Summer Notes on the Sooty Grouse of Mount Rainier

THE AUK:

A QUARTERLY JOURNAL OF

ORNITHOLOGY.

VOL. XL¾I. JULY, 1929. NO. 3.

SUMMER NOTES ON THE SOOTY GROUSE OF MOUNT RAINIER.

BY R. A. JOHNSON.

Plates XII-XIII.

DURING the summer of 1926, between the dates of June 15, and September20, frequent observationswere made on the habits of the Sooty Grouse(Dendragapus f. fuli#i•osw Ridgw.) of Mount Rainier, Washington. The summer range of this species is restrictedto the alpinemeadow zone, a habitat extendingaround the mountain approximately between the elevations of five thousand and six thousand five hundred feet. The ground cover of this habitat consistslargely of heather meadows,small mountain ash, and mountain willow thickets interspersedwith clumps and individual trees of alpine fir (Abies la•ocarpa) and mountain hemlock (T•u#a merte•ia•a), the branchesof which usuallydroop so that the lowestones touch the ground. The 1926 seasonwas two or more weeks early for the wild flowers, the snow having disappearedin Paradise Valley by June 15. Such an unusually early seasonmay have affected the breedingseason of the birds although I considerit doubtful. During the latter part of June I saw severalindividual female Sooty Grousearound Paradise Valley and ParadiseCamp. These birds moved about leisurely, quietly feeding, and seemingly unafraid of man. If pursued,they usually made their get-away on foot and were only induced to flight by a close chaseand even this flight terminated in the branchesof a nearby tree. 291 Ta• Amr, Vo•. XLVI. PlaTE Xll.

UPPER.--MALE SOOTY GROUSE•PERFORMING. LOWER.--SAME BIRD ONE MINUTE EARLIER. 292 JoHnson,The Sooty Grouse ofMount Rainier. JulyAuk

The male Sooty Grouse, commonlycalled "hooter" because of the character of his call, is seldomseen with the female after the egg laying season,except in instanceswhere a secondbrood is raised. Often the "hoot" of the male is mistaken for that of an Owl. It is made after the bird has assumeda half strutting attitude with the air sac on each side of the neck inflated, so that he resemblessomewhat a cooing Pigeon. During an extended observationof oneof thesemales I noticedthat eachperformance consistedof five distinct hoots, the first and the last of which were of two syllables,and the three interveningones of one syllable, thus: "Ooh-whoo, whoo, whoo, whoo, ooh-whoo." The bird is perfectlywilling to be disturbed. It will fly to the branchof a nearbytree, or walk a few yardsto one sideand then, oftenquite unconcernedin the presenceeven of a considerableaudience, inflate the largeair sacsof the neck and utter this guttural hoot, which, becauseof its peculiar quality soundsfar distant even thoughit may be uttered only a few yards away. With regard to the broodsof the Sooty Grouse! may mention the followingrecords from my notebooks. On June 28, a broodof chicksjust out of the nest was sighted. On August 4, a female and five chicks one third grown were found feedingnear Sluskin Falls; elevation 6000 feet. In these chicksthe main tail feathersof theadult plumage were beginning to show. On August11, a femaleand three half grownchicks were seen at an elevation of 5300 feet. The chickswere feedingon insects. Their adult tail featherswere half way out. On the samedate, a female with three small chicks,estimated to be ten days old, and evidentlya secondbrood, was found feedingon insectsat an elevation of 5300 feet. On September3, a female with seven young about three- fourthsgrown was seenat an elevationof 5000 feet. The young resembledyoung Turkeys with adult tail plumagecomplete, and leathered tracts on the necks. On September6, / observeda broodof Sooty Grousegoing to roost. ! locatedthem by their low cacklingnoise which is often heard at such times. This cackle is a subdued one and is somewhat similarto that of the domesticfowl, exceptfor the absenceof THE AUK, VOL. XLVI. PLATE XIII.

FEMALE SOOTY GROUSE IN Ta•.. the outburstingnotes with which the domestichen ends her performance. In going to roost each bird settled upon a thick mat of branchesabout eight feet from the trunk of the tree and from twelve to thirty feet from the ground. In this positiontheir dusky colorblended somewhat with the mossand lichen-covered branches. The birds settle singly,usually with the head turned toward the tip of the broadfrond-like branch upon which they perch,yet concealedfor the most part by overhangingbranches. With regardto local distribution,several broods were success- fully reared in ParadiseValley and the outskirtsof the large ParadiseCamp grounds,but I saw the Sooty Grouseseldom in other parts of its natural range. I believe that there was an unusual concentration of birds within a narrowzone around the campground, and that probably the birdswere there enjoying the measureof protectionfrom their natural enemieswhich they found in the shadowof this human habitation. Certainly these birds were not attracted by food for not oncedid I see them cometo secureany food distributed by man. On September8, eight inchesof snowfell in the habitat zone of the Sooty Grouse. This remainedand increasedto ten inches on September17. When the snow fell the broodswere still together,but as the snowdeepened they immediatelyexhibited a certainconfusion by aimlesslywandering about. By September 20, broodshad lost their identity and the birdswere found for the mostpart singlyor in pairs,perched among the higherbranches in the clumpsof alpinefir and hemlock. The Manlius School, Manlius, N.Y.