A four-part plan including special fishing regulations, experimental walleye stocking, cormorant control and lake habitat improvements moves ahead on Leech Lake, the DNR reports.
Special walleye regulations this year include a protective slot of 18 to 26 inches, four-fish bag limit and one over 26 inches possession limit.
"The prevailing message that started to spread was that Leech Lake was dead," said Henry Drewes, DNR regional fisheries manager. "That's unfortunate because the lake has the third strongest level of walleye brood stock we've ever measured. Those fish have the potential to produce strong future year classes if they're protected and the conditions are right. What's important for anglers is those fish are still out there in the lake to be caught. In our angler surveys, we're actually hearing walleye fishing on Leech has been better than expected, even though anglers aren't able to keep a lot of fish."
The experimental regulations will be monitored over the next five years with annual walleye sampling and angler surveys in 2005 and 2010.
In early May, 7.5 million marked walleye fry were stocked in an effort to better understand the lake's natural walleye production. This information is important, Drewes said, because the target population goal for the lake's double-crested cormorant colony will be at least partially based on that information.
The lake's colony of cormorants, which can consume up to a pound of fish per day per bird, ballooned to nearly 10,000 birds last summer. The colony is being blamed for the absence of younger age classes of walleye in Leech Lake in recent years.
A culling operation on Little Pelican Island reduced nesting pairs to about 600. It was suspended in late June to protect the other colonial water birds on the island. The sharpshooters will continue to take about 20 birds per week by pass shooting throughout the summer for a diet study, however. That study, which will be conducted by graduate students from the University of Minnesota, will help determine a sustainable population level for cormorants on Leech Lake.
The lake's level of natural walleye reproduction will be measured by estimating the ratio of marked to unmarked fish collected this summer in trawling and seining samples, according to Harlan Fierstine, Walker area fisheries supervisor for the DNR.
"Beginning in early July and throughout the summer," Fierstine said, "we'll collect young-of-the-year walleyes to determine what the ratio of natural versus stocked walleye is in the lake. This information will help determine the optimal level of brood stock and provide insight into the level of natural reproduction that is occurring on Leech Lake."
The final part of the Leech Lake action plan is habitat protection. According to Drewes, a primary focus will be controlling invasive species, Eurasian watermilfoil, curly leaf pondweed and the Chinese mystery snail, which appeared in the lake in the summer of 2004.
Eurasian watermilfoil was found in five harbors in the summer of 2004. Efforts to control the invasive species late last summer were largely successful. The DNR is offering resort owners and guests personal training on how to identify the aquatic plant and clean boats to prevent its further spread. The DNR is also planning additional treatment for the harbors where the plant was found this summer. A survey was conducted earlier this year looking for curly leaf pondweed, but none was discovered.
"I'm really encouraged by what I'm seeing and hearing on Leech Lake," Drewes said. "Angler success for larger walleye has been good and we are approaching the peak season for bass and muskie fishing."
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