Natural Resources Research Institute Technical Report

The Sandstone Unit of the Rice Lake National Wildlife refuge, located south of Sandstone, Minnesota (Pine County) was transferred to the U.S. Fish and Wildlife Service from the Bureau of Prisons, Department of Justice in 1970. The current Sandstone Unit boundary encompasses 2,045 acres, primarily upland and riparian hardwoods (Table 1). The United States Fish and Wildlife Service is in the process of developing a habitat management plan for the Sandstone Unit and have completed an environmental assessment (EA). Management alternatives indicated in the EA were: (1) conversion of 1,000 acres of forestland to grassland/brushland, (2.) conversion of 350 acres of forestland to grassland/brushland, and (3) forest management on the existing acreage to maintain representative mature forest types and grassland acreage. Current habitat management on the areas includes a haying permit to maintain grassland areas. The purpose of our research project was to identify bird species found in the Unit with special emphasis on determining the presence and abundance of forest and grassland passerines, raptors, and other species on the Fish and Wildlife Service or Minnesota Department of Natural Resources special concern lists [Coffin and Pfannmuller 1988]. These groups are worthy of special consideration because populations of many neotropical migrants (species that breed in North America and winter in Latin America or the Carribean) are declining on a national level [Robbins et al. 1989]. Species that have shown the greatest declines are those dependent on contiguous forests or large tracts of grassland. Although, causes of such declines are complex [Blake et al. 1992], forest fragmentation in breeding areas and deforestation in wintering areas are two major contributing factors [Terborgh 1989]. Breeding bird populations trends in Minnesota over the past 25 years do not reflect national level trends on a species specific basis (based on breeding bird surveys [Janssen 1990]) . However, these data are based on limited coverage of roadside counts (53 total) completed in the State. Our specific objectives for this project were to: (1) determine distribution, relative abundance, and species composition of birds in all habitats on the Sandstone Unit of the Rice Lake National Wildlife Refuge (NWR); (2) begin refining avian/habitat relationships used to assess forest management activities on breeding bird abundance and distribution in this area; and (3) integrate data gathered in the Sandstone Unit of the Rice Lake NWR with a large scale avian monitoring study to determine landscape level affects on bird species abundance and distribution in the State. Results of the study will add to our general knowledge of birds in northcentral Minnesota and will provide baseline data for comparison after a management plan has been implemented on the Unit