Cod and haddock populations have multiplied over past 20 years
Published: 01.04.2020 Updated: 03.07.2020
North East Arctic Cod, also known as skrei, and haddock live rather similar lives. These two species of codfish both spawn off the coast of northern Norway, although the haddock spawn further out by the continental slope. Their larvae are then carried by ocean currents to the Barents Sea, where they mature into adults.
Clampdown on illegal fishing
Norway and Russia, which share the Barents Sea between them, had problems with illegal fishing in the 2000s.
“The authorities took action and managed to combat the illegal fishing. This reduced the fishing pressure on these species in the Barents Sea”, says Edda Johannesen, the scientist responsible for haddock stocks at the Institute of Marine Research (IMR).
In addition to combating illegal fishing, the Norwegian and Russian authorities also drew up long-term management plans for the species, and meanwhile stricter European-wide rules were introduced on landings from foreign vessels.
‘Golden year-classes’ still out there
Around the same time, a number of fortunate coincidences took place. Good spawning seasons, favourable conditions for eggs and good current conditions led to strong year-classes of both haddock and cod in 2004, 2005 and 2006.
“Cod reach sexual maturity when they are seven years old, and haddock when they are six. So it’s important not to fish them before they become sexually mature”, says Bjarte Bogstad, who is responsible for cod stocks at the IMR.
That was exactly how it turned out. The reduction in fishing pressure gave the three ‘golden year-classes’ a chance to reach adulthood.
“Not many cod survive past the age of 15, but a few of the fish from these year-classes are still out there. That’s why people occasionally catch a giant cod”, says Bogstad.
Tenfold increase since the 1980s
The two things that happened in the 2000s gave an important and much-needed ‘vitamin boost’ to two stocks that had been in serious trouble just a few decades earlier.
“This is a great example of fisheries science being put into practice. Saving something now in order to get it back in a few years later isn’t always easy, but in this case we managed it”, says Bogstad.
In the early 1980s, the cod and haddock populations were at record lows. But in the 2000s, both stocks recovered to reach record highs. The haddock population was around 1.2 million tonnes at its biggest, while the cod population was 4.4 million tonnes.
“At the maximum, there was 17 times more haddock and six times more cod in the Barents Sea than in the 1980s”, says Johannesen.
Back to a more normal situation
Since then, the populations have fallen again. In 2019, the haddock population was estimated at 700,000 tonnes, while the cod population was around 2.6 million tonnes. Researchers have observed lower recruitment in both species, but the 2016 year-class of haddock is looking promising.
“Now we’re back to a more normal situation, but still a good one”, says Bogstad.