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Upland Game Identification

A Basic Guide for Aging and Sexing the Bird in Your Hand

Photo of Species

Ruffed Grouse


It is the opinion of many hunters that ruffed grouse provide the finest table fare of any upland game bird. Yet, they are not widely hunted in North Dakota because their range is isolated.

Ruffed grouse do have a small but loyal following, though, and each year the Pembina Hills, Turtle Mountains and the sandhills in McHenry County yield a respectable harvest.

Ruffed grouse sport different color phases, specifically the color of the band on the tail feathers. The color of the band, whether it's red or gray, is not a reliable indicator of age or sex.

The central two feathers in a ruffed grouse tail, however, do reveal sex, but you have to pull them out to get started.

Photo of a ruffed grouse tail
The best way to determine the sex of a ruffed grouse is to pull out a central tail feather (marked by arrow) and measure it.

If you pull the central tail feathers from two ruffed grouse, and one is about an inch longer than the other, you know you have a male and a female, because males have longer tail feathers than females. If you have only one ruffed grouse, or you have two and the tail feathers are the same length, you need to measure the feather to determine sex.

Generally, the central tail feather of a male ruffed grouse is six inches or longer. Central tail feathers from a female are shorter than six inches.

The photo below shows a central tail feather from male and female ruffed grouse. The longer one measures about seven inches, and is from a male. The shorter one is less than six inches, and came from a female.

Photo of ruffed grouse feathers
If the central tail feather measures six inches or longer, the bird is a male. If the feather is noticeably less than six inches, the bird is a female. In the photo above, the top feather measures about seven inches, and is from a male. The bottom feather measures about 5 ¾ inches, and is from a female.

The appearance of the band on the central tail feathers can also indicate sex, but this method is not always reliable. A distinct black band indicates a male, but males do not always have a complete band. The band on a female is generally not complete.

Ruffed grouse are the most difficult species to age, Kobriger said. The best way to tell juveniles from adults, Kobriger added, is to look at the outer wing primaries. If the outer primaries are growing, indicated by the bluish "quill," the bird is an adult. If the seventh or eighth primaries are growing, the bird is a juvenile.

In addition, if the outer two primaries are rounded and smooth, the bird is an adult. If those feathers are more pointed and frayed, the bird is a juvenile. The accompanying photo shows a good example of that difference.

Photo of ruffed grouse wing
This photo of two ruffed grouse wings shows a good example to use for determining age of ruffed grouse. The wing on the left is from a juvenile, characterized by frayed ends on the outer primary feathers. The wing on the right is from an adult, distinguished by smooth round edges on the outer primary feathers.

However, ruffed grouse live in a more protected environment than other upland game birds. They don't fly as much, and when they do fly, they don't fly as far. Since ruffed grouse don't use their wings as much as other upland game birds, their wing tips may not show much wear, making it more difficult to differentiate young and adult birds whose primary wing feathers are no longer growing.

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