Making Peace with a Pest

Which critter, man or horseshoe crab, is the real problem?

by Bruce Schimmel

The full moon threw an orange glow across the Delaware Bay, as the creatures emerged. Propelled by the tide, thousands of horseshoes crawl out to spawn on the beach, each dragging a jagged stinger.

Not to worry. Horseshoe crabs look scary, though they're actually rather gentle. I can pick up a horseshoe and tickle its gills � and expect nothing more than a gentle salute from a set of soft claws.

And the horseshoe's stinger, called a telson, has no poison and can't sting. Though, ironically, that rigid tail poses more of a danger to the critter itself.

Tumbled in the surf, some crabs flip over and essentially stake themselves in the sand. Though relatively few suffer this fate, what a mess those few can make. Stranded animals rot in the sun, creating a stench that attracts flies and disgusts humans.

Until recently, homeowners here on Prime Hook Beach � 20 miles north of Rehoboth � used to hire front-end loaders to bury the rotting crabs by the ton. Now these homeowners welcome their annual spawning.

Prime Hook Beach has just joined with other nearby communities in declaring their beach a horseshoe crab sanctuary � meaning no one may harvest or hurt them.

Glenn Gauvry, whom everyone calls the "Horseshoe Crab Guy," engineered this pact between man and former pest. A friend of mine, Gauvry convinced people that it was better to go with the flow than to battle these ancient mariners.

For decades, beach homeowners would snap off the crab's telson and toss the carcasses into the bay � only to have them wash up again and rot on the shore.

So Gauvry came up with a solution, exquisite in its simplicity. Instead of killing the creatures, he suggested returning them to the bay alive.

Sure, Gauvry's scheme was an "unnatural" human intervention. But something had to be done to save the horseshoe. Because between the carnage on the shore and the harvesting of crabs for bait, the horseshoe crab population was declining quickly.

Having one of the world's oldest creatures edge toward extinction not only endangered marine life, but was also hurting migrating shorebirds � which feed on the horseshoe's excess (and unviable) eggs to finish their flights.

Gauvry's simple motto turned the tide for the horseshoes. "Just flip 'em," he said. Just unstick the critter from the sand, turn it right side up, and let it crawl back into the bay.

Over the past several years, Gauvry met with dozens of state officials, hundreds of homeowners and thousands of schoolchildren. And now his mantra has become the official gospel � as the status of horseshoes has climbed from pest to prize. (For more, go to www.horseshoecrab.org.)

This simple idea is working. As we walk the beach tonight, Gauvry is thrilled with this year's spawn. The surf line is solid with creatures tumbling like drunken BattleBots. Males wait along the shore to hitch a ride inland on the females. Gauvry says we could walk out 100 feet into the Delaware entirely on the backs of horny boy crabs.

There's lots of spawning, and yet the beaches around us are clean � except for lines of extra eggs that birds will snap up for their flight.

The Delaware Bay, about 70 miles downriver from Philadelphia, contains most of the world's horseshoes. Last year, it held some 19 million, the highest in a decade. This year, says Gauvry, seems even more promising.

Horseshoes have been spawning longer than any other marine animal, and their role in the Earth's ecology has evolved over some 350 million years. By contrast, humans have been around for about 100,000 years.

So which critter, man or crab, is the real pest? The jury is still out, but the odds are sort of absurd. On one side is a bay teeming with creatures who've got time and tide on their side. On the other, human beings, who've built their houses on sand.

Our recent sea change toward the horseshoe crab may be a bit like inviting the inevitable. Because at some point, even an infant species like us will realize that we don't have enough power, or maybe even the right, to keep some creatures from retaking their legacy.

(bruce@schimmel.com)