Pots used to catch eels are killing scores of terrapins -- the Maryland state reptile and the beloved mascot of the University of Maryland -- according to a new study.

The report, published in the current issue of Estuaries research journal, estimates that each spring and summer about 190 terrapins in the Patuxent River area are trapped in eel pots and drown.

The report is the result of a two-year project by Thomas Radzio, an Ohio University graduate student, and his professor, Willem Roosenburg, who spent months planting scores of pots along the Patuxent River in Calvert County and pulling them up to record the results.

The tragedy of their findings, Roosenburg said, is that the drownings, which kill about 3 percent of the local terrapin population, could have been prevented by attaching a cheap device to the pots to block the turtles.

"It's an extensive problem that can be solved with a low-cost, simple technology," Roosenburg said.

The study has been forwarded to Maryland Department of Natural Resources officials, who said it is the first extensive study they have seen on the issue.

"I haven't heard much about this from the eelers I talk to," said Keith Whiteford, a DNR biologist. "But then, I don't know how eager they would be to disclose if eel pots are killing a bunch of terrapins."

The study used three types of pots and deployed them throughout the Patuxent River. One set of pots had small entrance funnels, common in new pots. A second set had large funnels, which are the more common type in use because the funnels widen over time. For the third type, the team outfitted a set of large funnel pots with a device made of PVC pipe designed to allow eels to enter but to exclude the turtles.

"It's something that takes less than a nickel to create and retrofit onto the pots," Roosenburg said.

During two months of fishing in August and September 2002, the large pots captured 55 terrapins along with the eels, with a catch rate of 0.5 terrapins per 24-hour set of pot fishing. The pots outfitted with a turtle excluder caught the same amount of eels but no terrapins.

A longtime industry in Southern Maryland, eel fishing hauls in an average of 380,000 pounds of eel in Maryland every year, according to DNR statistics. During the peak spring season, commercial eelers can use more than 10,000 pots in a month throughout the Chesapeake Bay and tributaries. The eels caught are used mostly for bait in the United States or are shipped to Europe and Asia, where they are a popular food.

The eel pot study is similar to research Roosenburg conducted in the 1990s on terrapin deaths by crab pots, which led to a new regulation requiring turtle excluders on crab pots.

"The problem is just as extensive if not more extensive than what we found with crab pots," Roosenburg said.

Roosenburg, who has studied terrapins for two decades, is known in some parts of Maryland's coast as the "turtleman."

He said his work on the environmental conservation of terrapins is just a byproduct of his main research into the turtles' sexual behavior and gender determination.

Still, he said, he hoped the recent study and another one he and Radzio plan to publish in coming months will lead to new regulations protecting terrapins.