SPOONER, Wis. -- Wisconsin wildlife officials said bass catch-and-release might be working too well.

The Department of Natural Resources said a mail survey of bass anglers found they kept only 550,000, or 6 percent, of the 10 million bass they caught in 2006. In contrast, state anglers kept about 2.2 million of 7 million walleye caught, or about 30 percent.

DNR fisheries biologist Larry Damman in Spooner said high minimum size limits coupled with catch-and-release has resulted in many lakes with overabundant, stunted bass populations in which few largemouths ever reach legal size.

Fisheries managers want anglers to harvest more bass in northern Wisconsin, especially in Polk and Washburn counties, to keep population numbers in balance and improve growth rates.