Moose Distribution and Abundance in Rocky Mountain National Park: 2025 Inventory Results
Deacy WW and Abouelezz HG . 2026. Moose Distribution and Abundance in Rocky Mountain National Park: 2025 Inventory Results. Science Report. NPS/SR—2026/428. National Park Service. Fort Collins, Colorado. https://doi.org/10.36967/2303644
We conducted a parkwide thermal infrared aerial survey in Rocky Mountain National Park (ROMO) in 2025 to inventory moose (Alces alces shirasi) distribution, estimate abundance, and characterize demographic composition to inform moose and wetlands management. The survey built on 2019–2020 pilot work and was designed to provide spatially comprehensive, defensible data for management and NEPA decision‑making. Survey results showed that moose were widespread across ROMO but were concentrated in riparian and wetland habitats. Density estimates were higher in areas classified as more suitable habitat than in less suitable areas and demographic indices indicated a population mostly consisting of cow moose. Comparison with earlier surveys indicated moose density increased 49% from 2020 to 2025. Parkwide, we estimated a density of 0.259 moose/km2 (HDI 0.207, 0.312) and a total population of 240 moose (HDI 190, 287). These findings suggest moose could have increasingly negative effects on willow and wetland health in ROMO, with potential to undermine ongoing restoration efforts. Because ROMO functions as a refuge from harvest and lacks the population regulation typically provided by large carnivores, the observed density and population data suggest timely management actions to curtail moose herbivory will be needed to restore wetland integrity.
- Type
- Published Report
- Authors
- Deacy, William; Abouelezz, Hanem
- Date of Issue
- 2026-04
- Publisher
- National Park Service
- DOI
- 10.36967/2303644
- Units
- NRSS , ROMO
- Keywords
- Abundance, Demographics, Distribution, Inventory, Moose, Riparian, ROMO, Thermal Infrared Aerial Survey, Wetlands