Leucocytozoon bonasae in Ruffed Grouse; Its Possible Relationship to Fluctuations in Numbers of Grouse

During the summer of 1949, Canada geese were observed by pilots, survey crews, and the author on the Colville River, from the headwaters to the 70th parallel on the arctic slope of Alaska. Reports by Eskimos that the geese nest on cliffs of the river was confirmed by locating a single nest and seeing a number of paired birds on the steep north banks. The banks are almost vertical and capped with overhanging tundra. The base continually sloughs into the river during periods of intense flow. The slopes are barren except for scattered bunches of grass and an occasional patch of willow. Climbing the 50to 300-foot slopes is treacherous. A search of about 10 miles of bank resulted in finding only one nest but geese were flushed from many inaccessible points. The nest (July 9, 1949) was in the open, 45 feet above the turbulent water and 50 feet below a rock ledge. The incubating goose was not flushed but the mate was nearby and left the scene. Geese were seen and flushed from similar locations along the Colville. The cliffs of the Colville are undoubtedly a favorite nesting site of the Canada goose in the Arctic. Non-breeding birds were observed on the river bars. Weights and measurements of five nonbreeders, banded on July 12 and 13, identify the species as Branta canadensis leucopareia. A survey party located a nest with 6 eggs on the Etivluk River on July 5, 1949. Accepted for publication January 9, 1953.