Moose (Alces alces) Population Survey in Yukon-Charley Rivers National Preserve, November 2025
Cash JS, Sorum MS, Cameron MD. 2026. Moose (Alces alces) Population Survey in Yukon-Charley Rivers National Preserve, November 2025. Science Report. NPS/SR—2026/417. National Park Service. Fort Collins, Colorado. https://doi.org/10.36967/2317273
We conducted aerial surveys for moose (Alces alces) in Yukon-Charley Rivers National Preserve (YUCH) in November 2025. These surveys were conducted using GeoSpatial Population Estimator (GSPE) protocols that were adopted in 2003 and is the 8th such survey conducted in the Preserve. Survey units are approximately 5.6 mi2 and are surveyed by a pilot/observer pair in a tandem fixed-wing aircraft. We surveyed 102 units covering 568 mi2, representing 18% of the 3,096 mi2 survey area, at an average pace of 6.4 minutes/mi2. We observed 216 total moose, comprised of 113 cows, 32 calves, and 71 bulls. The GSPE population estimate was 729 moose (90% CI: 587–872), resulting in an estimated density of 0.24 moose/mi2, which was similar to the long term 2003–2022 average of 0.27 moose/mi2. The 90% confidence interval for the total moose estimate (±19% of the mean) met our goal of 20% or better of the mean relative precision. Estimated sex ratios were 34 calves:100 cows, 6 yearling bulls:100 cows, and 57 bulls:100 cows. We recommend a continued conservative management of harvest to ensure that population stability continues and is able to absorb natural stochastic environmental fluctuations despite a baseline low density.
- Type
- Published Report
- Authors
- Cash, James; Sorum, Matthew; Cameron, Matthew
- Date of Issue
- 2026-03
- Publisher
- National Park Service
- DOI
- 10.36967/2317273
- Units
- NRSS , YUCH