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Fishermen in Southern Norway seek the release of millions of fish into fjords

The juvenile fish will help strengthen the population of coastal cod. Many support financing the initiative through a fishing permit.

"The time is ripe to consider releasing young cod into the fjords of Southern Norway to rebuild the stock," says fish researcher Enrique Blanco Gonzalez.
Jan Arve Olsen
Division of Communication
Presented by: University of Agder
Published

Article summary

  • 80 per cent of respondents support the idea of releasing young cod into the fjords to strengthen the population.
  • Fishermen are concerned about overfishing and climate change as key reasons for the decline in cod stocks.
  • Over 75 per cent believe the authorities should lead a new release programme with scientific support from researchers.
  • A quarter of respondents may be willing to purchase a fishing license for 175 kroner (16 USD) to fund the programme.

This is shown in a study conducted by the University of Agder's Centre for Coastal Research, the University of Tromsø, and the coastal research foundation Fundacion Chinquihue in Chile. 

“This is both surprising and unsurprising,” says the lead researcher behind the study, Enrique Blanco Gonzalez, from the University of Agder's Department of Natural Sciences.

A whole 80 per cent of respondents are positive about releasing young cod into the fjords. 

"It's more than we anticipated. However, it's no surprise that fishermen of all kinds are worried about the current decline in the coastal cod population and want to back measures to remedy this,” he says.

Supportive of new release programme

The main aim of the study was to gain deeper insight into how recreational and professional fishermen, along with the fishing tourism industry in Agder, view the idea of launching a dedicated release programme for coastal cod in Southern Norway.

The fishermen themselves highlight the possibility of preserving fishing traditions in the region by releasing young cod to increase the population.

Researchers also asked fishermen how they think this initiative could be funded and to what extent they would be willing to contribute financially, for example, through a fishing permit scheme.

Overfishing and climate change

The findings reveal that fishermen believe the decline in the cod population has multiple causes. 

They especially highlight industrial overfishing, climate change, lack of food for cod, and declining water quality. 

The least mentioned cause is overfishing due to recreational fishing.

When asked about the potential benefits of a release programme, they said it could primarily help rebuild the cod population. 

They also mentioned opportunities for education and research, strengthening the local ecosystem, preserving fishing traditions in the region, and creating opportunities for fishing and the local economy.

However, the fishermen's main concerns about a targeted release programme are related to potential reductions in genetic diversity among local cod populations, competition for food and space with other fish, and the risk of transmitting diseases to existing wild fish.

"A public responsibility"

Over 75 per cent of respondents also believe that national and local authorities should take the lead in any new release programme.

Furthermore, it should be supported by researchers who can provide scientific expertise.

The same applies to the funding of such a programme. Fishermen expect that the majority of funding should come from the state and local authorities.

Fishing permits 

“Interestingly, one in four people said they’d consider directly contributing to such a programme, for example by buying fishing permits for NOK 175 (16 USD)," says Gonzalez. 

According to the researcher, this shows that there is a willingness among the public to pay for the preservation of coastal cod - even though the majority in the study clearly state that the government should cover the main costs.

Not the first attempt

This is not the first time an effort has been made to increase the cod population in Southern Norway through releases. 

The first time was in 1884 when Captain Gunder M. Dannevig established the Norwegian cod release programme in Flødevigen near Arendal. The programme continued until 1971 and involved releasing millions of small, newly hatched cod fry.

The challenge with the method, however, was that the initial fry stage is the most dangerous in a fish's life, with the lowest survival rate.

Furthermore, it is not possible to mark newly hatched fry, making it impossible to track their survival.

Another initiative took place from 1990 to 1997 through the Programme for Developing and Enhancing Sea Ranching (PUSH). 

This programme laid the groundwork for a new release strategy based on releasing juvenile fish instead of larvae. 

Although these young cod are small, only six to seven months old and 10-12 centimetres long, they can be tagged and monitored by researchers.

"Basis for a new programme"

“Much has happened since then. We now know a lot more about fry production, and we’re much better at keeping fry alive during the crucial early stages of life compared to 30 years ago,” says Gonzalez.

Given the critical condition of the coastal cod stocks in Southern Norway, combined with the positive perceptions and attitudes towards aquaculture-based enhancement programmes seen in this study, the researcher believes it might be sensible to consider launching another comprehensive cod release programme in Southern Norway.

“Of course, it’s not up to me, but the conditions are likely more favourable now than they’ve ever been,” he says.

The potential wild cod release programme in Southern Norway

  • The main idea is to capture wild cod from the fjords in Agder, allow them to breed in land-based facilities where the survival rate is much higher than in the sea, and then release the young cod back into the fjord of origin once they are large enough to have a chance of surviving on their own. This approach ensures they retain the same genetic material as if they were born in the fjord.
  • Given the size of the fjords in Southern Norway and the decline in the cod populations, it is estimated that around 2 million juveniles would need to be released annually on average in each fjord included in the programme. To gather comprehensive data, the programme should span over three generations of mature fish, which is approximately 10 years.
  • A key challenge is the survival rate of cod larvae and fry immediately after hatching. A mature female cod can spawn up to 5 million eggs per year, but in the wild, only two of these typically reach adulthood.
  • Survival rates are higher on land. In the national cod breeding programme by the food research institute Nofima, which focuses on research and development for the aquaculture industry, the survival rate for farmed cod fry was 33 per cent last year, up from 1 per cent in 2003.
  • Researchers believe achieving a similarly high survival rate for wild fish fry may not be feasible. However, they do see significant potential in applying best practices from fry and juvenile fish production in aquaculture to a dedicated release programme for wild fish.
  • They also believe there is potential for learning from what is being done in other countries. Sweden also faces a decline in its cod populations. There, the Baltic Waters research foundation is currently engaged in land-based fry production for the release of wild fish. The project, called ReCod – release of small cod in the Baltic Sea, began in 2020 with a budget of SEK 50 million (about 4.6 million USD) and is set to continue until 2025. It is funded through a collaboration between state, regional and private entities.
  • Similar initiatives are ongoing in Australia and Japan, where they are also advanced in this area.

Reference:

Liu et al. Stakeholders' perception and willingness-to-pay for an aquaculture-based fisheries enhancement program for coastal cod in Southern Norway, Aquaculture, vol. 591, 2024. DOI: 10.1016/j.aquaculture.2024.741111

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Read the Norwegian version of this article on forskning.no

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