American eels, such as these, were caught in the Allegheny River at Springdale.

Call it the summer of the oddball species.

There have been reports of enough exotic fish -- from tilapia to shrimp -- on Western Pennsylvania rivers in recent weeks for a Steel City stir fry.

Now add to the list the 40-inch American eel that Joe Koricich landed with his 7-year old nephew, Bobby Carr, off the banks of the Allegheny River in Springdale.

"I started fishing in the river over 50 years ago when bullhead catfish and carp were the only things you'd catch," said Koricich of Penn Hills. "These days I never know what it's going to be. I caught my first mooneye last year. It was the shiniest fish I've ever seen ... it almost looked like a fishing lure."

Although eels are indigenous in the Delaware River, they have been reported occasionally in the Ohio River drainage, of which the Allegheny is a part. Koricich's eel is the third this year, according to Lee Murray of Lock Three Bait and Tackle, a popular spot with area anglers. "Eels have been in the river ever since I can remember, but they're very uncommon," Lee said.

"We don't hear about it often," said Mike Kaufmann, a Pennsylvania Fish and Boat Commission fisheries biologist who works in the southeast corner of the state. "They would have come all the way from the Gulf of Mexico. Think of the locks and dams they'd have to go through, and all the tributaries they could have peeled off into along the way. I've seen 40-inch eels in tributaries that you and I could straddle."

For an eel to range as far as Lock No. 3 on the Allegheny is a tribute to both the eels' survival instinct and improving water quality.

"They're more pollution tolerant than some species," Kaufmann said, "but cleaner habitat and water make it easier for them to stake out new turf. If they find habitat that's better than anything they're used to, if they find better food and fewer predators, they'll put on body fat and improve the quality of their eggs. That's what Darwin meant by survival of the fittest. He wasn't talking about physical fitness. He was talking about reproduction."

Kaufmann said eels are so determined, they'll slither up a trickle of water or over wet grass, and even go up and around dams, if need be, to get to the place they will inhabit for life. But no matter where that is, every American eel -- and every European eel, on the other side of the Atlantic -- starts its life in the Sargasso Sea in the infamous Bermuda Triangle. And they return there just once in a lifetime to spawn. The spawning migration occurs August through October. Eels die after reproducing.

"I'd say [Koricich's] eel is as big and old as an eel gets, and has probably spent 15 or 20 years in the Allegheny River," said Kaufmann, who dismissed the possibility that it was planted. "Highly unlikely. Most people wouldn't know how to get one and since they seek cover and hide most of the time, viewing them in an aquarium would be difficult."

He said eels are a mystery even to some fisheries biologists: "They're fascinating, but they're a species about which we don't know a whole lot."

Although eels were commercially harvested for their meat by the tens of thousands in Pennsylvania a century ago -- traces of weirs, or traps, still exist on the Susquehanna and Delaware rivers -- that industry is gone. Not so on the rest of the East Coast, where eels have been exploited to the point the U.S. Fish and Wildlife Service is considering eels for threatened or endangered status, which would reduce Pennsylvania's liberal creel limits -- 50 a day, year-round -- to zero.

"What threw up the alarms was the St. Lawrence drainage basin, one of the largest producers of eels, where numbers have just plummeted," Kaufmann said.

"When the markets collapsed in Asia, it became desirable for fishermen to move up and down the East Coast harvesting young eels, and then shipping them to Asia to be cultured. They'd get $400 a pound for these fish, but it put enormous pressure on the species."

Eels leave the Sargasso Sea as flat willow-leaf shaped larvae that can easily glide on ocean currents, and gradually morph into more elongated, translucent fish as they move toward fresh water, Kaufmann said. They start to pigment once they hit rivers and streams, about a year after hatching, and become what are known as yellow eels. Males find brackish water, where they remain all of their lives. Females venture further.

"That eel in the Allegheny was undoubtedly a female, because a male would never have traveled that far into fresh water," Kaufmann said. "Their determination is pretty amazing. It's how their numbers spread. It gives them a survival advantage."

When eels assume a silver color they have sexually matured, and are then ready for their one and only journey back to the place of their birth.

Eels will eat crayfish, small fish, and even dead fish, hiding behind rocks or below undercut banks and burrowing into the river's substrate in order to ambush prey, Kaufmann said. "They're opportunistic. If they got a shot at a frog or a salamander, they wouldn't pass that up either."

Koricich caught his eel on a shiner in about 10 feet of water. Although it was deep-hooked -- a common problem with eel fishing -- he said he released it.

"They're hard to grasp and they flop around a lot," Kaufmann said. "They're strong -- the son of a guns can fight -- and you've got that slimy coating to deal with. It's easier if you keep your hands wet.

"Sometimes we'll find jelly donuts in our survey nets. It's what an eel leaves behind before he manages to slip through the net."

Although eels appear to be smooth, they have tiny scales and fins. They use their tails as a wedge to go underneath rocks. "They'll actually pull themselves backwards with their tails," Kaufmann said.

"They'll also sort of curl and twist around your arm when you're trying to release them, but not to put a hold on you. They're just trying to get free."