Mountain Lions Spark a Trophic Cascade at a Small California Preserve
Stanford researchers report that increasing visits by mountain lions to Jasper Ridge Biological Preserve trigger a trophic cascade: deer browsing declines and woody plants, especially oaks, rebound—reaching about a 64-fold increase in density. The effect also reshapes smaller predators’ behavior (coyotes and bobcats become less nocturnal; fox activity rises), with rabbit activity dropping. The mechanism is behavioral (ecology of fear) rather than direct predation, and the team cautions that weather and other factors could contribute to the observed plant increase; the recovery is partial, not complete. The study highlights that even small, peri-urban reserves connected to larger wilderness can exhibit significant ecological dynamics.