SEARCH
A great gift
for crisis deniers!
Humoring the Horror of the
Converging Emergencies
94 color pages
$24.99 now $15!
Or read FREE online!
Twitter
Ping this story
in social media:
del.icio.us
Digg
Newsvine
NowPublic
Reddit
Facebook
StumbleUpon
|
 |
|
 |
|
 |
|
 |
|
Widely adopted indicator of fisheries health questioned http://apocadocs.com/s.pl?1290353485
The most widely adopted measure for assessing the state of the world's oceans and fisheries led to inaccurate conclusions in nearly half the ecosystems where it was applied.
The new analysis was performed by an international team of fisheries scientists, and is reported in this week's issue of the journal Nature.
"Applied to individual ecosystems it's like flipping a coin; half the time you get the right answer and half the time you get the wrong answer," said Trevor Branch, a University of Washington (UW) aquatic and fisheries scientist.... In 1998, the journal Science published a groundbreaking paper that was the first to use trends in the trophic levels of fish that were caught to measure the health of world fisheries.
The trophic level of an organism shows where it fits in food webs, with microscopic algae at a trophic level of one and large predators such as sharks, halibut and tuna at a trophic level around four.... An example of the problem with the measure is in the Gulf of Thailand where the average trophic level of what is being caught is rising, which should indicate improving ecosystem health according to proponents of that measure.
Instead, it turns out fish at all levels have declined tenfold since the 1950s because of overharvesting.
"The measure only declines if fisheries aimed for top predators first, but for the Gulf of Thailand the measure fails because fisheries first target mussels and shrimp near the bottom of the food web, before shifting to fish higher up," Branch said.
|
|
 |
|
 |
|
 |
[Read more stories about:
overfishing, predator depletion]
|
 |
|
New!:
| |
|
No reader quips yet -- be the first! | |
|
Got a PaniQuip?
|
|
|
We reserve the
right to reuse, remove, or refuse any entry.
| |
|
|
'Doc Michael says:
|
|
|
 |
|
So half the time the cream I'm skimming is at the bottom of the barrel?
|
|
|
|
|
Want to explore more?
Try the PaniCloud!
|
