Inch River Hatchery - Background Information

Overview

Inch Creek Hatchery uses modern fish culture techniques to produce coho salmon, chinook salmon, chum salmon, and steelhead trout for a number of local tributaries to the Fraser River. We are located near Mission, British Columbia, Canada. The project was conceived and constructed (from 1981 to 1983) as a satellite facility. This means that broodstock is collected from a number of local streams, eggs are incubated and juveniles reared at the hatchery, and then fry or smolts are released in their stream of origin. The facility uses groundwater exclusively, pumped from shallow wells.

The hatchery currently produces 600,000 coho smolts from Inch Creek, Norrish Creek and Stave River. In partnership with community-run hatcheries about 150,000 coho are also raised for the Nicomekl and Serpentine Rivers in Surrey. In addition the facility produces 200,000 chinook fry from the Stave River and 20,000 from Maria Slough; 20,000 steelhead smolts for the Stave River; and 1,000,000 chum fry from Inch Creek.

Cycle of Activities at the Hatchery

From October to December 20,000 or more coho and chum salmon return to Inch Creek. Thousands of these fish can be seen spawning naturally. The majority of Inch Creek returns are directed into concrete channels where they are sorted for hatchery eggtakes or harvested by First Nation's fish buyers. Throughout the Fall and early Winter adult salmon are captured from other local streams, transported live to the hatchery and held in concrete raceways or fibreglass tubs until sexually mature. Eggs are stripped from ripe females and fertilized with milt from mature males.

Incubation starts inside the main hatchery building. The incubation room is closed to the public because eggs are sensitive to temperature changes, light and mechanical shock during discrete phases of their development. The rate of egg development is determined by water temperature. After about 6 weeks of incubation on warm well water chum and chinook eggs reach the `eyed' stage where large, black eyespots are easily visible.

At this point chum eggs are transferred to keeper channels. These shallow concrete raceways have a single layer of clean gravel. The eggs are placed on screens over the gravel and the keepers are covered to protect the eggs from sunlight and predators. When the eggs hatch into alevins they drop through the screens and complete their incubation in the gravel. Each alevin relies on a large yolk sac attached to its belly for nourishment. When the chum alevins have used up their yolk sac and become free swimming fry they migrate downstream to the deep concrete raceways. Here they are hand fed for 2 to 3 months before release to the river.

Chinook and coho complete their full incubation term in trays inside the incubation room. They are then transferred to small aluminum containers or fibreglass tubs where they are hand fed. Chinook are ponded in late January and released when about 5 grams weight in May.

Coho are incubated on chilled, re-circulated water. The use of cold water extends the coho incubation period until late June. Like the chinook they are first reared in small aluminum containers or fibreglass tubs. When about 2 grams in weight they are transferred to the deep concrete raceways and reared for another year. Coho are kept at the hatchery for a total of 18 months. For example coho eggs taken in 1998 are released as 21 gram smolts in May of the year 2000.

Steelhead are transferred to the hatchery from the Fraser Valley Trout Hatchery (operated by the Province of B.C.) as fry. They are raised until about 100 grams in weight and released in May.

The incubation and rearing program protects fish during the critical fresh water phase of their life cycle. Hatchery fish are released when prepared for the migration to saltwater. Therefore hatchery fish do not compete with their wild cousins for freshwater resources.

Production/Hatchery Benefits

The results of the hatchery program are carefully monitored by an annual marking program. A proportion of all fish are tagged before release by implanting a coded-wire-tag, 1 mm long, in the nose cartilage. The majority of hatchery coho are also identified by removal of the adipose fin. Recovery of the CWTs allows for statistical analysis of harvest and survival rates. Identification of hatchery coho also permits selective fisheries to protect wild coho.

The latest data available indicate the following juvenile to adult survival rates for hatchery releases: Chum - 1.3%; Coho - 5.2%; Chinook - 1.4%; Steelhead - 4.0%

Releases

Annual fish releases are available through either the Mapster project, or through a query to the release database