The distribution of pathogens and their impact on the population dynamics of wildlife are areas of increasing interest in the ecological and conservation communities. Mammalian carnivores may be especially vulnerable to the effects of disease because they are rare, have complex social interactions, and are closely related to two domestic species, dogs and cats, which are subsidized by humans and thus live at high densities. We know that disease outbreaks in carnivore populations have sometimes resulted in measurable population declines and extinctions, but we don't know how commonly this occurs and how much effort should be exerted to prevent it. In many regions, we cannot assess the risk of disease spillover, as data on baseline levels of disease exposure do not exist. In an attempt to address these issues, this study will investigate the disease ecology of carnivores in the Chaco, a tropical dry forest in South America.
Despite the arid climate, the Chaco of Bolivia has a surprising diversity of carnivores. It is home to numerous threatened and endangered felids, including jaguars, ocelots, margays, and Geoffroy's cats. Kaa-Iya del Gran Chaco National Park, a large protected area in Bolivia, was established to safeguard these species, as well as other fauna such as the endemic Chacoan (or giant) peccary. The Park is contiguous with an indigenous territory that is titled to the Izoceno people. The Izocenos use this area extensively for hunting and resource extraction, and nearly all hunting involves dogs. This means that hunting dogs are entering the forest along the border of the park on a daily basis. Our goals with this project are to identify which diseases are present in the hunting dog population, quantify the opportunities that exist for contact between dogs and wild carnivores, and determine if wild carnivores living in the buffer zone surrounding the park are more likely to have been exposed to disease than those living inside the park.
Working with Bolivian biologists and indigenous parabiologists, we are sampling domestic dogs and wild carnivores in the Izoceno communities, in the buffer zone, and inside the park. In addition, we are conducting interviews with the Izocenos to learn more about hunting dog demographics and ecology. We want to ascertain how often dogs enter the forest, where they go, and how long they stay there. We are also trying to get basic information about how long dogs live, how they die, and the turnover of the population. Preliminary data show that these dogs have a short lifespan, and a very high neonatal mortality rate. We are also collecting information about diseases that can be transmitted to humans. Our hope is that this project will ultimately allow us to make recommendations that will improve the health of the hunting dogs, improve the health of the humans, and protect the health of the wildlife.
