Fauna Series No. 4

Fauna of the National Parks — No. 4 Ecology of the Coyote in the Yellowstone

CHAPTER XI:
BIRDS IN RELATION TO COYOTES

RICHARDSON GROUSE

Remains of Richardson grouse (Dendragapus obscurus richardsoni) were found in five droppings; grouse, either Richardson or ruffed grouse, in five droppings. One of the grouse was a chick.

The blue grouse population seems to fluctuate very little in the Yellowstone region. This grouse is not abundant, but still is frequently found, especially on ridges and high slopes. It is commonly found at lower elevations in summer, but generally moves to higher elevations in winter. C. H. Merriam (Hayden, 1873), who made a trip in 1872 through Yellowstone and Jackson Hole, states: "The species was not abundant, being met with chiefly in the Teton Mountains."

During the middle of May 1937 a number of males assembled each evening on a sagebrush slope near Antelope Creek to strut and hoot. On May 18 I saw seven or eight males assembled and heard others close by. A fresh coyote dropping picked up on the area contained the foot of a blue grouse. There were four other fresh coyote droppings on the road nearby containing mainly elk hair. The assemblage of droppings made it appear that the coyotes had been attracted to prey on the grouse. On May 23 a ranger informed me that he and another ranger had found, in the fenced buffalo pasture below the place where the grouse were strutting, a blue grouse with the head eaten off and in another spot a mass of feathers. This seemed to indicate that the coyotes were getting several grouse. It occurred to me that these birds may have been found along the buffalo pasture fence after being killed by flying into it, so I walked along the entire fence. I found the body of the grouse mentioned above, but on searching found its head 7 feet on the other side of the fence. It had been severed when the grouse hit the fence. Another grouse had suffered a deep cut at the base of the skull where it had struck the wire. Remains of three blue grouse and four ruffed grouse were found along the fence, five of the kills being recent, and all had been eaten except two ruffed grouse. Obviously all of these were carrion, resulting from the presence of the wire fence. Two of the blue grouse remains were about 200 yards directly below the spot where the grouse had assembled each evening and where I had found grouse remains in a coyote dropping. Since these blue grouse in the buffalo pasture had been eaten recently, there was some probability that they were the source of the grouse remains in the dropping found in the road. Nevertheless, it still seemed that the drumming grouse must have attracted the coyotes to the spot, because of the number of fresh droppings there. However, the true explanation of the frequenting of the area by coyotes came to me as I climbed the slope to the strutting area. Upon examining a spot about 75 yards below the grouse rendezvous, from which a raven was flushed, I found several neck vertebrae of an elk and some bloody elk hair. Apparently an elk carcass rather than the blue grouse had been the attraction. The incident is here related to show how easy it is to draw incorrect conclusions from field observations.

On June 10 near Trumpeter Lake some blue grouse feathers were found on a dirt mound at the entrance of a burrow. Upon examining the vicinity, the main mass of feathers was found 5 yards from a spot below some telephone wires. This grouse probably had met death by flying into them.

On November 6, 1937, I located remains of a blue grouse which had recently flown into the buffalo pasture fence and on May 27, 1938, remains of another were found along the fence. It is likely that grouse, because of their precipitous rapid flight, are killed more frequently by flying into wires and other objects than are other birds.

No evidence was secured to indicate that coyotes were preying extensively on this species.

Figure 54— A blue grouse in early spring. There are occasional records of grouse, killed by hitting wires,
forming carrion for coyotes.
Teton National Forest, April 1936.

RUFFED GROUSE

Ruffed grouse (Bonasa umbellus umbelloides) were identified in two droppings. In addition, the contents of any of five droppings which were identified as "grouse," may have belonged to this species. It is my impression that the ruffed grouse is slightly more plentiful in Yellowstone than is the blue grouse. The population seems to remain rather stable, and marked cycles of abundance and scarcity apparently do not occur regularly. C. H. Merriam (1873) in 1872 found that the ruffed grouse "was not an abundant species though it was found throughout the pine forests from Teton Canyon to the Yellowstone." This agrees with my observations during the past 10 years in which I have been familiar with the Yellowstone-Jackson Hole area. Coyote depredations on ruffed grouse do not appear to be serious.

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Last Modified: Thurs, Dec 20 2001 10:00:00 pm PDT
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