Two Gyrfalcon nestlings on a cliff nest with a distant valley and mountains behind them

Neil Paprocki

Gyrfalcon Prey Likely to Respond Differently to Climate Change

North America

Arctic habitats are changing rapidly due to accelerated climate change, impacting ecosystems and trophic webs (also known as food webs), constituting the greatest conservation concern for the Arctic. Landscape changes, including shrub expansion, can cause species’ ranges to shift and disrupt predator-prey relationships. Understanding drivers of species’ distributions and abundances is therefore critical for predicting impacts on trophic webs.

Two photos. Left is a Gyrfalcon in flight. Right is two scientists looking through a scope at a distant hill.
Bryce Robinson (L) | Curtis Evans (R)


A new publication by Michaela Gustafson and our Gyrfalcon & Tundra Conservation Program recently detailed the most important landscape characteristics that drive abundance for three small Arctic herbivores: the Willow Ptarmigan, Rock Ptarmigan, and Arctic ground squirrel. All are critical prey for Arctic raptors, particularly the iconic Gyrfalcon. To map herbivore abundance within known Gyrfalcon territories, researchers completed nearly 1,000 surveys across the remote tundra and used sophisticated analysis techniques to identify drivers of prey abundance and how they affect Gyrfalcon occupancy. 

They found that the three herbivore species had different habitat–abundance relationships, indicating that  different responses and vulnerabilities to climate-driven shrub encroachment are likely. Willow Ptarmigan were more widespread within Gyrfalcon breeding territories, with Rock Ptarmigan and Arctic ground squirrels having a patchier distribution. Gyrfalcons were more likely to occupy territories with higher densities of Willow Ptarmigan and Arctic ground squirrels, suggesting these species’ habitats are important for breeding Gyrfalcons in Alaska . 

Three photos. Top left is a Willow Ptarmigan. Top right is a Rock Ptarmigan. Bottom is two people seen from afar standing in a vast Alaskan landscape.
Bryce Robinson (top L) | Kara Beer (top R) | Bill Saltzstein (bottom)


These findings add to our understanding of Arctic predator-prey relationships and the impacts of future climate and habitat change on higher levels of this Arctic trophic web. Scientific understanding is a prerequisite of effective conservation, and this publication is one step that The Peregrine Fund has taken toward conserving Gyrfalcons and the Arctic ecosystem. Read the full publication here.