Wolf Predation Likely Eliminated a Beaver Colony in a Drought-Stressed Pond

Wolves and beavers increasingly co-occur across the Northern Hemisphere, yet direct observations of their interactions remain rare, and little is known about how beavers respond behaviourally to predation risk under natural conditions. On 29 December 2024, a wolf killed an adult beaver on a foraging trail in Białowieża Forest, Poland, among the first video-documented wolf-beaver predation events in Europe. Over the 53-day monitoring period prior to the predation event, wolves visited the trail on 4 days, while beavers were active on 33 of those days (62%), averaging 4.9 detections per day (7.9 on days with activity). This contrasts with experimental work showing that predator cues alone are often enough to sharply suppress beaver activity. The predation occurred during hydrological drought. The watercourse above and below the pond was nearly dry, likely leaving the colony with nowhere safer to go. We interpret this apparent risk tolerance as consistent with the risk allocation hypothesis, where prey with no low-risk foraging options cannot sustain antipredator behaviour without compromising essential foraging. Following the predation, the pond remained abandoned for at least 18 months. This expands on a previous report of ponds becoming inactive following wolves predating on dispersing beavers, suggesting predation can also displace established colonies, with potentially cascading consequences for water retention, nutrient cycling and vegetation dynamics. In drought-affected landscapes, wolf predation could plausibly act as a spatial filter, disproportionately removing these ecosystem engineers from suboptimal habitats. This is a hypothesis that warrants future testing. As droughts intensify under climate change, this could compound into a feedback loop. Fewer active beaver sites would mean less landscape-scale water retention, deepening drought and further constraining the beaver habitat that remains, and undermining the ecosystem functions that make beaver recolonisation so ecologically valuable.