GOSHEN – After years of sharp declines in their population, horseshoe crabs are making a modest return this year.
That is good news for Ruddy Turnstones, Sanderlings, Dunlins and other shorebirds who eat the crab’s eggs, according to Pat Sutton, program director for the Cape May Bird Observatory.
She led a field trip to Cook’s Beach here late in the afternoon, May 24.
While long time residents may recall seeing Delaware Bay waters teaming with horseshoe crabs rolling in with the tide in the past, on this day, only a few were seen. Many crabs may have been waiting for a high tide later in the evening.
Bird population counts show dramatic drops in the past 17 years. On May 24, 8,680 Red Knots were counted compared to 46,230 on the same date in 1989.
Sutton blames the over harvesting of horseshoe crabs which are used for eel and conch bait, ground up for fertilizer and their blood used for pharmaceutical testing.
“This is the first year that has looked hopeful,” she said, noting more crabs and eggs.
She said the shorebirds were not looking “starved,” this year.
In 2001, a no harvest zone was set up in the ocean from Atlantic City to Ocean City, Md., said Sutton, covering 1,500 square miles.
The state has placed a two-year moratorium on horseshoe crabbing, which would have opened in June.
Beach entrances from Villas, north to Maurice River Township on the bay, are roped off and feature signs asking residents to stay off the beach during the shorebird migration and crab mating season.
“It has made all the difference in the world,” said Sutton.
In 1989, 53,800 Ruddy Turnstones were counted. On the same date, this year, 12,175 were tallied.
Sanderlings, known for their habit of running back and forth with the breaking surf, have 80 percent of their population here in May.
Dunlin sightings dropped here from 81,000 in 1989 to 16,500 this year.
Sutton said 137,000 shore birds have been counted, breaking down to 62,000 on this side of the bay and 75,000 in Delaware.
Sutton said five species of birds fly non-stop from Southern, Central America to the Delaware Bay to feed on the crab’s tiny green eggs before departing to breeding grounds in the Arctic.
The Red Knot arrives here after flying 90 hours non-stop, using up every ounce of fat in their bodies, dependent on regaining their weight by feasting on crab eggs.
The eggs give the birds the strength to fly from here to breeding grounds in the Arctic tundra of Hudson Bay. The birds will eat as many as 9,000 eggs per day, explained Sutton.
Nearly the entire hemisphere’s population of Red Knots are along the coasts of Delaware Bay feeding on eggs this time of year, said Sutton.
Horseshoe crab expert John Heuges, told field trip participants the creatures are not really crabs but more closely related to spiders and scorpions. The creatures, which have been on this planet for 260 million years, have ten eyes and seven sets of legs, he said.
This time of year, favoring high tides during the full moon and new moon, the unique creatures climb onto the beach, mate, and lay eggs, which are buried in the sand. It takes the crabs 12 years to reaching breeding age.
Sutton said the crabs were over harvested in the late 1880’s and nearly disappeared until the late 1970’s when they returned in large numbers. Fisherman harvesting crabs in the 1990s again devastated the population.
Sutton said she could not find one crab in 1995 after over harvesting of the creatures. Fishermen dragged the bottom of the bay to catch the crabs in huge numbers, she said.
Horseshoe crabs have decreased 75 percent in the past 11 years, she added.
In 1996, 2 million crabs were harvested.
In the past, do-gooders may have thought they were helping save the horseshoe crab population by flipping over crabs, stuck on their backs on the beach, allowing them to walk back to the bay. Heuges advises it is now thought the best policy is to stay off the beach during their two week mating time.
He recalls a time when beaches were so covered by huge flocks of birds that from a distance appeared shimmering white sand, “as far as you could see.”
On this trip, birds were only seen on a small offshore island and two stretches of Cook’s Beach.
Staying off the beach keeps flocks of shorebirds from being frightened away by people, dogs, or ATVs, said Sutton.
Listen to this week’s Herald podcast at www.cmcherald.com for a segment recorded on Cook’s Beach.
Contact Fichter at (609) 886-8600 Ext 30 or at: jfichter@cmcherald.com
Stone Harbor – Bob Ross thank you for all your years of volunteer service to the community of Stone Harbor. A Lifelong resident And property owner. 10 years on school board, 6 years on zoning board they can't…
