Potential Threats to Horseshoe Crabs on Cape Cod, Massachusetts

Abstract

The Atlantic horseshoe crab, Limulus polyphemus, is an ancient species with ecologically and economically vital roles in estuarine ecosystems. Most notably, the biomedical industry relies on an amoebocyte lysate in their blood for detecting bacterial endotoxins. Noticeable declines in the horseshoe crab population around Cape Cod, Massachusetts recently spurred a collaborative state-wide research effort. The Massachusetts Division of Marine Fisheries identifies three primary impacts as potential threats to the horseshoe crab population: direct harvest, effects of bleeding, and habitat loss. This project discusses those potential threats while explaining the human and institutional ecology involved with the horseshoe crab population around Cape Cod. Furthermore, this project pursues the idea that spawning habitat may be threatened around Cape Cod by an increase of, or poorly located, shoreline stabilization and beach nourishment projects. These activities are quantified and addressed on a spatial scale using beach nourishment permit data, personal communication with state agencies, a review of the state permitting process, and comparisons with previous research. The results show that while there are few newly constructed shoreline stabilization structures along Cape Cod, more than forty beach nourishment projects took place over the past five years. And while processes are in place to ensure the protection of coastal habitats and their species, the environmental review system is often overlooked.