Tag Archive for "jellyfish"
I found some more depressive news about our oceans. According to an article on discovery.com we are seeing increasing amounts of jellyfish in our oceans. Researchers believe the reason for this is overfishing and global warming.
The amount of jellyfish is a good indicator of how life in oceans change. The larger species feed on jellyfish and when these species are becoming less numerous the jellyfish are able to grow. Jellyfish also compete with other species about food sources like small fish and zooplankton so when there are large number of jellyfish in the ocean it is able to hurt the regrowth of other species.
One other reason that jellyfish is getting the upper hand is the rising ocean temperature as jellyfish are able reproduce for a longer period of time.
The growing numbers of jellyfish has been observed all over the world and especially in parts of the oceans where there is heavy fishing going on, like off the coast of Namibia.
I have also observed unusually large numbers of jellyfish here in Northern Norway. I hope this is a part of their natural circle and not a sign of a failing ecosystem..
This could be some really bad news for the environment in Australia. According an article on cairns.com.au Roger Bradbury, a professor at Australian National University, predicts that if the over fishing at the Great Barrier Reef continues it will turn into a dead zone filled with slimy creatures. He says that the large marine species are keeping in check jellyfish and algae. If the large species were to disappear or the populations are heavily reduced “you get an ocean that’s like swarms of jellyfish, blooms of algae,” Roger Bradbury said.
The professor want to immediately phase out the commercial fishing at the Great Barrier Reef to save the remaining stocks, but of course those who decide are a bit skeptical to stop the fishing. Fishing = big money.
When I read this article I kept thinking about if this could happen here in Northern Norway too. Last year no big shoals of coalfish came into our fjord and that is the first year I have ever experienced that. Some fishermen claimed that this was because there was a big bloom of algae. Could it be that the bloom of algae was caused by over fishing? This spring I have also observed massive quantities of jellyfish swimming around which I find a bit worrying.
I hope this is not a sign of over fishing in my area.
