Causes of Mortality and Factors Affecting Survival of Ruffed Grouse ('Bonasaumbellus') in Northern Michigan

摘要

The Michigan ruffed grouse (Bonasa umbellus) population has undergone a severedecline and during 1992-1993 was at an extremely low point in its current cycle, which began with a peak in 1989. The concerns of hunters, wildlife managers, and other conservationists about the diminishing numbers of grouse led to the initiation of the Michigan Ruffed Grouse Research Project in 1993. The goal of the study was to determine causes of mortality and survival rates for ruffed grouse. In addition, the effect of hunting on the grouse population was examined. Research was conducted on 2 study areas in the northeast lower peninsula of Michigan from May 1993 to August 1995. Each area was composed of 2 sites, one closed to hunting and one open to hunting under normal harvest regulations. Ruffed grouse were trapped from August to October 1993 and 1994 and fitted with radio collars equipped with 8-hour mortality sensors. Survival was monitored starting on the day after capture.