Bringing back walleye to Green Lake
SPICER -- An aggressive, walleye stocking program in Green Lake is producing results, and will continue for at least three years.
"I'm hopeful we will continue to see improvement in the walleye fishing,'' said fisheries supervisor Bruce Gilbertson of the Department of Natural Resource's Spicer office at a meeting Monday evening at the Dethlef's Senior Center, Spicer.
Gilbertson and Dave Coahran of the fisheries staff told an audience of 20 that the DNR is committed to maintaining an aggressive stocking program until the winter of 2010-11, at which time it will be reviewed. Stocking in the lake has been continuous since 2000, with heavy stocking in 2007 to make up for a shortfall of available fry in 2006.
The plan calls for continuing to stock just over 3,000 pounds of walleye fingerlings each autumn. The fingerlings will be larger to enhance their survivability. There will be between 15 to 30 fish per pound, or a minimum of 46,000 walleye total. The stocking would not occur in a given year if fall electro-fishing shows a large year class of naturally reproduced walleye.
Also, the local fisheries staff will continue to stock the lake with at least 10 percent of the walleye fry raised from the eggs harvested each spring from the lake.
Green Lake will also continue to benefit from an intensive monitoring program. The local crew will continue spring gill netting and fall electro-fishing to keep close tabs on the walleye population and especially, assess the natural reproduction each year.
The management plan aims to "bring back'' the walleye population in the lake. Coahran cautioned anglers at the meeting that the historic high levels of walleye found in the lake during the mid-1990's cannot be achieved by stocking. Natural reproduction is critical for large numbers, he noted.
He said a likely target for the lake would put the walleye population somewhere between the lake's high point in 1995-96, and the low points experienced in the early years of this decade.
Despite the lake's walleye troubles, Coahran said creel surveys conducted on the lake show that those who fish for walleye are still enjoying catch and harvest rates better than found on other, similar class walleye lakes.
But Coahran also pointed out that the number of people who target walleye on Green Lake today, and the total harvest are down significantly. There's been a marked trend towards more fishing for smallmouth bass and panfish in the lake, he noted.
The decline in walleyes is due to a dramatic drop in natural reproduction by walleye in the lake during the last 10 years.
Coahran said predation is one of the biggest factors in this decline. The populations of smallmouth bass populations and more recently sunfish and largemouth bass have grown dramatically during this period.
Northern pike have grown in numbers and size too, in part due to experimental regulations that have now been lifted.
The numbers of perch and crayfish declined during this period.
The reduction in perch and crayfish as forage placed more predation pressure on young walleye. Coahran said perch numbers now appear to be improving, a positive size for the walleye. There are signs that crayfish are rebounding as well.
The lake's smallmouth bass population was already on the rebound when experimental regulations were adopted in 1997 to protect the fish, according to Gilbertson.
Coahran said natural conditions have had much to do with the explosion in smallmouth bass numbers and more recently, both largemouth bass and sunfish. The last 10 years have seen mild winters and hot summers, conditions that favor warm water fish like bass and panfish over cold water walleye.
Anglers play a big role in what is happening as well.
While bass numbers have risen dramatically, their harvest has not. Coahran said fishermen and women kept only three percent of the smallmouth and seven percent of the largemouth caught last year.
In contrast, walleye anglers kept 65 percent of the fish they caught.
Participants at the meeting encouraged the DNR to continue the aggressive stocking program. Fisheries biologist Dick Sternberg had prepared a report for the Green Lake Fishery Project that called for placing a priority on stocking larger fingerlings. The Project was support by a coalition including the City of Spicer and Green Lake Property Owners Association.
Those attending the meeting were vocal in urging a greater harvest of bass from the lake, with some calling for liberal limits of 12 bass. But some were skeptical of the approach: "I don't know how you require people to keep fish,'' said Ann Latham of Spicer.