2024-2025 Greater Voyageurs Ecosystem Wolf Population Report

During April 2024–April 2025, we studied the wolf population in the Greater Voyageurs Ecosystem (GVE), Minnesota to understand wolf population dynamics and how changes in population dynamics are connected to or influence predation behavior, wolf pup survival, and changes in prey density. Although our primary objective was to estimate wolf population density, we also wanted to estimate key population parameters including pack size, pack composition, recruitment of wolf pups, and territory size.

Our primary tools to study the wolf population were GPS-collars and remote trail cameras. We used locations from GPS-collared wolves to estimate the size and distribution of wolf territories in the GVE. After delineating the territories of almost half the packs in the GVE, we then calculated how much neighboring wolf pack territories overlap one another and, on average, how many neighboring packs surround a single pack’s territory. Calculating these metrics are important for accurately estimating wolf population density.

To estimate pack size, pack composition, and the number of surviving pups in each pack, we deployed 378 trail cameras across the GVE from December 1, 2024 to April 10, 2025—we refer to this timeframe as our “winter survey period”— to record repeated video observations of wolf packs during winter. In particular, we sought to record repeated, independent observations of each pack during the monitoring period. We considered observations to be independent if they were on a different day than any other observations of that pack. Multiple independent observations of a pack with the same number of members provides highly-reliable and accurate pack size estimates (Gable et al. 2024). Additionally, high-quality, repeated observations allow us to determine pack composition (number of breeding individuals, subordinate adults, and pups in pack) and to identify most—and often all—the individual wolves in a pack based on physical characteristics.