Top News

Dispelling the arguments against salmon aquaculture


Fish escapes and effects on native wild salmon populations are one of the biggest arguments against Grieg NL by those opposed to the project.

Grieg NL has provided plenty of information concerning new technologies and processes they will implement to deal with fish escapes and impacts on wild populations returning to resident rivers in their environmental assessment (EA).

The EA was registered, reviewed by numerous government departments and released. Yet the armchair critics of this project continue to present ideas that have been addressed in the EA.

There is scientific evidence presented in the nearly 800-page document that addresses all the opponents’ outdated theories. I encourage everyone to read it.

Currently in Newfoundland and Labrador aquaculture companies are introducing salmon juveniles into ocean cage sites at 50 to 70 grams; Grieg has proposed to grow their smolt to a minimum of 300 grams in a land-based nursery before introduction into the ocean cage sites.  Annually Grieg has proposed to introduce four million 300-gram smolt, one million 1,000-gram smolt, 1.5-million 1,500-gram smolt and half a million 1,800-gram smolt.

This will reduce the amount of time the salmon have to spend in the ocean significantly and practically eliminate the chance of “swim throughs.” Those opposed to the project talk about land-based systems, while Grieg NL will be growing their salmon to a larger size on land, in the world’s largest state-of-the-art salmon hatchery.

Combine this with the introduction of the Midgard net pen system by Aqualine AS – 600 systems installed worldwide with no fish escapes to date. One of Aqualine’s cages has even been run over by an off-course vessel and no fish escaped!

Grieg has also proposed to use sterile fish, which have three sets of chromosomes instead of two. Triploids are genetically identical to diploid fish of the same stock. There are many products currently available in the marketplace that are triploid – bananas, blueberries, grapes, trout, oysters, and watermelon. These products have been developed because of their desirable qualities, generally seedless and larger size. Sterile triploids are not genetically modified organisms and are absolutely safe.

A recent paper released by the Institute of Marine Research in Norway, titled “Sterile Escaped Salmon Avoid Rivers,” found, after seven years of genetic testing of nearly 4,000 escaped salmon in 17 Norwegian rivers, that triploid salmon are only one-tenth as motivated to migrate up the rivers as diploid salmon.

This proves that transition to production of sterile triploid salmon has long been considered as concrete action against mixing of escaped salmon with wild salmon populations. Wild salmon can feel quite safe as long as farmed salmon that escape are triploid; they are sterile and will not follow their wild relatives up the rivers.

We are often quick to point the finger at foreign fisheries – Greenland harvested 47 tonnes of Atlantic salmon in 2013 while St. Pierre-Miquelon harvested 5.3 tonnes. Canada, however, harvested 136 tonnes of salmon in 2013 – 59 tonnes for aboriginal harvests, two tonnes for the Labrador resident food fishery and 75 tonnes during the recreational fishery. This does not include salmon caught by poachers or those that died as a result of hook-and-release fishing practices.

One can clearly see that the largest threat to Atlantic salmon returns in Newfoundland and Labrador is not aquaculture but rather the uncontrolled wild fishery, poaching and genetic pollution.

There has been no undisputed evidence to date of direct effects of salmon aquaculture on wild populations, even though Atlantic salmon are the most commonly produced saltwater species and have been cultured worldwide for many years.

Leon Fiander

MSc. environmental science

Marystown

Recent Stories