Slithering From Science's Grasp

Eels' Bay Decline Spurs Study, but Answers Elusive

On the banks of the Potomac River yesterday, three scientists went fishing for eels, baiting tube-shaped traps with clams to catch the slithery creatures.

"Bingo," Maryland state biologist Jim Thompson said as he pulled a trap out of the shallows. Four eels were wriggling around inside.

In the scope of the Chesapeake Bay watershed -- where an army of scientists is always monitoring the water, counting the fish, even measuring the algae -- this was a minuscule effort.

But in the world of eels -- a native species that has long been the Chesapeake Bay's forgotten fish -- it was something big.

The eel is routinely harvested by watermen who sell some of their catch overseas for Asian and European diners and keep the rest for bait. But it was never as important to watermen as rockfish, blue crabs or oysters, and was shunned by recreational anglers. So scientists never spent much time learning about eels.

In recent years, though, as the eel population has declined, scientists have begun to study the fish -- and to realize how confounding the creatures can be.

"It's one of those deals where the more we know, the more we don't know," said Marcel M. Montane of the Virginia Institute of Marine Science.

The American eel is not as fearsome as it's more famous cousins: It is not electric, and doesn't have rows of sharp teeth. It eats small animals and fish, can grow to be several feet long and can live more than 20 years.

Even so, the eel has one of the most mysterious life cycles of any creature in the bay: Adult eels end their lives by swimming out to the Sargasso Sea -- a part of the Atlantic Ocean near Bermuda -- to spawn and die, researchers said.

"It's amazing that we've known [the eel's] life cycle since the early 1900s," when watermen were catching eels during their migrations to and from the bay, said David Secor, a professor at the University of Maryland Center for Environmental Science. "But the key details continue to elude us."

Researchers also are trying to understand the decline in the eel population in the past decade. The commercial take of eels in the bay fell from 992,739 pounds in 1993 to 597,509 pounds in 1999.

Scientists suspect an illegal trade in "glass eels," as young, transparent eels are called. Officers with Maryland's Department of Natural Resources have tried to stop watermen who were catching and selling the eels to be raised in captivity in Japan.

Another possible explanation is the general rise in popularity of sushi, which spread the popularity of eel, called unagi in Japanese. And scientists are studying the bay pollution's effect on the species.