Fish raised at the hatchery must be spawned at exactly the right time, which varies from species to species. Egg hatching and fish rearing needs also differ according to species. For example, walleye are hatched in glass jars, and trout in plastic trays. Largemouth and smallmouth adult bass are placed into ponds and are allowed to reproduce naturally. Rainbow trout require running water,while other fish prefer standing water. Each species not only favors certain types, but also sizes of food particles. Therefore, both must be matched to the growing fish.
While the last snows of winter still linger, biologists trap the
walleye, a cool water species, and take their eggs and milt (sperm). After
the eggs and milt are taken, the adult fish are returned unharmed to the wild.
The eggs are fertilized immediately with the milt and are placed in glass jars
in the hatchery.
Paddlefish and pallid sturgeon are also hatched in plastic jars in the
Endangered Species building. Once
the fry have hatched, they swim from the jars into plastic tanks, where they are
fed artificial diet. Paddlefish are later released into ponds,
where they grow up to 17 inches in one year on artificial and natural
feed. Pallid sturgeon are kept in indoor circular tanks until they are
tagged and released into the wild.
When fish are stocked into the wild, they must
be transported from one mile to over 1000 miles. We have several trucks
that are capable of hauling fish, with each truck having a tank, and aerator,
and an oxygen system.
