Altus-Lugert Lake is the latest body of water in southwest Oklahoma where fish are dying as a result of golden alga blooms.
The fish kill started the week before Christmas and became worse last week with several thousand fish dying in the lake, said Larry Cofer, southwest fisheries chief of the Oklahoma Department of Wildlife Conservation.
Most of the dead fish are shad but there also have been some sport fish that have been killed.
Golden alga is an aquatic plant whose blooms produce a toxin that is deadly to fish. It typically blooms in the winter when other aquatic plants are suppressed by the cold weather.
“We think that is what gives golden alga a competitive advantage in the winter,” Cofer said.
Altus City Lake had a golden alga outbreak in 2004. Last winter, trout stocked in the stream below Altus-Lugert Lake died because of the toxin and state wildlife officials confirmed the presence of golden alga in the lake.
“We have been expecting this,” Cofer said of the fish kill on Altus-Lugert.
The trout kill caused state wildlife officials to move the winter trout fishery in southwest Oklahoma from Quartz Mountain to Medicine Park this year.
There is no treatment in the winter for the golden alga blooms, Cofer said. It’s unknown how long the fish kill will last on Altus-Lugert, he said.
“It may be over or it may get really bad,” Cofer said. “There is no way to predict it.”
Golden alga has been slowly moving northwest from Texas lakes in recent years.
State wildlife officials are asking boaters and anglers on Altus-Lugert to help reduce the chance of golden alga spreading to other lakes by making sure to thoroughly clean their boats, live wells and fishing gear.
The toxin from golden alga blooms is not a health risk to humans, wildlife or pets. Anglers may still fish at Altus-Lugert and eat fish caught from the lake, Cofer said.