Were salmon-killing jellyfish produced by global warming?
The appearance of a massive swarm of jellyfish, and their subsequent decimation of an Irish salmon farm, are this week being blamed on global warming.
Stock worth £1million were suffocated in their cages by the swarm, which is estimated to have covered 25 square kilometres of sea and been up to 10 metres thick. The fish farm's director said “It was unprecedented, absolutely amazing. The sea was red with these jelly fish and there was nothing we could do about, it, absolutely nothing.” says Northern Salmon Company managing director, John Russell (Telegraph). The full story is on The Great Beyond.
This isn't the first time climate change has been linked to jellyfish outbreaks. Last summer, the same jellyfish (Pelagia notiluca) was spotted in unusually high concentrations in the Mediterranean, again prompting speculation about impacts of sea temperature rise (New Scientist). Reuters reported that a volunteer campaign had removed eight tons of jellyfish from the Spanish coastline. Both reports mention temperature and decline in predators as causes.
A recent study linked increasing populations of jellyfish in the North Sea to climate change and predicted that more jellyfish would appear over the next 100 years.
If the two events are truly linked the UK's salmon industry may have to be added to the list of climate change victims.
Image via Wikipedia
Daniel Cressey and Anna Barnett
Comments
In October 1945 I returned from UK to Australia on a ship named Andes via the Indian ocean.
I was impressed by the day after day vast and I mean vast number of jelly fish.
It now occurs to me that these jelly fish contribute to turbidity of the water thus reducing the depth of penetration of IR radiation.
This would cause an increase in surface temperature.
The experience with solar ponds tells us that IR penetrates at least two meters of clear water before being collected on the floor of the pond.
IR being infra red radiation.
In the turbid water of some farm dams only the top few inches of water is heated.
Posted by: Stringer | December 3, 2007 09:39 PM