Article 1. Berger and Gese (2007) examined whether spatial segregation limits the local distribution of coyotes by evaluating home-range overlap between resident coyotes and wolves. They also examined dispersal rates of captured transient coyotes in both wolf-free and wolf-abundant areas and analyzed data on the population densities of both species in the Greater Yellowstone Ecosystem (GYE) as well as gathering data on mortality and survival rates of coyotes in wolf-free and wolf-abundant sites at Grand Teton National Park (GTNP).
The main hypothesis tested by the researchers was that interference competition with wolves (canis lupus) limits the distribution and abundance of coyotes (canis latrans) and further that the extirpation of wolves is invoked as an explanation for the expansion of coyote ranges in North America. Based on this hypothesis, Berger and Gese (2007) predicted that coyotes would be the numerically predominant predator across the GYE while being substantially lower at wolf-abundant sites in GTNP.
The experimental method used included home range analysis and spatial segregation analysis, coyote captures in wolf-abundant and wolf-free sites, and the tracking of specific animals to identify survival rates and cause-specific mortality among coyotes and wolves. The data were collected from August 2001 to August 2004 from the two research sites to determine whether mortality due to wolves is sufficient to explain reduction in coyote densities. They evaluated home range overlap between the species and contrasted dispersal rates of transient coyotes captures in both wolf-free and wolf-abundant areas.
The statistical tests used to analyze the data included
indices of spatial segregation and the utilization distribution overlap index. Captured coyotes wee also assessed for health conditions and cause of death as were residents. The primary statistical test developed a Beta coefficient equal to - 3...