Friday, January 11, 2008

DEATH AT THE FISH FARM

Pretty in the water but nasty up close. This is Pelagia noctiluca or the mauve stinger jellyfish which grows up to 10 centimetres wide. It's also sometimes called the nightlight jellyfish because it produces a blue-green luminescent mucus.

Last year, a swarm of baby stingers, 26 square kilometres in area and 10 metres deep drifted into a salmon farm in the Irish sea and killed all 100,000 fish. The babies were small enough to be swept into the cages by the currents. This jellyfish is a Mediterranean species but has been seen along the British coast as far north as Shetland.

Scientists are putting this down to the warming of the winter sea water. Overfishing is killing off the natural enemies such as sunfish, trigger fish and loggerhead turtles that eat the jellyfish. And the jellyfish don't make shells so no carbon dioxide is absorbed from the ocean.

I've blogged about fish farms before and these jellyfish are part of a vicious circle. To feed people, fish farms are needed, fish farms are needed because of overfishing to feed people, overfishing means more jellyfish. To make things worse, small plankton-eating fish which compete with jellyfish and keep the numbers down are also being over-fished.......to make fishmeal to feed the fish in fish farms.

9 comments:

R.H. said...

It's quarter past one and I've got a new monitor.

Diamond View, that's what it's called.

And golly, it is so clear, I'm seeing Darcy's handprints on Miss Laura for the first time.

R.H. said...

Why do you have no links?

Who do you think you are, King Blog?

You are not!

R.H. said...

I'v got a new blogpal, Lexicon Harlot.

-Robert.

(I don't know what Lexicon means but Harlot rings a bell somewhere)

R.H. said...

No one could replace you Miss Jahteh (my little Jellyfish!!!)

ROBBERT!!!

Brian Hughes said...

"...called the nightlight jellyfish because it produces a blue-green luminescent mucus."

Sounds like my nose on these cold, damp winter mornings.

JahTeh said...

Rh,I haven't got links because I haven't figured out how to do them yet but I'm getting there. I'm still on old blogger and links are easier on new blogger and I haven't got around to that yet either. I've met Lexicon Harlot, she's sharp and funny. The brownie like her too.

Ah, Fleetwood, as opposed to the Rudolph variety you exhibit after closing time.

The Editor said...

Hmmm...

A 19th century Cree Indian Chief is credited as saying:

"Only when the last tree has died,
only when the last river has been poisoned, only when the last fish has been caught, only then will we realise that we cannot eat money."

And I have that on a t-shirt I wear regularly.

JahTeh said...

Gerry, I was reading about a new fish net, can't find it now of course, that lets smart fish swim out of the bottom but the fish they want to catch can't swim downwards so stay caught. If they could all think outside the square like this then trawlers wouldn't have to throw the by-catch back into the sea. I've caught a few episodes of the series on Ten about the crab season in Alaska. As soon as the quota is caught, that's it, season over and all boats home. I can't watch too much, seasick.

Middle Child said...

Bloody hell, and our European friends say we have vicious wildlife