Painful for ice bathers and dangerous for farmed fish – news Rogaland – Local news, TV and radio

– There must have been hundreds of short and long pearl Normans I observed on this dive, says Rudolf Svensen, who is a diver and director of the department of natural history at Stavanger museum. Perhaps you have heard of it: Perlesnormanet. – If you do winter swimming, you should take care. If not, it is the farming industry that has the biggest problems, he says. – I tried to touch one two years ago, it really hurt, says Svendsen. Photo: Erik Waage / news Svensen regularly dives at Saltneset on Hundvåg in Stavanger. He sees the jellyfish every time he dives. Friday afternoon was no exception. Some of them swim, while others of them float. The animal itself is small and looks like a kind of cotton ball, and they form colonies that can be up to 30 meters long. Pain for a day – I tried to touch one two years ago, it really hurt. Such a throbbing pain for 24 hours, says Svendsen. He says the pain is much milder than being hit by a jellyfish, but more similar to being stung by a fart. Rudolf Svensen has his underwater camera with him and has documented many species on his dives at Saltneset on Hundvåg in Stavanger. Photo: Erik Waage / news For the diver himself, the jellyfish is not a big nuisance, but for the farmed fish it is a completely different matter. Great danger for farmed fish Fish can suffer great damage from contact with the marine animal. The jellyfish’s nettle threads contain a strong poison that can lead to mortality in farmed fish. Perlesnormanet can cause ice bathers great pain that lasts for a day. For farmed fish, it can be fatal when it enters cages. Photo: Rudolf Svensen / Stavanger museum Waves, turbulence in the sea or physical barriers cause the pearl normanet to split into many small pieces, and can penetrate breeding cages. In 1997, 10–12 tonnes of salmon died at two facilities in Øygarden and Fedje in Vestland. In 2001, 600 tonnes of fish died. – It is these small pieces of the perlesnormanet that can be problematic. If jellyfish with nettle cells enter a cage and hit a fish, the fish can suffer wounds and damage to the gills, says research leader Lars Helge Stien at the Institute of Marine Research. The salmon that died in Øygarden and Fedje had got the jellyfish in their gills, and suffocated. Appearing more and more often The jellyfish often appear when autumn approaches and it is colder in the water. Even those who love to dip their bodies in ice-cold water can have an unpleasant encounter with the jellyfish. – If you are uncritical when you jump into the water, you can hit them. I tell the wife who is bathing that she must be careful. But I think many ice bathers wear shoes. Then it will probably be fine. They should also use a diving mask or swimming goggles to see better what is in the sea, says Svensen. Fish can get wounds and damage to the gills. Year-round bathers can get hurt. For one day, according to Rudolf Svensen. Photo: Rudolg Svensen / Stavanger museum There is now an increasing incidence of pearl Norman along the Norwegian coast, especially in Western Norway. – Have poured in No less than 250 observations were reported in one week to researcher Tone Falkenhaug at the Institute of Marine Research. Tone Falkehaug, Institute of Marine Research. Photo: Erlend Astad Lorentzen / Institute of Marine Research – Registrations have poured in, says Falkenhaug to the Institute of Marine Research’s website. But little is known about the jellyfish, which hurts people and can be fatal for fish. – The nettle cells can burn whether the jellyfish is 5 meters or 30 centimeters long, says Falkenhaug. The pattern for the distribution of the pearled normannet this autumn is similar to the pattern from last year. Observations then picked up sharply in November, but began to decrease from January.



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