(Spirit Lake)--The Iowa DNR is conducting surveys of the fish population in the state’s lakes and streams. Fisheries Biologist Andrew Carlson with the Spirit Lake District Office says the surveys are conducted three times during the year.

Carlson says they use different methods depending on the time of year.

He says surveys of the walleye population about four years ago led to changes in the slot limit on the Iowa Great Lakes.

Carslon says the change has been beneficial to the Walleye population.