Northern Prairie Wildlife Research Center
Not many hunters take advantage of North Dakota's short, three-day sage grouse season, which is confined to the southwestern-most corner of the state. But some hunters see this large native upland game bird as a trophy, and pursue them every year. Veteran sage grouse hunters can often identify adult male birds on the wing.
Adult male sage grouse are often found alone or in small groups during the mid-September season. At the same time, hens are usually still with their broods.
If you put an adult hen and an adult male sage grouse side-by-side, the male is the bigger one. However, size comparison is not often available, so you need to look at feathers to determine sex.
The key feathers for determining sex of sage grouse are found under the tail. These feathers are black with white tips, but the female feathers differ from those of the male.
|The feathers that can tell you whether a sage grouse is a male or female are found underneath the tail. The white rachis or spine on the black feathers with white tips indicates this bird is a female.|
The photo below shows feathers from the underside of the tail of male and female sage grouse. The male feather is all black, with a solid white tip. The rachis or spine of the female feather is white. In addition, the female feather also has white or buff-colored specks in the black area.
|A closeup of feathers taken from the underside of male and female sage grouse tails. The male feather, solid black with a white tip, is on the left. The female feather on the right has a white rachis or spine, and some additional buff-colored markings.|
One way to age sage grouse, according to Jerry Kobriger, is the pointedness of the tips of the number eight, nine and 10 primary wing feathers. The photos in the "Some Basics" section of this guide show a good example of juvenile and adult wing feathers. The juvenile primaries are narrow and more pointed when compared to the adult primaries. In addition, the ends of the juvenile primaries are frayed, while the adult primary ends are smooth.
The molt of the primaries can also be a good indicator of age. If the outer two primaries, number nine and 10, are growing (see photo in "Some Basics" section), the bird is likely an adult. If the number seven or eight primary is growing, or is missing (which means they are molted and haven't started growing), the bird is likely a juvenile.
The sage grouse season runs for only three days. During that time in mid-September, both juvenile and adult birds can exhibit a variety of stages of molt, Kobriger says.