflected prevailing husbandry techniques (free-ranging herds with unattended births) and determined a permanent state of conflict, often spurring retaliatory killing of wolves. Compatible cattle husbandry practices, along with the restoration of multi-prey communities, are needed to reduce wolf-livestock conflicts and possibly enhance the ecological role of wolves in human-altered ecosystems