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Humpback salmon attenuators in Troms and Finnmark

Caught the most pink salmon with a Nordic Steel attenuator

Some call it zombie salmon, others humpback salmon. What is certain is that 29,473 of the unwanted fish have been caught from the Vesterelva river in Finnmark this summer. This river has caught the most pink salmon in the whole country - and the fish attenuator is manufactured by Nordic Steel.

Figures from the Norwegian Environment Agency and the State Governor of Troms and Finnmark now show that the attenuators in the rivers have been very effective. Over 240,000 salmon have been caught in Norway's rivers this summer.

Example of a salmon attenuator in Finnmark. Film: Malin Høstmark Solheim, State Governor of Troms and Finnmark

Nordic Steel has produced so-called spile attenuators for nine rivers, after signing a two-year framework agreement with the State Governor of Troms and Finnmark. The attenuators were delivered before the summer, in time for the fish to enter the rivers.

- "We are very pleased to see that the attenuators are working and that they have caught so many fish. Preliminary reports show that few pink salmon manage to get past the attenuators," says Bjørn Erik Ualand, department manager at Nordic Steel.

Vesterelva in Finnmark (Photo: Vilde Øines Pedersen, Troms and Finnmark County Governor)

Flexible attenuators in aluminum

The Troms and Finnmark state government has developed the attenuators produced by Nordic Steel. They are made of aluminum and consist of guide fences, catch cages, catch cage lids and work platforms. The attenuators are manufactured to be mobile and flexible.

- "We have screwed the parts together, not welded them, to make assembly and disassembly easier. This means that the parts of the attenuators can be changed and moved more easily," explains Ualand.

The pitfalls in Nordic Steel's production

Thousands of pink salmon have been stopped

The fishing attenuators have managed to stop the pink salmon, and local teams and associations are making great efforts to remove the salmon from the attenuators. The Vesterelva river in Nesseby municipality in Finnmark tops the statistics for most pink salmon in the attenuators. But the other rivers to which Nordic Steel has supplied attenuators have also stopped pink salmon.

Humpback salmon (Photo: Lars Åke Andersen)

Number of pink salmon extracted from five rivers with Nordic Steel attenuators:

  • Vesterelva: 29473
  • Lille Porsangerelva: 7893
  • Karpelva: 4001
  • Ytre Billefjordelva: 3572
  • Kvalsund river: 3269

Humpback salmon are removed because they die after spawning and rot in the rivers in the fall. This has a negative impact on both water quality and other species. Humpback salmon can also displace common salmonids and contribute to the spread of disease. An important measure to stop the fish is to set up fish attenuators near the mouth of the rivers. There, the pink salmon are sorted out before they enter the watercourse.

Figures on the number of pink salmon are updated on September 12, 2023 and are taken from: https://www.miljodirektoratet.no/aktuelt/datavisualisering/pukkellaks-uttak/

Nordic Steel-made attenuator in river (Photo: Pierre Fagard)
Fish attenuator in production
Production in Nordic Steel
Fish attenuator during installation in river
Fishing attenuator manufactured by Nordic Steel (Photo: Vilde Øines Pedersen, Statsforvalteren i Troms og Finnmark)

The state administrator in Troms and Finnmark

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