AURORA, Colo. (KDVR) — When Paul Winkle says he is gone fishing, it is not what you think. He is not taking them, he’s making them. He is part of the Colorado Parks and Wildlife walleye spawn program and he’s been doing it for 19 years.

“We collect male and female walleye, spawn those fish and collect the eggs,” the CPW aquatic biologist said.

The process begins with carefully catching the walleye in gill nets, taking them to a spawning house, and separating the males from the females.

“All you have to do is put a little pressure on the belly and if eggs come out you know it’s a female and if the sperm, or milt as we call it, comes out then we know it’s a male,” Winkle told FOX31’s Dan Daru.

The female eggs are then fertilized and grown under CPW’s supervision. When they are about a quarter-inch long, they are at the fry stage and able to be released back into specific waters in Colorado.

“Colorado Springs, the Denver area, Boulder County, Larimer County up to the Fort Collins area,” Winkle said.

About 132 million eggs were harvested, 99 million of which will eventually hatch.

“Cherry Creek will receive 4 million walleye fry this year,” Winkle said.

So what is a good excuse if you don’t catch walleye at Cherry Creek State reservoir?

“Uh, you don’t know what you’re doing?” Winkle joked.