KDWP BIOLOGISTS HARVESTING WALLEYE EGGS
Biologists from Canada observing; eggs being propagated on site at Cheney
PRATT -- One of Kansas’ most popular angling opportunities is just beginning as walleye move into shallow, rocky areas -- usually rip-rap along the face of dams -- to spawn. As waters warm and days grow longer, walleye abandon deep water and migrate to these spawning beds, pulling anglers out of their beds in pursuit of this popular sport fish.
But anglers aren't the only ones after walleye. Fisheries biologists have begun their annual harvest of walleye eggs, a process that makes Kansas walleye fishing possible. This year, Kansas Department of Wildlife and Parks (KDWP) fisheries biologists have or will place nets at four Kansas reservoirs to catch spawning females that provide eggs for the department's walleye hatching program. Egg-taking began on March 15 at Cheney Reservoir, March 21 at Hillsdale Reservoir, and March 22 at Cedar Bluff Reservoir. Egg-taking is scheduled to begin March 28 at Milford Reservoir.
Biologists will work night and day for the next few weeks collecting walleye eggs that eventually bring this popular sportfish to lakes throughout the state. Two developments will make this year's walleye egg harvest particularly interesting.
The first is that egg-taking and propagation are being performed on site at Cheney. Biologists are taking eggs from the lake's females, fertilizing them, and placing the eggs in heated hatching jars under the Law Enforcement Division's covered dock. After the 10- to 14-day incubation and hatching period, the young walleye fry will be returned directly to Cheney Reservoir. Ordinarily, the eggs would be taken to one of the agency's hatcheries for incubation and the fry distributed around the state as needed. However, Cheney is infested with white perch, and biologists don't want to risk spreading this undesirable species to other lakes.
Fall test netting revealed a large population of big walleye, indicating that the lake's 21-inch length limit is working. KDWP did not want to let this valuable resource dwindle, so the on-site propagation project was devised. The goal is to stock 15 million home-grown walleye in Cheney this spring.
The second interesting development in this year's walleye egg harvest will be the presence of biologists from Quebec, Canada. Two Canadian fisheries biologists who work for a private firm managing a large lake in Quebec learned about Kansas propagation techniques from a video clip on the KDWP website, www.kdwp.state.ks.us. Because they have no artificial propagation program of their own, they were intrigued and contacted KDWP's Fisheries Section, obtained permission to translate the clip into French, and presented it to their investors. After lengthy conversations, they decided to purchase a walleye barge much like the one used by KDWP. To learn more about the process, they will help with Kansas egg-taking this spring, working for a week with biologists at Milford beginning March 28. They are also interested in setting up an on-site propagation operation much like the one being used at Cheney.
KDWP's statewide harvest goal for 2006 is 100 million walleye eggs and 15 million saugeye eggs. Because fewer than 5 percent of eggs normally hatch in the wild, artificial spawning and hatching is used to increase egg survival rates as much as 40-50 percent. When hatchery-bound eggs reach their destination, biologists monitor incubation closely. Water flows are checked to ensure constant but controlled movement. Water temperatures and oxygen content are also routinely checked. Dead eggs rise to the top of the jars and are siphoned off each day. At 60 degrees, hatching generally occurs on the eighth or ninth day of incubation. As the fry break out of their egg cases, they are carried upward by the water into large circular holding tanks where they are held for two to four days. Then, they are ready for stocking.
Some fry are stocked in hatchery ponds to be raised to fingerling size and stocked later in the summer. Others are stocked directly into lakes as fry. All this activity may not be high-profile, but it means more fish in the frying pan for Kansas anglers.