Fall Foods of Sharp-Tailed Grouse in Minnesota

Abstract

The major September-October foods found in the crops of 263 sharp-tailed grouse (Pedioecetes phasianellus) shot in northern Minnesota were seeds of oats, wheat, flax, and Vaccinium sp.; leaves of clover (Trifolium spp); and grasshoppers. This paper presents data on foods found in the crops of 263 sharp-tailed grouse shot by hunters in 13 northern Minnesota counties in late September and early October, 1957. Most of the birds were shot on opening weekend, September 21-22 of the 1957 season. Some samples were collected by field personnel of the Minnesota Division of Game and Fish; others were sent in voluntarily by hunters along with wing and tail samples as part of a mail sex and age survey. The air-dried crop contents were placed in envelopes until an analysis could be made. Food items were measured volumetrically by water displacement. Although numerous authors have commented on the foods of sharp-tailed grouse, the results are often difficult to compare or interpret because methods have varied widely. Swanson (1940) based his conclusions on the analysis of 550 droppings. Marshall and Jensen (1937) and Hart et al. (1950) combined an examination of droppings with intensive field observations and an interpretation of other sign. Swenk and Selko (1938) examined the crops and gizzards of 29 birds, and Kobriger (1965) reported on fall foods found in 58 grouse crops from the sandhills of Nebraska. Aldous (1943) examined 19 gizzards and 6 crops from sharptails shot in the fall in North Dakota. Others have made general statements concerning sharp-tailed grouse food habits (Baumgartner 1939, Ammann 1957), and Hamerstrom and Hamerstrom (1951) generally summarized the food requirements of sharp-tailed grouse as they related to movements at all seasons. In Minnesota, the best sharp-tailed grouse range consists of a mixture of brushland, early forest, and agricultural types in the northern and northwestern portions of the state. The highest populations occur in the extreme northwestern counties and most of the crops were collected there. Thus, Kittson, Roseau, and Koochiching counties together contributed 168 of the 263 crops. Sixty-two crops were collected from seven other northwestern counties. In addition to the northwestern range, pockets of sharptailed grouse range occur in parts of several northeastern counties, but only 33 crops were collected from these areas; 20 from Aitkin County, 12 from Pine County, and 1 from St. Louis County. I am indebted to Gordon Gullion for providing me with examples of shrub buds and catkins. I am also indebted to various field personnel of the Minnesota Division of Game and Fish for providing samples. Much of the work was accomplished while I was employed by the Minnesota Division of Game and Fish on Pittman-Robertson project W-11-R. Plant names are from Fernald (1950).