Mesopredator release and avifaunal extinctions in a fragmented system

This influential study coined the practical demonstration of mesopredator release, showing that the decline of a dominant predator can unleash smaller predators with cascading harm to prey. In fragmented coastal sage-scrub of southern California, Crooks and Soule found that where coyotes were scarce, smaller carnivores including domestic and feral cats increased, and these mesopredators drove higher predation on scrub-nesting birds, raising local extinction risk. The work linked apex-predator loss to biodiversity collapse through an intermediate-predator pathway and made the case that conserving top predators can protect songbirds. It remains a cornerstone reference for cat-related mesopredator dynamics and for understanding how trophic structure governs prey persistence in fragmented landscapes.