Distribution, activity and range use of male caribou in early summer in Northern Yukon, Canada

Wendy Nixon,Donald E. Russell,Arthur M. Martell

doi:10.7557/2.6.2.644

Abstract

Males of the Porcupine Caribou Herd separated from females from the onset of spring migration until they joined them on the calving grounds in late June or early July, 4-6 weeks later. From late May to late June males spent an average of 50% of their time feeding and less than 2% standing and trotting/running. Males spent an average of 29% of their time lying and 19% walking, except in mid-June (40% lying, 6% walking). The average lengths of active and resting periods were 112 minutes and 104 minutes, respectively, from late May to mid-June, but decreased sharply in late June to 78 minutes and 69 minutes, respectively. Tussock meadows were selected in late May and early June, wet sedge meadows were avoided until late June, dwarf shrub heaths were avoided after late May, and alluvial willow thickets were avoided in late May and early June but were selected in mid-June and late June. Caribou fed primarily on lichens and Vaccinium in late May, lichens and Eriophorum in early June, Eriophorum in mid-June and Salix in late June.

Highlights

The Porcupine Caribou Herd {Rangifer tarandus grand) calves on the Arctic Coastal Plain of northeastern Alaska and northwestern Yukon, and winters primarily in north-central Yukon and adjacent Alaska
Male caribou follow the females on spring migration along essentially the same routes leading from the two principal wintering areas, the Ogilvie Mountains of north-central Yukon and the Arctic Village region of northeastern Alaska
In early June, at the time of calving, males are distributed in a broad crescent south and east of the calving grounds (Fig. 2b)

Summary

Introduction

The Porcupine Caribou Herd {Rangifer tarandus grand) calves on the Arctic Coastal Plain of northeastern Alaska and northwestern Yukon, and winters primarily in north-central Yukon and adjacent Alaska. For a variable period before and after calving, males are segregated from females. It has been suggested that this segregation occurs because males follow the northward initiation of growth of forage while pregnant females move quickly to the calving grounds for other reasons, such as predator avoidance (Whitten and Cameron, 1979). Recent proposals for a seaport, quarries and roads in northern Yukon in the area used intensively by males in early summer have focused attention on the need for information on that component of the herd. Study area Investigations were conducted in northern

Methods

Results

Conclusion