Can crabs kill like a keystone predator? A field-test of the effects of crab predation on mussel mortality on a northeast Pacific rocky shore.

摘要: Predation can strongly influence community structure and ecosystem function, so the loss of key predators have dramatic ecological consequences, unless other predatory species in system are capable playing similar roles. In light recent outbreak sea star wasting disease (SSWD) subsequent depletion west coast populations, including those keystone predator Pisaster ochraceus, we examined whether large mobile crabs could play a role as on mussels (Mytilus californianus) rocky shore Northern California. Using combination removal exclusion cages found that mussel mortality was 43-294 times greater uncaged treatments versus caged treatments. Mortality at low tidal elevations due to predation by (Cancer productus Romaleon antennarium); confirmed presence shell fragments documented attacks wax snail replicas. Laboratory feeding assays indicated crabs, per unit biomass basis, consume almost twenty-five many day than stars, which together with results our field experiment, suggest an important maintaining function through their shores where P. ochraceus rare, absent, or been depleted SSWD.