Researchers tried out a new method called "electrofishing" that stuns the fishes and causes them to rise out of the water "like zombies."
A boat equipped with a humming generator that feeds a weak electrical current into the water successfully caused a variety of fish to float to the surface of the water in Tennessee Valley Authority lakes, the Associated Press reported.
The researchers scooped the temporarily stunned fish up with a net and placed them in an aerated tank. The team measured the fish, checked them for parasites and other diseases, and released them back into the water as they started to come out of their stunned state.
"I've learned there's a lot of fish in here," Bernie Fuller, a seasoned fishing enthusiast who went along for the research trip, told the AP.
"They're pulling some 3- to 4-pounders regularly and all day we may catch three or four that size," Roger Morris, another fisherman, told the AP.
The fish are not believed to experiencing lasting symptoms from the fishing methods.
"Generally speaking they recover within a few seconds to a couple of minutes," John Justice, a fisheries biologist with TVA, told the AP.
Using this method to examine fish could help researchers gain insight into the state of the bodies of water and better-preserve their well-being.
"By looking at the overall health and condition of the fish we collect we can tell a lot about what's going on with the fishery," justice said.
Protection groups such as the People for the Ethical Treatment of Animals argue that the method still causes the fish to feel pain, but it could be a useful tool for biologists.
Out of the 200 bass and crappie that were collected during the trip, all were released back into the water alive once they were done being examined. Other scientific methods are fatal to the fish, such as putting chemicals called rotenone into a sealed-off part of the water.
"They look real healthy," Morris said.
