Posted on 03/20/2004 4:58:13 PM PST by nuconvert
Researchers Try to Unravel Mystery of Disappearing Eels
Mar 20, 2004
Virginia Smith/ The Associated Press
ST. AUGUSTINE, Fla. (AP) - At 3:30 a.m., Kim Tugend sweeps a dip net across the face of the Guana River dam. From the concrete ledge in the dam house, it is a steep drop to the water, and Tugend's net is long and unwieldy. Her only light comes from her tiny headlamp. From the ledge, in the dark, she can see tiny jellyfish flashing an otherworldly purple light, and the churning waters are deafening. When she pulls her net up and empties it into a pan, there's a wriggling gelatinous mass. It's jellyfish and larval fish - none bigger than a fingernail, all clear but for the black spots of their eyes. She dumps the pan back over the ledge.
Tugend, a researcher with the Florida Fish and Wildlife Conservation Commission, is looking for baby eels, which get stuck in dams. She hasn't found any in days, not here - in a state park north of St. Augustine - nor at the Rodman Dam near Palatka. At 4, 4:30 and 5, her dips pull up everything, it seems, but eels.
"This is so awful," she laughs, scrawling another zero onto her dip log. "I'm gonna get depressed. I'm gonna get a complex."
The eels, arguably, have it much worse. They are rapidly, mysteriously disappearing, which is why Tugend is surveying them.
No one has ever seen an American eel hatching or spawning, but both happen somewhere beneath the Sargasso Sea, a rotating oval of relatively calm water spanning thousands of miles in the Atlantic.
The eels begin life there as flat, leaf-shaped larvae, which ride Gulf Stream currents toward the rivers of the eastern seaboard. As they approach freshwater their bodies grow compact and snakelike, though still clear and only a few inches long.
Some of the "glass eels," as they are called, enter the St. Johns River and migrate to inland lakes, where they grow fatter and darker and spend most of their lives. Others ride the currents higher, hopping off the Gulf Stream as far north as Nova Scotia, already pigmented and the size of worms. Eels shun light on their journey, forcing researchers like Tugend to work at night.
In the mid-1920s a Dutch scientist made multiple missions to the Sargasso Sea to learn where eels spawn, but he never quite found the spot. Though commercial eel fisheries existed then in the northern states and Canada, little was known about the eels themselves. Only a few years before had science determined that the leaf-like larvae, thought to be a species of saltwater fish, were actually young eels.
Back then Billy Ruth's father and grandfather fished the St. Johns River. All the eels they caught they dumped in the woods, leaving foul-smelling piles for pigs and raccoons. Billy Ruth did too until, around 1960, two men came from Philadelphia offering him a nickel a pound for them.
Ruth remembers eating a smoked eel once, "when I was drunk," and hated it. Early European settlers ate a lot of eel, but more recently, even where eel was fished in quantity, Americans considered it mainly a baitfish. Europeans, though, considered it food - and as stocks of the European eel began to dry up, demand rose for the nearly identical American species.
Trucks with tanks carried the eels north, where they were sent live on planes to Europe. By the 1980s, prices were much higher, and Ruth once caught 19,000 pounds in six weeks.
Earlier this month Ruth waited in the morning mist on the porch of his Pierson fish store. The eel truck was on its way, and his six-week haul of eels - 852 pounds - swam in a holding tank outside. All of them were a drab dark green, the color of eels not sexually mature.
Ruth chewed Southern Pride tobacco, and two fellow fishermen waited with him.
"Used to be that (catch) would take a week at the most," said Ruth. "I've been eeling about 40 years, and ... the most I ever got was $3.50 a pound for them. But there were some eels then. There ain't now."
Today, he would get only $2 a pound.
In the 1980s Billy Ruth used to have to watch his traps for poachers, but he doesn't anymore. Only a handful of eelers are still active on the St. Johns.
All the eels caught south of Philadelphia go on the same truck - and that truck delivers them to a single exporter. In the '80s, competing exporters kept prices high. Now that there's only one, prices are artificially low.
Billy Ruth thinks eels have been overfished and are ripe for a comeback. Kim Tugend also thinks they're overfished, and pointed out that eels are taken at every stage of their life cycle.
Researchers also see other potential reasons for decline: dam turbines chewing up too many eels on their way out to sea; parasites and toxins; too much seaweed being harvested in the Sargasso, somehow affecting spawning; diminished habitat.
The Atlantic States Marine Fisheries Commission began investigating the decline in 1999, bringing on scientists in every state where eels occur. Tugend's data will be part of this survey.
Nationwide, catches are down at least 80 percent since 1970, commission reports say. A full stock assessment for eels will not be ready until next year, but Lydia Munger, the eel study's coordinator, called the preliminary findings "pretty grim."
If overfishing and dams prove the culprits, eels might stand a chance. Eels have always been ubiquitous, researchers say, and tough - they're often spotted climbing up the sheer faces of dams. Fishing can be halted or limited until the eels replenish, and eel ladders can help them over dams.
But scientists worry there's a force more ominous at work. They are following the latest oceanographic findings carefully.
European eels, which spawn in the Sargasso like their American cousins but ride the Gulf Stream all the way to Europe, are in even worse shape than American eels, with catches down almost 99 percent since the 1960s.
The Gulf Stream brings warm water from the tropics to the North Atlantic. As that current moves north it gives heat and moisture to the atmosphere, making European countries warmer than they otherwise would be for their latitude. The process leaves behind colder, saltier water that sinks far below the surface and flows back south in a worldwide "conveyor system" of currents.
Researchers at Woods Hole Oceanographic Institution in Massachusetts are monitoring whether salinity changes in polar regions - the result of melting ice caps and precipitation - are causing the Gulf Stream to slow down or change course.
If larval eels can't hop off it at the right time and place, or before their stored energy runs out, they might simply be dying at sea.
A slowing of the Gulf Stream would be bad news for humans, too.
"If too much freshwater enters the North Atlantic, the conveyor could cease," wrote Woods Hole researchers on a Web site titled "Abrupt Climate Change: Should we be Worried?"
"Heat-bearing Gulf Stream waters would no longer flow into the North Atlantic, and European and North American winters would become more severe," the oceanographers wrote.
The eels, if any remain, would have long seen it coming.
(steely)
Are you still with us, shaggy?
It´s such an easy question,
Why can´t I get an answer?~ E. Presley, March 18, 1962
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