Thursday, December 2, 2010

UNH Experts Visit Nova Scotia Aquaculture Operations

Tanks used to raise Halibut at Scotian Halibut Limited
Professor Hunt Howell, Jonathon Bunker, and I recently traveled to Nova Scotia, Canada, to visit several commercial aquaculture businesses. Our first stop was at Scotian Halibut Limited where Atlantic Halibut are produced from captive brood stock located at their Wood Harbor facility. 

After spawning, the eggs are hatched and grown in a large, 5-ton silo tank for several months. Next step is the nursery where they slowly grow to about 30g in one year. Juvenile halibut are then sold to land-based grow-out facilities throughout Canada and the United States. 

A portion of the juveniles are sent to Scotian’s grow-out farm in Clarks Harbor. Here they are raised to 5kg or larger and sold to restaurants or used as future brood stock. According to Brian Blanchard, General Manager of Scotian Halibut, Scotian has begun a a new study in which water from the grow-out system circulates through heavily aerated tanks of red macro algae. 

The nutrient-rich water, intense lighting, and movement of the algae in the water column allow it to double in size in 3-4 months. The algae acts as nutrient scrubber, absorbing effluents from fish waste before recirculating back through the grow-out system.

The second company visited was Cold Water Fisheries, one of largest producers of Rainbow and Steelhead trout in North America. We toured two of their sea-based farms, one in Liverpool and the other near Pubnico. Each site has approximately 20 floating cages stocked with 30,000 Steelhead trout. Operational Manager Sherman D’Entremont said they use several hatcheries in Nova Scotia and PEI to hatch and raise the trout to 100g before transferring them to the sea cages. The trout are typically grown to 2-3kg and sold mostly to markets in Canada. They are currently producing more than 3500 tons of trout per year
Floating cages in Nova Scotia where steelhead trout are raised.

Visiting fish farms provides important learning experiences for scientists. It allows us to meet the farming community and learn about their hardships and accomplishments. With this knowledge, we can better prepare research proposals that will help build a strong aquaculture industry.

-Mike Chambers, UNH Cooperative Extension

No comments:

Post a Comment