Predator home range size mediates indirect interactions between prey species in an arctic vertebrate community

Indirect interactions are widespread among prey species that share a common predator, but the underlying mechanisms driving these interactions are often unclear, and our ability to predict their outcome is limited.
Changes in behavioural traits that impact predator space use could be a key proximal mechanism mediating indirect interactions, but there is little empirical evidence of the causes and consequences of such behavioural-numerical response in multi-species systems. 
Here, we investigate the complex ecological relationships between seven prey species sharing a common predator. We used a path analysis approach on a comprehensive 9-year dataset simultaneously tracking predator space use, prey densities, and prey mortality rate on key species of a simplified Arctic food-web. 
We show that high availability of a clumped and spatially predictable prey (goose eggs) leads to a two-fold reduction in predator (arctic fox) home range size, which increases local predator density and stron...