Wolves use diverse tactics to track partially migratory prey

Area of Science:

• Ecology
• Wildlife Biology
• Movement Ecology

Background:

• Predators often track migratory prey over long distances, a phenomenon known as migratory coupling.
• While Arctic wolves tracking caribou exemplify this, most wolves are considered territorial and non-migratory, especially during pup-rearing.
• Individual variation in prey movements is increasingly documented, yet predator responses remain less understood.

Purpose of the Study:

• To investigate wolf movement strategies in response to partially migratory prey.
• To quantify how wolf packs utilize space in relation to elk seasonal and summer ranges.
• To challenge the assumption of juvenile carnivores as fixed spatial anchors.

Main Methods:

• Utilized concurrent GPS tracking data from 19 gray wolves and 99 elk in the Greater Yellowstone Ecosystem (2019-2021).
• Quantified wolf movement strategies by analyzing overlaps between wolf pack seasonal ranges and wolf-elk summer ranges.
• Observed pup movements from den to rendezvous sites.

Main Results:

• Wolves displayed varied movement strategies: migration, commuting, and residency.
• Some wolf packs relocated pups to rendezvous sites along or within elk summer ranges.
• This demonstrates flexible predator responses to prey mobility.

Conclusions:

• Wolf movement strategies are dynamic and influenced by the plasticity of their migratory prey.
• Changes in ungulate mobility, driven by environmental factors, can significantly alter predator space use and ecosystem dynamics.
• The study reframes our understanding of wolf territoriality and juvenile dispersal in response to prey availability.