Right around the time of the full moons in May and June, horseshoe crabs have been on their most frenzied behavior for millions of years, and this year will be no exception.
Head down to bay beaches just before high tide on the full moon over the next couple months, treading lightly, and you will be treated to one of nature’s oldest courtship rituals — the spawning of scores of horseshoe crabs, an ancient species that has changed little since its ancestors were swimming around the earth’s seas more than 400 million years ago.
The New York Horseshoe Crab Monitoring Network collects data on the number, size and gender of horseshoe crabs that come up on the beach at 16 sites throughout Long Island early each summer.
They rely on citizen volunteers of all ages to help them tag and measure the horseshoe crabs.
Long used as bait for conch and eel fishing, horseshoe crabs populations have been on the decline due to the use of their blood in biomedical testing.
A threatened shorebird known as the red knot, which feeds on horseshoe crab eggs, has also been impacted by the decline in horseshoe crab populations.
New York has voluntarily reduced its quota for harvestable horseshoe crabs below the level set by the Atlantic States Marine Fisheries Commission, and catching horseshoe crabs is prohibited at several sites on Long Island, including Cedar Beach in Mount Sinai and the Fire Island National Seashore, where they crawl ashore in massive numbers.
Cornell Cooperative Extension’s Marine Program is working with the New York State Department of Environmental Conservation to coordinate and implement the New York Horseshoe Crab Monitoring Network, in which volunteers take to the beaches just before high tides around the evenings of full and new moons in May and June to count and masure horseshoe crabs.
The sites include Pike’s Beach in Westhampton Dunes, East Landing Road on Squires Pond in Hampton Bays, South Harbor Road in Southold and Cedar Beach in Mount Sinai.
The Monitoring Network also provides an iPhone and Android app for volunteers to use to help input data.
Volunteers will meet at several East End locations over the next month, at all hours of the evening to account for high tides at individual locations.
For example, the June 1 meeting at Squires Pond in Hampton Bays will be at 2:10 a.m., while the June 26 meeting will be held at 11:52 p.m. and the June 29 meeting will be held at 1:06 a.m.
At South Harbor Road in Southold, volunteers will meet at 1:59 a.m. on June 1, 11:27 p.m. on June 26 and 12:52 a.m. on June 29.
Volunteers will meet at the bay side of Pike’s Beach in Westhampton Dunes on May 31 at 11:45 p.m., and on June 26 at 9:31 p.m. and June 28 at 10:46 p.m.
For more information on getting involved with the monitoring network, visit nyhorseshoecrab.org.