CARBONDALE, Ill. -- Veteran angler Don Sanders remembers when there were so many largemouth bass at Crab Orchard Lake, annual tournaments reported record catches -- and few worried that the supply would run out.
"The population just started depleting overnight," Sanders said Tuesday. "We said, 'Something is happening here."'
What exactly is causing Crab Orchard's adult largemouth bass population to shrink isn't clear, Illinois Department of Natural Resources fisheries biologist Chris Bickers said Tuesday.
But new length and catch limits are needed to help replenish the popular fish, he said.
Starting April 1, Crab Orchard's largemouth bass must be 16 inches to be taken home, up from 15 inches currently, and catch limits will be cut in half to three fish per person from six, Bickers said.
The new restrictions are planned only for the 7,000-acre Crab Orchard, the state's fourth-largest inland lake and a popular spot for bass fishing. The number of largemouth bass, the most popular fish in the state's $3.5 billion fishing industry, has declined since 1998 at Crab Orchard, Bickers said.
That year, IDNR officials collected 98 largemouth an hour when they measured the fish at Crab Orchard, a number that dwindled to 34 an hour last year, Bickers said.
"It isn't clear why," he said.
Largemouth bass virus detected in Illinois last year might be one reason, he said. A three-year study has begun to give researchers answers.
And Crab Orchard's heavy fishing crowds -- it's home to tournaments through the summer -- probably adds pressure to the largemouth supply, Bickers said.