Walleye smaller, still productive
By MIKE CORN
CEDAR BLUFF RESERVOIR -- Fisheries biologist Dave Spalsbury delights in the numbers, especially now that the annual rite of walleye-egg collecting is complete.
He's especially delighted in the hatch rate from eggs collected and fertilized along the dam at Cedar Bluff Reservoir.
Overall, Spalsbury said, the hatch rate stood at about 50 percent, ranging from 30 percent to 68 percent. In the wild, that hatch rate is sharply lower.
Collecting walleye eggs is an annual springtime event, especially at Cedar Bluff where Spalsbury is the fisheries biologist. Eggs also come from Hillsdale Lake.
It's a massive undertaking.
From Cedar Bluff alone, nearly 61.5 million eggs were gathered from ripe females captured in a series of nets along the face of the dam.
That's 513 quarts of eggs, he said, "128 gallons of walleye eggs. That's quite a few. That's essentially two 55-gallon drums full."
This year, the eggs came from smaller females.
"I think last spring we lost some of our bigger fish to harvest," he said of angling pressure
That left the 2010 year class of fish to provide this year's eggs.
"They are 18 to 19 inches long," he said. "They carried us."
That class of fish, Spalsbury said, was able to grow because of water flowing into the lake that year.
"The lake actually came up 5.5 feet," he said.
And there's hope for another up-and-coming class of fish.
"I did see what looks to be a good 2013 class coming up," he said.
Already, fish hatched in 2013 are about 10 inches long.
"They were healthy," he said, noting that fish should be anywhere from 9 to 11 inches long by the end of the year they're hatched in.
That's one of the reasons why Cedar Bluff has a walleye length limit of 18 inches, to ensure there's a strong class of fish able to reproduce.
That strong performance, Spalsbury said, is likely the reason why Cedar Bluff's egg collection depended on the 2010 class of fish rather than the lunkers that might have been expected.
"They worked that over last year," he said of anglers who enjoyed an unusually long walleye spawning season.
He's not trying to suggest there aren't fish to catch in Cedar Bluff.
"The majority of them were legal," he said of being long enough to catch and keep. "But barely."
The big lunkers typically are females.
"They die," Spalsbury said. "I don't know why."
Male walleye typically die off when they're about 4 years old, while females will live to be 8 or so.
That's his justification for keeping the 18-inch length limit.
"Gives them a chance for females to spawn," Spalsbury said.
The eggs hatched will be distributed to other Kansas lakes, and likely some will go to other states in trades for other fish species.
Spalsbury typically doesn't ask for walleye fry for Cedar Bluff, relying instead on natural production.