In the depths of an Iowa winter some fishermen descend in their own version of hibernation, seeding our lakes and streams to only the hardiest of anglers.  But inside an Iowa DNR hatchery, a team of fishery experts is giving every Iowans a reason to rediscover cold weather angling. 

On a crisp winter morning near Manchester, DNR staff wade through a series of outdoor raceways.  Each concrete channel houses hundreds of adult rainbow trout.  By mid-January, this batch of rainbows has reached a fertility climax as the ripe females swim with bulging egg filled bellies.

The freshly plucked fish are shipped inside to build what DNR staff call the backbone of Iowa's trout program.

Dave Marolf: What we do in a controlled environment here at the fish hatchery is a great improvement on the survival that we could expect in the same process that occurs naturally in our streams.

The females are temporarily dipped into an anesthetic bath before staff firmly massage their bellies into a steady stream of golden eggs.  Male trout are then utilized to fertilize those same eggs.

Dave Marolf:  Once water is added to this mixture of semen and eggs, fertilization occurs within seconds.  There are literally billions of sperm cells in this mixture.

Fertilized eggs rest in trays for 30 days under a constant flow of 52 degree water.

Dave Marolf: That is called the eyed eggs stage, when you can see the eye through the eggshell you know you can handle the egg without damaging the developing embryo.  That's when we first look at these eggs again.

The process is repeated over and over to create a staggering number of fish, more than 250,000 trout for Iowa's aquatic ecosystem.

Dave Marolf: We pick out any white, dead, organic matter.  These are some eggs that have died during the incubation process.  There's some eggs that were never fertilized.  But all of the white has to be picked from these eggs.

The fertilized eggs of January 2013 will be half pound trout in 2014.  At that stage, the DNR raised fish will be released into nearly 50 northeast Iowa streams and increasingly into urban lakes around our state.  To witness the reach of Iowa DNR's urban stocking program, just take a look at how far the staff will travel.  In this case, more than five hours and hundreds of miles from the Big Spring Hatchery in northeast Iowa to Council Bluffs on the Missouri River.

Wayne Wingert: We usually start loading early in the morning, get them loaded on and then the fish fall really well.  As long as you can keep the temperature and the oxygen on the fish then they'll haul a long time, stay on the truck and look really healthy.

After opening up a slice of big lake in Council Bluffs, 1,000 rainbow trout are pumped underneath the frozen surface. 

Bryan Hayes: The whole state of Iowa is cold water at least six months out of the year so from mid-October to mid-April we can bring trout into places like Council Bluffs and create that fishing we're looking for.

Families of experienced and first-time fishermen have been waiting all day for a chance to catch a fish found more often on the other side of Iowa.

Wayne Wingert: The truck was 48 degrees and we'll see what the lake is.  You don't want the temperature difference between the two to be too drastic or it can be hard on the fish.  Right at 40.

According to the Iowa DNR, urban stocking rose from just three ponds 25 years ago to 16 quarries, ponds and small lakes this winter, each one bringing trout directly to the people of Iowa.

John Batt: It has taken pretty good hold as far as people getting out and getting the trout stamp and using the facility.  I think the DNR officials have said that it increased tremendously the first two years.  I think it quadrupled because you didn't have the trout fishing on this part of the state.

Those first-time winter anglers can use that annual trout fee to head to northeast Iowa in the spring, summer or fall.  In the meantime, thousands of people who may never have fished or tasted trout are hooked for years to come.

Bryan Hayes: We love to see the kids come out.  We encourage parents to bring the kids out, expose them to fishing.  Kids gravitate naturally to it.  They have a ball.  The trout provide an easy fish to catch for kids and it's a big part of the program.