Ecosystem features determine seagrass community response to sea otter foraging

Margot Hessing-Lewis; Erin U. Rechsteiner; Brent B. Hughes; M. Tim Tinker; Zachary L. Monteith; Angeleen M. Olson; Matthew Morgan Henderson; Jane C. Watson

doi:10.1016/j.marpolbul.2017.09.047

USGS · 70194644

Ecosystem features determine seagrass community response to sea otter foraging

Margot Hessing-Lewis·Erin U. Rechsteiner·Brent B. Hughes·M. Tim Tinker·Zachary L. Monteith·Angeleen M. Olson·Matthew Morgan Henderson·Jane C. Watson

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Abstract

Comparing sea otter recovery in California (CA) and British Columbia (BC) reveals key ecosystem properties that shape top-down effects in seagrass communities. We review potential ecosystem drivers of sea otter foraging in CA and BC seagrass beds, including the role of coastline complexity and environmental stress on sea otter effects. In BC, we find greater species richness across seagrass trophic assemblages. Furthermore, Cancer spp. crabs, an important link in the seagrass trophic cascade observed in CA, are less common. Additionally, the more recent reintroduction of sea otters, more complex coastline, and reduced environmental stress in BC seagrass habitats supports the hypotheses that sea otter foraging pressure is currently reduced there. 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 research.

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Marine Pollution Bulletin Article

Source-reported bounding extent: 33° to 53° latitude; -130° to -119° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Margot Hessing-Lewis, Erin U. Rechsteiner, Brent B. Hughes, M. Tim Tinker, Zachary L. Monteith, Angeleen M. Olson, Matthew Morgan Henderson, Jane C. Watson. 2017. Ecosystem features determine seagrass community response to sea otter foraging. https://doi.org/10.1016/j.marpolbul.2017.09.047

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