Home Range Characteristics of Ruffed Grouse Broods in Minnesota

Abstract

Home ranges of six ruffed grouse (Bonasa umbellus) broods in northeastern Minnesota were determined by radiotelemetry in 1964 and 1965. Mean size of the brood ranges was 12.9 ha, and average daily movement within the ranges was 376.8 m. The maximum distance of travel for a brood in one day was 966 m, with no movement occurring at night. Spatial overlap of two brood ranges took place, but occupancy of the area was at different times. Lowlands of moist soils, dominated by homogeneous stands of mature speckled alder (Alnus rugosa) and containing a diversity and profusion of ground layer vegetation, were utilized 63.6 percent of the time. Drier upland communities were utilized 13.4 percent of the tracking time, and stands of lowland conifer were used solely for roosting. Objective methods are used to describe the major habitat within the home ranges. Because the grouse population was at its lowest level in 12 years, the habitat occupied by these radio-tracked broods is considered quite representative of the community selected for brood range. J. WILDL. MANAGE. 39(2):287-298 Distribution of ruffed grouse broods in relation to plant communities is an inherently important aspect in the overall life history of this game bird. In reference to management implications, Bump et al. (1947:139) recognized this fundamental connection between a knowledge of brood [habitat] preferences and an increase in the grouse crop. Therefore, an accurate description of routinely selected brood areas should be available for any comprehensive evaluation of environmental factors possibly limiting population size and vitality in a given region. This study precisely delimits the home ranges utilized by specific grouse broods and describes the vegetative structure and composition of the habitat. It presents relevant ethoecological patterns associated with these findings, such as the accurate size of the brood ranges, travel within the areas, and the interrelationships of adjacent broods. I thank G. W. Gullion and W. H. Marshall for their counsel and support during this project, and B. A. Brown for making av i able the facilities of the Cloquet Forest Research Center. I am most grateful to B. M. Nelson, F. J. Svoboda, and R. O. Wallestad for their assistance both in the field and in processing data. This project was funded by National Science Foundation G ant GB-1345, the Minnesota Agricultural Experiment Station Project 17-83H, and Fed ral Aid to Wildlife Restoration Project W-35-R, Minnesota Department of Natural Resources.