Little Grassy Lake is IDNR's sole catfish hatchery. For catfish, the spawning and fish maturation process requires at least one year, with mature fish spawning on or around June 1; the fish take at least 13 months to grow to a "nonvulnerable" length of 8 inches (20 cm) and are typically ready for delivery to their new homes in July of the following summer. IDNR distributes Little Grassy catfish to 220 separate Illinois waterways.Brenda Garver, "In the Company of Catfish", Outdoor Illinois XV:5 (May 2007), pages 6-8.
