The Norwegian salmon-farming industry is grappling with what authorities have called an “explosive” growth in sea lice, as the industry continues to struggle with biological issues.
A recent press release from the Norwegian Institute of Marine Research (IMR) said sea lice numbers have never been higher in northern Norway than they are now.
“In the north, we saw an explosive increase and doubling of the number of louse larvae this summer,” IMR Researcher Anne Dagrun Sandvik said.
Certain areas of Norway saw massive increases in sea louse larvae, IMR said. Production Area 12 saw its sea louse larvae levels jump to levels many times higher than seen in the last three years, and while other areas were not quite as extreme, many northern areas saw higher than normal lice levels.
Sandvik placed the blame for the explosion in lice production on warmer water and said salmon farmers measuring the temperature in the north at a depth of 3 meters found temperatures to be much higher than normal.
“The temperature at 3 meters has been 3 to 4 degrees [Celsius] above what is usual in the north, which has given the lice a huge advantage,” she said.
At higher temperatures, sea lice life cycles progress faster, allowing lice to become adults sooner and multiply, IMR said.
“This, in turn, leads to more lice, both adults and young, at the same time,” IMR said.
The increased lice levels come as Norway is already facing challenges with ...
