By Greg Bennett
A media tour of Cooke Aquaculture facilities in New Brunswick offered reporters a crash course on the process of farming salmon last week.
Reporters from Digby and Shelburne, two communities the company has big expansion plans for, toured open net salmon farms as well as a processing plant, net repair facility, hatchery and brood stock facility. This story highlights the beginning of the process.
The Oak Bay Hatchery, located in the extreme southwestern corner of New Brunswick, is one of Cooke’s most critical sites for egg production and broodstock development and protection.
Here, nestled in a quiet wooded area, the company’s future lies in rows and rows of cream-colored trays that carry between 10,000 and 15,000 eggs. Those eggs are stored, fertilized and nurtured at the hatchery until they grow into smolts.
Timing of when eggs are fertilized and how fast they grow into smolts is at least partly controlled by operators at the site through manipulating water temperature. There are critical junctures along the way …like “first feeding” but it can take as little as nine months from egg to ocean.
In the wild, less than 10 per cent of a salmon’s eggs would be expected to survive to the smolt stage. At the Oak Bay facility the target is over 70 per cent.
Besides the millions of eggs and little fish at the facility, the 2,200 fully grown broodstock housed there represent the “best performing” families of fish and are kept and bred until the following generation of carefully selected fish take over the job.
Oak Bay Hatchery Manager Brian Donnelly keeps a close eye on his charges, large and small. He lives about a stone’s throw from the facility, which is constantly staffed, monitored and wired, with alarms. The response is quick if any problems arise.
Everywhere within the hatchery there is evidence of “bio security” measures. Company officials say little is left to chance and every effort is made to guard the young salmon from disease.
Before you walk into the facility, visitors and employees wash their hands and then step into a tray of water and anti-bacterial solution. These shoe wash trays and hand wash areas are stationed in critical areas throughout.
For the millions of little fish within the hatchery, fresh water is lifeblood that surrounds them and huge amounts are constantly being recirculated.
Donnelly says water from the fish tanks is pushed through a process in which solids, ammonia and carbon dioxide are filtered out before being pumped back in.
The goal is to re-use as much water as possible while keeping quality high. Even with a nearly 97 percent recycle rate of water, about 1,000 litres of new water is required every minute to keep all the systems flowing.
The site itself is a mish-mash of old and new technology as it has been built up from the bones of an older hatchery. Company officials say the hatchery they have planned for Digby County will be a more modern version of the New Brunswick facility.
That planned hatchery is hoped to supply all the fish for Cooke’s farms in Nova Scotia, including those in Shelburne County. Company officials say they are still identifying and evaluating potential sites within Digby County for that facility.
One of the critical factors for a new hatchery site will be the availability of fresh water.