The Seasonal Distribution of a Migratory Mule Deer Herd

Abstract

Rocky Mountain mule deer (Odocoileus hemionus) were trapped, marked, and released on the Silver Lake winter range in south-central Oregon, and their subsequent movements were observed from June, 1960, through October, 1963, to determine ranging habits. A total of 752 deer were marked on four areas of the winter range, and an estimated 497 were later observed on the summer range. The summer range of marked animals encircled the winter range, except that no animals summered in areas northeast of the winter range because of lack of suitable habitat. The largest percentage of animals summered in areas south, southwest, and west, and within 30 miles of the winter range. Deer from any one of the four trapping areas did not move to a particular part of the summer range but were found throughout the area. The average size of the summer range for individual mule deer of the Silver Lake herd was approximately 1 square mile. Individual movement on the winter range was determined by retrapping. The mean movement of animals on the winter range was less than one-fourth mile from the point of original capture. Individual deer returned to the same area of the winter range each year. A movement and seasonal distribution study was undertaken by the Oregon State Game Commission in 1959 as part of an ecological study of Rocky Mountain mule deer. The study was designed to determined (1) the summer range of deer utilizing the Silver Lake winter range, (2) the extent of the area used by individual animals on summer and winter ranges, and (3) whether deer from four different areas of the winter range used separate parts of the summer range. To accomplish these objectives, deer were livetrapped and marked on the Silver Lake winter range, and information on their subsequent movements was obtained from all possible sources. The study area, located in south-central Oregon, is bounded on the west by the crest of the Cascade Mountains and on the east by the central Oregon high desert. Elevations range from 4,500 to 5,500 feet above sea level with some peaks rising to 8,000 feet. Summer range vegetation is characterized by ponderosa pine (Pinus ponderosa) in association with various understory species such as bitterbrush (Purshia tridentata), snowbrush (Ceanothus velutinus), and manzanita (Arctostaphylos parryana var. pinetorum). Sagebrush (Artemesia tri1 A cooperative project of the Division of Wildlife Research, Oregon State Game Commission, and the Department of Fisheries and Wildlife, Oregon State University, partially financed with Federal Aid to Wildlife Restoration Funds under P.-R. Project W-53-R. 2 Present address: U. S. Forest Service, Umpqua National Forest, Roseburg, Oregon. 345 BUECHNER, H. K., A. M. HARTmOORN, AND J. A. LOCK. 1960. Recent advances in field immobilization of large mammals with drugs. Trans. N. Am. Wildl. and Nat. Resources Conf. 25:415--422. COWAN, I. McT., A. J. WOOD, AND H. C. NORDAN. 1962. Studies in the tranquilization and immobilization of deer (Odocoileus). Canadian J. Comp. Med. and Vet. Sci. 26(3):57-61. FLOOK, D. R., J. R. ROBERTSON, O. R. HERMANRUDE, AND H. K. BUECHNER. 1962. Succinylcholine chloride for immobilization of North American elk. J. Wildl. Mgmt. 26(3): 334-336. PISTEY, W. R., AND J. F. WRIGHT. 1961. The immobilization of captive wild animals with succinylcholine. II. Canadian J. Comp. Med. and Vet. Sci. 25(3):59-68. TALBOT, L. M., AND H. F. LAMPREY. 1961. Immobilization of free-ranging East African ungulates with succinylcholine chloride. J. Wildl. Mgmt. 25(3):303-310. Received for publication May 1, 1964. This content downloaded from 157.55.39.177 on Fri, 18 Nov 2016 04:13:15 UTC All use subject to http://about.jstor.org/terms 346 Journal of Wildlife Management, Vol. 29, No. 2, April 1965