BISHOPVILLE -- Julie Weeder and Al Wesche are slopping around in a waist-high brackish soup of algae, water grasses and lily pads, collecting inch-long, spaghetti-thin creatures that look like tiny snakes.
Pulling a simple, handmade wooden and screen trap from the water near the dam that hinders the flow of Bishopville Pond into the St. Martin River in rural Worcester County, the pair of marine biologists pour their slithering catch of baby American eels into a plastic bucket.
After Wesche samples the water's temperature, salinity and oxygen level, the elvers are counted and released to continue a 2,000-mile journey that has taken them from the depths of the Sargasso Sea between Bermuda and Puerto Rico to the shallow, brownish-green waters of the state's coastal rivers and streams.
Along the Atlantic coast, the elvers arrive the same time every year, destined to continue a life cycle that even the biologists say sounds a little like science fiction.
In the pond, a few elvers -- those not being gobbled by an opportunistic blackbird -- struggle to crawl up a dripping mass of underwater grasses that clings to the side of the dam.
"They're so small, almost anything -- fish, turtles, birds, muskrats -- can be a predator," says Weeder, who is leading a three-year Department of Natural Resources survey of elvers in Maryland waters. "What's really amazing is that this very thing is happening in virtually every freshwater stream, creek and river along the whole East Coast. Just imagine how many there are out there."
Scientists say there are huge gaps in what they know about these fish (they have gills but can also breathe directly through their slimy, mucus-coated skins) that populate East Coast waters, including the Chesapeake Bay and its tributaries, in untold numbers.
Spawned among the rich seaweed of the Sargasso Sea, the eels begin life as clumps of larvae that float northward on the warm currents of the Gulf Stream, growing into transparent elvers during the year it takes them to reach the mid-Atlantic region. Some drift into the bay, eventually making their way up rivers and streams as far north as Pennsylvania.
Others make their way into the coastal bays near Ocean City or other coastal waterways, seeking freshwater habitats where they will spend most of their lives.
If not caught by watermen who sell their catch (for about $1.50 a pound lately) to wholesalers who ship live adult eels to markets in Europe, a female can grow to a yard long and weigh nearly 20 pounds before reaching sexual maturity at about age 15. The much smaller males usually reproduce after four years.
For both sexes, procreation begins each fall with a return to their tropical spawning grounds where they mate and die. Each pair produces millions of fertilized eggs.
Or at least that's how the experts think it all happens. No one has ever witnessed the spawning ritual, and scientists have no idea why the animals return or how they find their way.
'Glass elvers'
Adding an aura of mystery, says DNR field researcher Wesche, is the springtime arrival of the "glass elvers," so called because they don't take on coloration until after they have fed in fresh water.
Thousands of the transparent babies enter inland waters at night, but only during the dark and full phases of the moon.
"It's the darndest thing I've ever seen. Everything happens exactly by the book, with the moon just right, usually on a rainy night," says Wesche, who has spent the last 25 years with DNR working on the Eastern Shore. "Nothing's supposed to go exactly like the book."
Researchers have estimates on the number of adult eels caught and sold in the United States each year, but they have no idea how many billions of elvers arrive each spring.
Reported harvests of adult eels -- which are packed in ice and shipped alive to Europe -- have ranged from 423 tons to 1,813 tons between 1970 and 1995, but catches averaged 700 tons between 1983 and 1995. The smallest harvest, 423 tons, came in 1994.
The problem, according to the Atlantic States Marine Fisheries Commission, a 15-state consortium, is that reporting methods vary widely from state to state, an issue that will be addressed when the nation's first Atlantic eel-management plan is adopted.
"There's just nothing hard and fast to look at," said Vic Vecchio, a marine resources specialist for New York's Department of Environmental Conservation who has served on a committee of the fisheries commission.
Scientists suspect that overfishing of the tiny elvers might pose a threat to the species, but no one's sure.
"For a long time, there simply was not a lot of attention paid to eels in this country," says Tina Berger, a spokeswoman for the fisheries commission. "Eels have begun to grow in importance in the last few years."
Popular in Asia
As eel harvests began dropping in Asia, buyers in Japan, Taiwan and China began offering as much as $350 a pound for elvers, which are shipped to aqua-farms where they are fed special diets and grown to market size in about two years.
Four states -- Maine, Connecticut, South Carolina and Florida -- allow fishing for elvers, but the lure of easy money has caught marine fisheries officials unprepared.
In states with a legal season for elvers, ever-larger numbers of fishermen scramble for position to scoop up slimy nets full of elvers that can soon be converted into cash. In Maryland and other states where elver fishing is not allowed, poachers find the risk of being fined and losing their equipment well worth taking.
Maryland Natural Resources Police arrested three elver fishermen at Bishopville Pond a couple of years ago, and Officer John Myszka says likely streams and creeks are watched regularly.
"It's really a hit-or-miss thing in terms of staking out these places," Myszka says. "But when you've got this kind of money involved, somebody is going to be trying it. I've heard that the price doubles at about every step in the chain. That's a lot of money all the way up the line."
Maryland officials think they are ahead of the game, having started the elver count before the fisheries management plan requires a similar effort from other states.
Ultimately, says the DNR's Weeder, who also tends elver traps along the Patuxent River in Prince George's County and the Sassafras River in Kent County, increased study will tell scientists whether the species needs protection.
"We can't say that they're endangered by any means, but we are concerned about the cumulative effect because they are fished at every point in their life cycle before they reproduce," Weeder says. "In Maryland we do have some data from a study done in the early '80s, but that is really the only point of comparison we have."