Lake Sturgeon Hatchery Production and Black Lake Stream Side Rearing Facility
In recent years many changes have been implemented in lake sturgeon culture. There is consensus among fisheries managers that hatchery supplementation will be an important part of lake sturgeon restoration plans, new methods of sturgeon culture are being used throughout the upper Great Lakes basin. Traditional hatcheries rely on ground water for incubation and rearing.
Traditional Hatchery
Mobile Hatchery
Stream-Side Hatchery
Managers are increasingly relying of stream-side trailers and more permanent stream-side hatcheries for sturgeon production. Managers believe that rearing eggs and larvae during informative early life stages is important to allow individuals to ‘imprint’ on streams they will be released in. Because lake sturgeon may not reach sexual maturity for 15-20 years, caution is warranted when implementing restoration strategies to ensure fish will return to the streams in which they were released.
Michigan State and Michigan DNR Researchers Collecting Eggs and Sperm
Use of Stream Water Sources is Important
- Water is pumped from Kleber reservoir on the Black River to the stream side rearing facility
- Intake was moved mid June, from near shore (1-1.5 m depth) to main river channel (3-4 m depth)
- Domestic lines were added when hatchery temperature exceeded 25oC
Stream water must be filtered to remove sediment which can be harmful to fish eggs and larvae
- Two stage filtration
–3, 100 micron sock filter
–3, 50 micron sock filter - UV Filter for egg incubation period
Egg mortality is significantly reduced when using UV sterilization of water.
Fertilization and Incubation
- Eggs are maintained in trays or jars with constant fresh water added through the incubation period.
- Eggs become ‘sticky’ when they come in contact with water. Clay or other compounds must be used as a de-adhesive measure.
- Each half sibling family is kept separated.
- Routine formalin treatments to reduce pathogens.
- Mortality is monitored daily.
Larval Rearing
At hatch the larvae have no developed mouth or eyes. They use their large yolk sac for nutrients for the first weeks to grow and develop sensory capabilities.
After larvae have used their yolk sac reserves they are fed brine shrimp.
Hatched larvae are kept in small aquaria with cover provided.
Following emergence from cover, the larvae are retained in the small aquaria until they are feeding freely. Then they are transferred to larger tanks.
Main Hatchery
When larvae are feeding well, they are taken to other sections of the hatchery where they are maintained in larger tanks or raceways. Juveniles will be kept in these tanks until they are released in late summer. Some experiments have been conducted where individual larvae were housed in small cups.
