The Iowa DNR stocks 300,000 to 400,000 trout in Northeast Iowa streams each year. These 50 streams are stocked each week from April through October. More than 600 extra brood trout, weighing over 2 pounds each, are also released in small numbers into each stream.
The catchable stocking program uses rainbow trout. The number of trout stocked into each area varies, depending on length of the stream and how many anglers use the area. These criteria also determine how often each area is stocked.
Surveys show there are still good numbers of trout several days after the most recent stocking and throughout the winter. Along with the stocked trout, many areas have good to excellent numbers of wild brown trout that challenge even the best anglers. Brown trout up to 20 inches are possible.
Trout streams will be stocked unannounced for the rest of the year. There has been no change to the frequency of stockings or the number of fish stocked at any of our trout streams. Moving to unannounced stockings has given DNR fisheries staff more flexibility in completing the stockings and improving efficiency. This has allowed for improved stream access (mowing) and hatchery maintenance, completing projects around the hatchery and planning for stream improvement projects that they otherwise didn't have the time to complete. Almost all of the streams in Northeast Iowa have natural reproduction of brown trout and several have natural reproduction of brook trout. Streams with brown trout reproduction have populations that range from 500 to 2,000 fish per mile that rival driftless streams in Minnesota or Wisconsin.
A small number of trout streams are not stocked in July and August due to marginal water temperatures. This is an annual occurrence.