We compared sea otter recovery in California (CA) and British Columbia (BC) to determine how key ecosystem properties shape top-down effects in seagrass communities. Potential ecosystem drivers of sea otter foraging in CA and BC seagrass beds that we examined include the role of coastline complexity and environmental stress on sea otter effects. In BC, we found greater species richness across seagrass trophic assemblages. Furthermore, Cancer spp. crabs, an important link in the seagrass trophic cascade observed in CA, was less common. Additionally, the more recent reintroduction of sea otters, more complex coastline, and reduced environmental stress in BC seagrass habitats supported the hypothesis that sea otter foraging pressure is currently reduced in more northern latitudes. In order to manage the ecosystem features that lead to regional differences in top predator effects in seagrass communities, we review our findings, their spatial and temporal constraints, and present a social-ecological framework for future re- search
