In 40 years, the population of cod in the North Atlantic dropped over 95 percent. Will it ever return to its previous bounty?
Since the 16th century, cod fishing has been an integral part of life in the northern Atlantic. It sustained communities with food and livelihood and became rooted in the culture of the area. Yet in the mid-1960s, something happened that disrupted this balance.
Technology hit the fishing industry.
Technological advances such as sonar detectors, frozen food compartments, engine powered fishing boats and bottom trawlers ravaged the Atlantic coast and cod were harvested at exponential rates. In 40 years, the population dwindled to nearly one percent of its former glory.
In 1992, the Canadian government stepped in and declared a moratorium on the cod industry. It was the largest industrial closure in Canadian history. Twenty-two years later, the cod have been slow to restore to their previous bounty. The population is growing, but at a rate so slow, scientists are uncertain it will ever fully recover.
Cod is currently classified as vulnerable on the Red List of Threatened species.
There are a multitude of reasons for this lack of growth. Cod have always been one of the top predators in the northern Atlantic. Their sudden population drop created an unbalance to the food chain. Herring, snow crab, capelin and shrimp (all prey to the cod), experienced a population explosion and their numbers are higher than ever. Now these species compromise the survival rates of cod eggs and fry.
Cod are also sensitive to temperature changes. A change of one or two degrees impacts their behavior and migration patterns. Since the mid-1990s, populations of cod living deeper than 360 meters below the surface have increased by over 90 percent. Although scientists are not sure of the impact on cod’s population growth, they know this pattern is significantly different to its previous behaviors.
Due to the extreme over-fishing that occurred to the cod population, the biodiversity within the species seems to be limited. With the genetic pool restricted and the largest fish being primarily harvested for such a length of time, the chance of true recovery is questionable.