LITTLE ROCK —This summer’s extreme heat is taking a toll on fish in Arkansas, the state Game and Fish Commission says.

The commission said hot water was a factor in the deaths about 3,000 fish that were found in the Petit Jean River near the Logan-Yell county line in western Arkansas on Friday.

“There was just a large number of fish in a small area. Just too much oxygen demand by too many fish combined with the hot water” to cause the deaths, said Bob Limbird, a district fisheries biologist with the Game and Fish Commission.

The fish killed included gizzard shad, sunfish, freshwater drum, minnows and crappie.

The commission also said it has been monitoring conditions at trout fisheries across the state because trout are cold-water fish and therefore especially vulnerable to rises in temperature.

“We’ve had some fish die-offs,” said agency spokesman Keith Stephens. “On the Little Red (River) we had some trout that were dying, but we’ve got some water moving through there and I think that helped that area.”

The commission said about 50 trout died near Pangburn in northern Arkansas late last month when the temperature of the Little Red River rose above 70 degrees. The Game and Fish Commission announced Wednesday that because of the dangerously warm water, trout normally stocked in the area would be stocked a few miles upstream until temperatures improve.

The agency also worked with U.S. Sen. Mark Pryor, D-Ark., and U.S. Rep. Rick Crawford, R-Jonesboro, to persuade the Southwestern Power Administration last week to increase the flow of water through the Greers Ferry Dam into the Little Red River to bring temperatures down. The dam releases water that is cooler than the river water because it comes from the bottom of Greers Ferry Lake.

“Ideally, you don’t want anything probably above 65 degrees” for trout, said Billy Lindsey, owner of Lindsey’s Resort in Heber Springs, which caters to trout fishermen. “They can do all right with a little bit warmer than that, but when it starts breaking into the 70s then you’re certainly going to run the risk of losing some fish — which up to now has been very minimal.”

Lindsey’s Resort is about two miles downstream from the dam and about 18 miles upstream from the spot where Game and Fish Commission biologists found the 50 dead trout, which was not considered a major fish kill.

Lindsey said the river temperature at the resort was in the high 40s or low 50s on Friday, and the temperature near Pangburn was about 65, thanks to the increased water flow through the dam.

“I think it’s making a huge difference,” he said.

The Southwestern Power Administration agreed Tuesday to increase the minimum flow by 40 percent for one week and to monitor the results daily. At the end of the week it will determine whether the flow needs to be increased further.

Lindsey said the top two concerns at trout fisheries are the possible deaths of fish from the heat and the possibility of stocking restrictions, neither of which has happened far enough up the Little Red River to affect his resort.

The state has an economic interest in protecting trout because trout fishing accounts for about 6 percent of the state’s tourism revenue, he said.

“We’re probably talking about a $200 million-a-year business,” he said.