Researchers at an aquarium in Connecticut want to study how the egg-laying habits of horseshoe crabs may be changing.
Two recent studies from the Maritime Aquarium in Norwalk found a 2% to 9% decline in horseshoe crab populations in the Sound each year since the 1980s.
“We analyzed six regional data sets spanning up to the last 46 years, and from looking at those data sets, we could see that the populations were declining,” said Rebha Raviraj, a project manager in the aquarium’s conservation department.
Scientists say their decline will have a ripple effect throughout the environment.
"They serve as a vital link in the food web for multiple endangered species, including fish, turtles and thousands of migratory shorebirds," Raviraj said.
Raviraj said globally this 400 million year old species is facing a variety of threats including over-harvesting, habitat loss and climate change, but she said more information is needed to narrow down the source of the key problems in the Sound.
To help answer those questions, the Maritime Aquarium has begun a new study looking at horseshoe crab egg production on the Sound's beaches.
"That will be a great way to actually quantify egg presence on different Connecticut beaches and get an understanding of how the juvenile populations are doing and then target specific threats and specific factors that could be affecting their populations," Raviraj said.
The study is being privately funded by one of the aquarium's donors.
The Maritime Aquarium and numerous other organizations would like to see the American horseshoe crab listed as an endangered species by the federal government.
Two years ago, Connecticut banned the harvest of horseshoe crabs, but New York’s Gov. Kathy Hochul vetoed similar legislation last year.
New York does have harvest bans during May and June, when the crabs come ashore in the Sound to breed, and it has harvest limits for commercial bait fishermen.
It takes at least nine years for a horseshoe crab to reach sexual maturity, so Raviraj said it is too early to tell if Connecticut’s harvest ban is having an impact.
