Will Red Knots fly into oblivion like Passenger Pigeons?

RELEASE: Feb. 15, 2008 – Volume XL, No. 7

Our generation could witness the loss of one of nature’s most unlikely and spectacular partnerships. The migratory shorebird known as the Red Knot may be headed for extinction because its millennia-old relationship with New Jersey’s horseshoe crabs has been short-circuited. The New Jersey Marine Fisheries Council has voted to re-open a commercial harvest of horseshoe crabs, ignoring the science that reveals the plight of the little Red Knot.

Each spring, Red Knots make an amazing 10,000-mile migration from southern Chile, at the tip of South America, to the Canadian arctic. Their final and crucial stopover is along New Jersey’s Delaware Bay, where the world’s largest concentration of horseshoe crabs obligingly lays millions of eggs in the sand just as the Red Knots arrive. Red Knots and other migratory shorebirds have come to rely almost exclusively on these nutrient-rich eggs for food. They pack on the weight they’ll need to fly the last leg of their incredible journey and lay eggs in their arctic nests, all before the ‘midnight sun’ snowmelt makes food available.

Red Knots are declining at an alarming rate. In just two years, 30 percent of the surviving Red Knot population has disappeared. January 2008 counts of Red Knots wintering in southern Chile found only 14,000 birds. Most of these birds are aging adults, and breeding success in the Arctic has been very poor in recent years. In the early 1990s, when horseshoe crabs were abundant, the Red Knot population was about 125,000.

The Red Knot decline coincides with the decimation of the horseshoe crabs along the Delaware Bay. Female horseshoe crabs had been laying enough eggs to guarantee the future of themselves plus at least four shorebird species. But as crabs were harvested for commercial bait to catch eels and conch, the beaches were virtually emptied of egg-laying crabs.

In the past, New Jersey placed a moratorium on harvesting horseshoe crabs. But by a 5 to 4 vote on Feb. 11, the Marine Fisheries Council rejected a N.J. Department of Environmental Protection (DEP) recommendation to continue the current moratorium, opening the door once again for a horseshoe crab harvest in New Jersey.

“The Council ignored the science,” stated Dr. Emile DeVito, Manager of Science & Stewardship for New Jersey Conservation Foundation (NJCF). "There is simply no scientific support for harvesting any horseshoe crabs at this time.

“There needs to be a huge excess of horseshoe eggs on New Jersey beaches,” Dr. DeVito explained. “As female horseshoe crabs burrow down to lay their eggs, they turn up eggs laid earlier by other females. Red Knots depend on these exposed eggs for survival during their migration. The number of eggs on the beach last year was the lowest ever – 2,000 eggs per square meter – rather than the 50,000 per square meter that are necessary and occurred historically in the 1980s and well into the early 1990s. Currently, there are enough eggs for the crabs to reproduce and the crab population may be starting to rebound, but there are not enough eggs for the Red Knots. Red Knots are on a path to extinction in three years. Every living crab is still vital to the shorebirds."

The immediate future doesn’t look rosy. It takes at least nine years for horseshoe crab females to mature, and extra females have yet to arrive to breed on New Jersey’s beaches, even after years of reduced harvests along the Atlantic coast.

The vote by the Marine Fisheries Council was reckless. Endangered species biologists and environmental advocates looking to stave off the extinction of the Red Knot are now looking for options to reinstate the moratorium before the May harvest. Let’s hope we can act in time, so that the Red Knots’ years aren’t numbered!

I hope you’ll contact me at info@njconservation.org, or visit NJCF’s website at www.njconservation.org, for more information about conserving New Jersey’s precious land and natural resources.

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