History of Horseshoe Crab Harvest on Delaware Bay

Abstract

Horseshoe crab (Limulus polyphemus) harvest on Delaware Bay is not a new event. Early settlers to the New World reported use of horseshoe crabs by Native Americans for food, tools, and to enrich soils for growing crops. Literature from the mid- to late 1800s documents the use of horseshoe crabs for fertilizer and to supplement livestock feed. By the 1870s and for almost a century thereafter, well over a million crabs were harvested annually from Delaware Bay, in support of a regionally significant “cancerine” (fertilizer) industry. Subsequent to the cessation of the cancerine industry in the mid-twentieth century, relatively low-scale use of horseshoe crabs as bait for American eel and other fisheries existed. This use exploded in the 1990s, as eel markets expanded and use of horseshoe crabs for bait in a rapidly emerging whelk (Busycon spp.) pot fishery intensified along the East Coast of the United States. With horseshoe crabs spawning in mass along the shores of Delaware Bay, and little or no regulations in place, harvest pressure once again approached levels of the fertilizer use days. Simultaneously, an ongoing need for bleeding of horseshoe crabs to provide Limulus amebocyte lysate (LAL) for biomedical use, and growing recognition of the importance of horseshoe crab eggs on Delaware Bay as a key stopover food source for migratory shorebirds prompted concerns about observed declines in the population, resulting in implementation of significant management measures to ensure the sustainability of the species.