Horseshoe Crab Harvest Ban Must Expand to Other States

Conservation groups are making a fresh push to expand a moratorium on harvesting horseshoe crabs in the Delaware Bay. New Jersey adopted a moratorium in 2008 because the declining crab pollution endangered migratory shore birds that feed on crab eggs. Other bay states – Delaware, Virginia and Maryland – have reduced quotas and banned the harvesting of egg-laying female crabs. However they have stopped short of a full ban.

“Horseshoe crabs are an important part of the Delaware Bay ecosystem. Their eggs are vital to the survival of migratory shore birds that feed on them. Without the horseshoe crab the red knot and other birds would disappear. We’ve done our part in New Jersey with a moratorium on harvesting horseshoe crabs since 2008. Now we need to go after other states in the bay, Delaware, Virginia and Maryland, and get them to fully ban the horseshoe crab harvest. If they don’t, endangered species of migratory birds like the red knot may become extinct,” said Jeff Tittel, director of the New Jersey Sierra Club.

Horseshoe crabs are typically harvested to be used as bait. Biomedical companies also harvest the crabs for their blood. Lysate, an extract from horseshoe crab blood, is used to test for toxins in products. The new campaign by conservation groups aims to ban crab harvesting aims to fully restore the horseshoe crab population in the bay by 2030. The current population is only at an estimated 30 percent of the bay’s capacity.

“Horseshoe crabs are harvested and cut as bait for eels, catfish, and conch. The cost of bait produced from these harvests is about $100,000 a year. By contrast, a 2006 study found that tourism based on observing migratory shore birds brings $34 million a year into Cape May County each year. Horseshoe crabs are also harvested by biomedical companies which use their blood in products. Those companies should be using synthetic alternatives instead,” said Tittel.

The overharvesting of horseshoe crabs has threatened the existence of migratory shore birds, especially the red knot. The number of red knots dropped to below 15,000 in the early 2000s. The red knot numbers have bounced back to about 30,000 since the New Jersey moratorium began. However that is only about a third of the amount during the 1980s, before crab overharvesting began.

“The red knot population was plummeting by almost 10% a year before the moratorium, from 100,000 down as low as 15,000. The population has rebounded somewhat, with latest figures around 30,000. That isn’t enough to withstand shocks such as severe weather in Arctic breeding grounds or overdevelopment along migratory routes,” said Tittel. “The moratorium has stabilized the crab population but the numbers are still far too low to support the red knot and other shore birds. Experts say egg densities need to be at least 50,000 per square meter to boost migratory bird population. That figure was just 7,000 in 2017.”

Other species threatened by the decline in horseshoe crabs include the semipalmated sandpipers and ruddy turnstones. Restoring the crab population will also benefit fish and other marine species that feed on the crabs. Those species have also been depleted by the decline in crabs.

“We cannot allow an ecosystem to be destroyed and migratory birds to go extinct. Other states must join us and place a moratorium on all horseshoe crab harvesting. The Sierra Club has recognized the Delaware Bayshore as one of the nation’s most important treasures that are currently in peril — a list that also includes the Arctic National Wildlife Refuge and other unique ecosystems. We worked to get this moratorium and we intend to keep taking action to save this region and the endangered species that inhabit it,” said Jeff Tittel, director of the New Jersey Sierra Club. “We need every state along the bay to ban the crab harvest until there is a significant and sustained increase in the population. Otherwise endangered species like the red knot will become extinct.”