The Fish Production Cycle

Raising and releasing millions of fish each year requires involved and dedicated work. The following is a summary of the work that goes into spawning, raising, marking, and releasing fish at Makah National Fish Hatchery.

Coho salmon egg larvae

Spawning

The fish raising cycle begins with the return of the adults to the hatchery in the fall and winter.  The adults remain in holding ponds until they are mature enough to spawn.  During spawning events, we sort the fish based on species, maturity, and sex.  Afterwards, we remove the females' eggs, fertilizing and cleaning them, before placing them into incubation trays.

Incubation

After about 30 days, the fish embryos develop visible eyes, or "eye up". We then safely sort the live versus dead and count these now "eyed up" eggs. About 10 days later, or 40 days after initial fertilization, the "eyed up" eggs hatch into baby fish, known as "alevin". The alevin remain in the incubation trays for an additional 65 days or until they have fully absorbed their yolk sac and become older baby fish, known as "fry". While the time from initial fertilization to the fry stage usually takes about 105 days, the time varies depending on species and water temperature.

Rearing

After the alevins transform into fry, we move them into large tanks, where they're fed multiple times a day. We monitor the fry's growth throughout the year. This involves removing uneaten food and waste and splitting the fry into additional tanks when crowding occurs.  

Marking and Tagging

Most fish are marked and tagged as part of our hatchery evaluation monitoring.  The fin clip marking allows both scientists and the public to identify hatchery vs wild fish.  The tags have a code on them which, when removed from adults, allows our scientists to determine their hatchery and year of origin.  The information collected from these marked and tagged fish help hatchery managers make more informed decisions. 

Release

Hatchery fish are released into the Tsoo-Yess River each spring.   The total time at the hatchery varies between 7 to 16 months depending on fish species, their biology and development, river conditions, and the hatchery management strategy. 

Continual Operations

The following operational responsibilities are carried out throughout the year and at every stage of the fish production cycle.

Water Quality

The water quality is routinely tested for physical and chemical properties such as temperature, oxygen, pH, and nitrates.  Salmon and steelhead have an ideal and livable range for each water quality parameter.  Regular monitoring can help identify potential issues before they become serious health risks. 

Fish Health

Fish health veterinarians watch over the health and welfare of the fish that we raise.   The veterinarians work with hatchery managers to prevent disease outbreaks.  If problems do occur, veterinarians may prescribe disease treatments.  Our goal is to avoid the need for disease treatments, especially the use of antibiotics.  

Hatchery Maintenance

Infrastructure and equipment maintenance plays an essential role at Makah National Fish Hatchery.  A functioning water intake, pumping, distribution, and waste treatment system, for example, is necessary to keep these fish alive at every life stage at this facility.  Emergency situations due to weather, power outages, and infrastructure failure are serious threats to fish production.  Staff are on call after work hours for such emergency situations, including staff housed on site.