Delousing blamed for shrimp decline

One of the fishermen, Ulf Garstad from Trøndelag in Middle Norway, told the paper: “The shrimps are affected. They have been sick, have got smaller in size or have just disappeared.”

He argues that the Norwegian government needs to consider alternative salmon production methods: “It’s my opinion that 20% [of the country’s salmon farms] have to be transferred to shore or closed cages.”

Renee Katrin Bechmann, from the research institute “Iris” in Stavanger, told VG that shrimps do die if exposed to lice treatments in the same concentration as is used in salmon farms.

“We should be cautious about jumping to any conclusions, but the results of our studies show that most shrimps getting lice medicine die," she said.

Contradictory claims

However, in September 2014 Bechmann was interviewed for Kyst.no about the same trial - http://www.kyst.no/nyhet/?article_id=108048 - and said: "We made a worst case scenario. In natural conditions in seawater the pharmaceutical probably would be diluted”.

The compound they studied is the feed-based agent teflubenzurone. She also said that they would like to set up a new trial, using a more natural regime and levels of teflubenzurone. How this work is progressing is not known. Kyst.no has so far unsuccessfully tried to reach the researcher for further thoughts.