The Impact of Lobster Fishing on Sea Urchins and Coral in Galapagos

In Galapagos the pencil sea urchin Eucidaris thouarsii is a “corallivore” that greatly influences the ecological structure of Galapagos subtidal marine communities. While E. thouarsii does not commonly feed on coral elsewhere, in Galapagos it tends to diversify its diet to include large amounts of coral. Overfishing of lobsters – predators of Galapagos sea urchins – allows E. thouarsii populations to boom, in turn causing the decimation of coral by sea urchin overgrazing. In order to protect the delicate Galapagos coral reef ecosystem, sea urchin populations must be controlled. Sustainable management of the Galapagos lobster fishery through strategies including the implementation of an ITQ system is the most effective method of sea urchin control. Introduction The Galapagos archipelago is uniquely located at the confluence of several major ocean currents including the Humboldt current, which carries Antarctic water north up the coast of South America, and the Cromwell current, which upwells cold deep water to the surface at the archipelago. Due to these cold water currents, the ocean surrounding the islands is Pencil urchins in rock crevices in Galapagos (courtesy of Nick Wenner).