ASSESSMENT OF MOOSE WINTER HABITAT CONDITIONS IN WESTERN WYOMING

Abstract

ABSTRACT: Over the past two decades, wildlife managers in Wyoming have documented that moose (Alces alces shirasi) populations within the 8 herd units of western Wyoming are declining.  A recent study indicated that habitat conditions were the primary factors responsible for moose declines in at least one herd unit.  As the first component of a larger effort to systematically assess moose winter range habitat throughout Wyoming, we assessed habitat for the Jackson and Sublette moose herds in 2007-2009. Winter ranges were assessed with a landscape approach to cover the area quickly using: 1) habitat mapping, 2) photo-documentation of willow and aspen communities, 3) risk/ succession assessment of aspen stands, and 4) detailed vegetation monitoring using Live Dead Index transects.  Within the Jackson Moose Herd Unit focus area, a total of 105,574 acres were evaluated and delineated into 403 habitat patches with specific vegetative data collected on 52 representative transects.  A total of 48,617 acres were assessed and delineated into 301 habitat patches with detailed vegetation data collected on 54 representative transects for the Sublette Moose Herd Unit.  Treatment prioritizations were made based on vegetation data.  Our data indicate that willow and aspen habitats are being over used and/ or are in decline in our study areas.  The majority of the willow regeneration is not able to escape the browse zone as a result of current and historic browsing levels.  Many aspen habitats are successionally advanced to include conifers and aspen regeneration is not successfully growing through the browse zone.  These moose habitat inventories and assessments will be used as a template for implementing future moose habitat enhancements in Wyoming.  Management implications and the potential for wildlife and habitat managers to work cooperatively to ensure sustainable habitats are discussed.