Historic Waskish Hatchery 1941–1979

Historic Waskish Hatchery 1941–1979. . , As far back as 1927, walleye eggs were harvested at the mouth of the Tamarac River. Eggs collected here were sent to the State Hatchery at Redby for hatching until 1941 when the Waskish Hatchery was built as a Works Progress Administration project. The last harvest at the Waskish Hatchery was held in the spring of 1979., The Waskish Hatchery was not built or operated to sustain the Red Lake walleye population. Natural reproduction of walleye in Red Lake are more than adequate. The Red Lake walleye hatched here were used for stocking needs elsewhere in Minnesota, as well as being shipped throughout the United States., Today's hatchery technology is very similar to that of the late 1800s. The hatchery utilizes a small portion of the eggs produced in a lake, incubates them in a controlled environment, and improves the hatch rate substantially. This creates a surplus of fry to be used in other lakes where natural reproduction is lacking. The longstanding policy of returning a portion of the hatchery fry back to the parent lake actually results in a significant net gain in overall fry production for the parent lake., Since the volume of eggs at this site was extremely high (hundreds of millions), fry return to Red Lake was also very high., Spawning runs , As spring days lengthen and water temperatures rise, the walleye begin their spawning run up the Tamarac River. This photo, taken in the early 1970s, shows the trapping structure in the river where spawning walleye were captured briefly for stripping. Only mature walleye spawn: females first spawn at about 15-17 inches or 5-6 years of age while the faster maturing males spawn about 4 years of age., Trapping spawning walleye in the mouth of the Tamarac River in the early 1970s, Stripping eggs , Stripping is the common term used by fish culturists for forcibly removing both eggs and sperm from "ripe" fish. "Ripe" refers to that time when reproductive material freely flows from the fish with gentle pressure. Unripe (or "green") females can be held 1-3 days in cribs until they ripen, at which time the eggs are stripped from the fish on special tables at the water's edge., Stripping eggs from a female walleye, Fertilization , Eggs are carefully stripped to minimize contact with water. Sperm stripped from males is added to eggs in a pan, then mixed to thoroughly contact as many eggs as possible. Most fertilization occurs in the first 15 seconds when water (which activates the sperm) is added to the mix. Any eggs not fertilized within 30 seconds will probably not be fertilized., Coating , Eggs are naturally covered with an adhesive allowing them to adhere to pebbly river bottoms or shoreline substrates where running water and wave action oxygenates them. For hatchery incubation, eggs are coated with bentonite (clay) to remove the natural adhesive., Washing and Hardening , Once coated, the eggs are washed in screen boxes to remove the excess bentonite and then gently placed in containers for water hardening. During this process, the soft, very fragile eggs absorb water and swell to twice their size. After about four hours of water hardening the eggs are quite durable and can be safely transferred to hatchery jars., Battery of jars , The jars are arranged on racks called batteries. Here at the Washkish Hatchery there are 4 batteries, each with 120 jars. When full, the Waskish hatchery held about 120,000,000 eggs! Once the hatchery was full, excess eggs were sent to other hatcheries., Incubation , Each jar holds about 2 quarts or 250,000 eggs. The oxygen needed by the eggs is provided by water flowering from faucets down a standpipe to the bottom of the jars. This creates an upwelling flow that gently rolls the eggs, ensuring that all eggs are continuously exposed to freshly oxygenated water. The eggs are denser than water so they remain on the bottom while excess water overflows into the trough., Fry , As the eggs hatch, the fry follow the water flow, swimming up and out of the jar and into the trough where they follow the flow through a series of water pipes into metal fry tanks. The young fry can survive up to three days in the tanks without food by using their yolk sack for nutrition. By weight, one pound is about 100,000 fry. One day old walleye fry are ready to be stocked into Minnesota lakes or rearing ponds.