The World Oceans Now 70% Shark Free 178
wheresjim writes "According to a study published in The Proceedings of The Royal Society, the world's oceans are now about 70% shark free. This is a bad sign for the sharks, the oceans and of course, journalists during slow news cycles."
If I recall... (Score:4, Informative)
http://www.bigmarinefish.com/sharks.html [bigmarinefish.com]
Da da. Da da. Da da.....
(Sorry sharkies.)
Re:Bad for all of us (Score:4, Informative)
About a minutes googling confirms that the Spanish fleet gets over half of the total EU fishing subsidy, while the British fleet gets about 5%.
(Incidentally, British waters contain about 40% of the fish. I (am English and) reckon we should quit the EU ASAP.)
Apart from that, I agree with you.
Justin.
Or read the abstract? (Score:4, Informative)
See online journals of the Royal Society [royalsoc.ac.uk] -- it can be found under Proceedings of the Royal Society B:Biological Sciences titled "The absence of sharks from abyssal regions of the world's oceans".
Re:Yes but... (Score:5, Informative)
What the study found was that below a certain depth (2000 metres) there appear to be no shark species, even though the typical shark prey extend down to much deeper than that. So, while the researchers had assumed that sharks would move throughout the water column, and more species of depth-loving sharks would be found, none were below about 2000m.
This means that all current known shark species exist in only 30% of the total ocean volume (over 70% being below that 2000m depth). Which means that they are all in close proximity to humans and human fishing activity. Which means that they may be more susceptible to overfishing of that area, since they seem unable to spread to lower ocean levels (the so-called abyssal region) to find more food sources. The linked article suggests that there might be a lack of food sources at lower depths, but another summary I saw mentioned the presence of fish species below this depth - which might indicate that either the fish are in too low a number to sustain the sharks; the sharks are incapable of going to the lower depths due to physiology; or they can't compete with other predator species at those depths (eg. squid?).
Of course, other studies have indeed shown declining shark populations, and decreasing sizes of adult sharks of various species (such as white pointers and whale sharks) which indicates that there is increasing pressure on shark populations by overfishing of both them and their food sources... but this study didn't look at that.
Are there fewer sharks than before?? (Score:3, Informative)
But maybe shark's CAN'T live at these depths due to the lack of light and high water pressure? Most fish in the abyssal zone are pretty bizzare, including the Deep Sea Angler [ramseydoran.com]. Why aren't people worried that goldfish aren't down there?
And the whole "70% shark free" calculation is based on the fact that 70% of the ocean's volume is below 6,560 feet.
In conclusion, it's nice to know that sharks do not live at the great depths of the ocean, but there's much to learn about that environment before one can form a relationship between that fact and overfishing.
Re:Bad reporting (Score:5, Informative)
Only the Slashdot artcile has the "Now 70% Free" spin.
Once I noticed this and reread the article, it made a lot more sense -- but it's still a crap article. There's no mention of who the international team of scientists that conducted the study are, and therefore no connection with the scientist quoted and the study. It seems as if the quoted scientist used his opportunity to be quoted in an article to express concern about a real problem, overfishing, without actually knowing about the study itself. Unfortunately the writer took this spin and put it into the opening paragraph and completely threw off the importance of the study.
What really seems to have been discovered is that there aren't sharks 5,280 feet below sea-level. The original study suspects this is because there's no fish to eat down there, which is a pretty obvious fact considering there's no light down there and very high water pressure. And considering 70% of the world's ocean mass is below 5,280 feet, therefore sharks are not in 70% of the ocean.
Re:Yes but... (Score:3, Informative)
Grab.
Re:The other 30% (Score:3, Informative)
Re:Bad reporting (Score:3, Informative)
There ARE fish there, but not in enough numbers to sustain sharks. Check here [pbs.org], or even better, see David Attenburoughs fantastic series The Blue Planet [bbc.co.uk].
if the farmed fish didn't taste weird (Score:3, Informative)
Farmed salmon taste a bit like corn. Hmmm. Any guess why that might be?