Decline in horseshoe crabs concerns Bayshore council

Staff Writer

This year has seen a sharp decrease in horseshoe crabs monitored at five area beaches, according to Joseph Reynolds of the Bayshore Regional Watershed Council.

“We found out that the horseshoe crab population is declining, and primarily female crabs are declining,” said Reynolds, who is the co-chair of the council.

According to a report by the council, only 828 horseshoe crabs were monitored in 2015, the lowest in the group’s seven years of monitoring. Over the past seven years, the group had averaged 1,788 crabs a year.

“A lot of it has to do with the weather, we really got slammed hard with it this year, but also a big part of it is they’re taking a lot of crabs out. New York State still has horseshoe crab harvesting going on … and it’s impacting our monitoring efforts here in Raritan Bay and Sandy Hook Bay,” said Reynolds, who estimates that New York took out over 200,000 crabs this year.

According to data recorded by the council, for every female crab the council monitored, there were about 20 males. According to Reynolds, female crabs are sought after in New York as bait due to the fact they tend to be bigger than males and their eggs can also serve as bait for eels.

The council, along with volunteers, monitors the horseshoe crabs at five area beaches.

Those beaches are Plum Island at Sandy Hook Gateway National Recreation Area, Many Mind Creek in the Borough of Atlantic Highlands, Leonardo Beach in Middletown Township, Conaskonk Point in the Borough of Union Beach and Cliffwood Beach in Aberdeen Township.

The council and its volunteers count and tag the crabs twice in May and twice in June. The dates correspond with the full and new moon, which is the height of spawning for the crabs.

Horseshoe crabs are vital to the shore’s ecosystem, and the news that there are fewer females could prove harmful.

“Horseshoe crabs are important because they provide food. Their eggs are very fatty and nutritious, so they provide food for migratory shore birds that come all the way from South America. [They] stop here to feed on those fatty eggs and get enough energy to continue up to the Arctic and start the next generation of shorebirds,” he said.

“If we lose those horseshoe crab eggs, we not only lose the horseshoe crabs but we lose shorebirds, which have been doing the same thing for thousands and thousands of years,” he continued.

The blood of the horseshoe crab is also prized in medical research to test vaccines.

“Anything that gets into your body has to get tested for contamination. That used to get tested on rabbits that would die in the process. Now it’s tested on horseshoe crab blood,” said Reynolds, who added that the crabs get their blood drained and most survive the process.

Reynolds believes education can help reverse the trend.

“We need to educate people about horseshoe crabs, on both sides of the bay, because a lot of people don’t know how important these crabs are,” he said.

For Reynolds, there is a danger that the crabs could go extinct.

“Here’s a species that has been around 350 to 400 million years and they’re in danger of being lost,” he said, noting that horseshoe crabs are already in danger in the Pacific due to overdevelopment.

Contact Michael Nunes at