Survival, fall movements, and habitat use of hunted and non-hunted ruffed grouse in northern Michigan

The ruffed grouse (Bonasa umbellus) is pursed by approximately 130,000 hunters per year in Michigan. Hunters and wildlife biologists have many questions about the effects of hunting on grouse and how to better manage forests for this popular bird. This project takes a comprehensive five-year database (1993--1998) of fall grouse locations in sites open and closed to hunting and combines it with a habitat quality analysis to describe the characteristics of grouse behavior and survival in northern Michigan.; Ruffed grouse were radio-collared during the fall of each year in the Maltby Hills and Pigeon River study sites in Northern Michigan. Survival data were collected from August through May. In the first study season (1993--1994), ruffed grouse in the 2 sites closed to hunting had higher survival than did those in the 2 sites open to hunting. In all other years, survival in the sites open to hunting was comparable or higher than survival in the sites closed to hunting. In all sites, avian predation was the leading cause of mortality. In the open sites, hunting was generally the second leading cause of mortality, comprising 12--21 of known annual mortalities in the Maltby Hills site and 14--35% of known mortalities in the Pigeon River site.; Collared birds were located several times per week to measure fall activity range size and dispersal distances. Juvenile grouse tended to move longer distances and have larger activity ranges than did adult grouse. More females dispersed and they moved longer distances than did males. Activity range sizes were comparable to other studies in the Margaret E. Clark Northern United States, but dispersal distances in the Pigeon River were shorter than recorded elsewhere.; Habitat quality was assessed in each site using the HSI model for ruffed grouse in Michigan. Medium aged aspen (11--29 yr.) and lowland conifers ranked highest in cover quality, while upland hardwoods, oak, and old pine (>30 yr.) ranked lowest. The model's spatial variable, distance to aspen, dominated the model when applied on a landscape scale.; Using a geographic information system, habitat used (within activity ranges) was compared with habitat available, and habitat quality within activity ranges was compared to that within random circles. Ruffed grouse in the Maltby Hills study sites preferred young pine (0--29 yr.) and young aspen (0--10 yr.), and grouse in the Pigeon River sites preferred medium aged aspen (11--29 yr.) and jack pine. Birds in all sites avoided upland hardwoods. In all sites, non-dispersing grouse selected areas that had HSI scores higher than random. In 3 of the 4 sites, birds that chose high quality sites (according to the model) lived significantly longer than did birds that chose low quality sites.; The Cox Proportional Hazards model was used to evaluate the potential risks associated with various parameters. Juveniles had a higher risk of mortality than adults. The amount of young aspen within activity ranges positively affected survival in 3 of the 4 study sites, whereas in some cases, use of lowland areas and mature aspen negatively affected survival. This information can and should be used to improve ruffed grouse habitat modeling and management to ensure the future of this popular game bird.