Calamar gigante -Interview: Dr George Jackon-

Published Tuesday, June 27, 2006 by Spyder | E-mail this post

Y aquí la transcripción exacta del programa de radio australiano The World Today de la cadena ABC, en la que queda un poco más claro el porque de ese crecimiento de la población de calamares gigantes.

The World Today Archive - Thursday, 1 August , 2002 00:00:00
Reporter: Nicky Johnston

JOHN HIGHFIELD: Australians scientists are today offering proof that global warming needs to be taken much more seriously by the Howard government and its friends in Washington. You may recall the pictures of the giant squid found on a Tasmanian beach the other day.That's relevant, because our scientists say the same rising sea temperatures which are causing changing weather patterns and have brought devastating drought to large areas of Australia are also turning the world's squid into much larger creatures, with huge appetites and fast breeding cycles.The scientists say that they've found a 1 per cent increase in water temperature causes juvenile squid to double in size. In some parts of the world squid have already denuded vegetation and taken over ocean environments.As Nicole Johnston in Hobart reports for us, the biomass of all the world's squid is now heavier than that of us humans.

NICOLE JOHNSTON: Global warming and over fishing are environmental disasters that squid love. Their growth rates are tied to sea temperatures, in hot water squid eat more. They don't get fat because they have a protein-based system, and so they just grow large quickly. Recently a giant squid was found in Tasmania, and Dr George Jackson from the Institute of Antarctic and Southern Ocean Studies says expect to see more overgrown squid.

GEORGE JACKSON: The body alone was not far under two metres in length and it took about four people to actually turn it over when we wanted to look at the underside. And then it had a large head with large arms, probably as big as a man's upper arm. They've got eight of those and they've got two large tentacles that stretch out many metres.

NICOLE JOHNSTON: Scientists have discovered the breeding cycle and growth rate of squid is also linked to sea temperatures, which means global warming is causing the squid population to blow out.

GEORGE JACKSON: What's been found out, both with field work and in keeping squids in captivity, is that if you increase their temperature even just a little bit, it can have dramatic changes on how fast they grow and how quickly the mature. If global warming increases the world's oceans in particular areas, we could see an acceleration in squid growth, if there's plenty of food around, and that's the other issue we need.

NICOLE JOHNSTON: Dr George Jackson says squid are moving into regions where heavy over-fishing has left them with no natural competitors.

GEORGE JACKSON: If places have been overfished or the squid have been removed, squids have often moved into those areas and established themselves very quickly. Worldwide there's probably, if you look at the biomass of squid, there'd be more squid that the biomass of humans on the face of the earth.

NICOLE JOHNSTON: Dr Jackson says declining stocks of squid predators like shark, cod and rays is allowing new quick-breeding squid populations to establish.

GEORGE JACKSON: Right around the world, and there's some fairly heavy fishing going on, a lot of stocks have been depleted, so what's been found is if you remove the predators or competitors, it leaves a vacuum that the squid rapidly fill, because they grow so quickly. One example was tuna, in recent years the tuna catch has increased from 2 to 4 million tons (I think it is). By removing that extra 2 millions tons out of tuna out of the world's oceans, it's been estimated there's an extra 20 million tons of squid that are no longer being eaten by those tuna.

NICOLE JOHNSTON: Dr Jackson says in the heavily-overfished Gulf of Thailand, squid have taken over local fish populations. He says if the trend continues the fishing industry will become squid based.

GEORGE JACKSON: I think more people are going to be eating calamari, that's going to happen perhaps. There might not be other things to eat, is what it boils down to. If people are used to eating fish and there's not many fish left, where they once were fishing, they're going to look elsewhere, that's what the world is doing, if sea surfaces or sea temperatures rise.

JOHN HIGHFIELD: Dr George Jackson of the Institute of Antarctic and Southern Ocean Studies in Hobart, with Nicole Johnston.

Labels: Monstruos marinos