Range expansion of coyotes, Canis latrans, threatens a remnant herd of caribou, Rangifer tarandus, in southeastern Quebec

Abstract

The autumn calf:cow ratio of a remnant caribou herd in Gaspesie Park, Quebec, declined from ≃20-30 calves per 100 females in 1984-1985 to only four in 1987, after coyotes colonized the area. In 1989 and 1990, 25 ratio-tagged calves were monitored and 26 of them died in the course of the summer. Likely cause of death was determined for 11 cases and suggested that coyotes were responsible for seven deaths. Predators were reduced in the park and surroundings between 1990 and 1992 in order to improve calf survival. Recruitment was sufficient to replace mortality after 1988 for the caribou group occupying the centre of the park, but it remained at about 10 calves:100 females until 1992 for the group inhabiting the E part of the park, at which time calf survival finally improved. -from Authors