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
|
 |
Posted Tue Aug 30 2011: from
BBC:
|
|
 |
|
 |
|
 |
|
What is killing killer whales? http://apocadocs.com/s.pl?1314713089
Marine experts are concerned about an invisible threat to the animals that has been building in our seas since World War II.
That was when industries began extensively using chemical flame retardants, such as PCBs.
These chemicals were later found to harm human health and the environment, and governments around the world banned their use in the 1970s.
But their legacy lives on in the world's seas and oceans, say biologists, posing a modern threat to animals such as killer whales, also known as orcas....
As large mammals, killer whales consume a large amount of prey.
But this position at the top of the food chain, as "apex predators", makes them particularly vulnerable to changes in their prey.
That is because orca feed on fish that in turn eat polluted prey or absorb pollution from the water. So the orca ingest all of the pollution in the chain, in a process called "bioaccumulation"....
Dr Jepson says this fat solubility is a considerable issue for female cetaceans such as killer whales who feed their young for up to a year on high fat milk to kick-start their development.
"You get this huge maternal transfer. It's been calculated that in whales and dolphins about ninety percent or more of the mother's body burden of PCB can be offloaded, particularly to the first calf," he tells BBC Nature.
|
|
 |
|
 |
|
 |
[Read more stories about:
PCBs, predator depletion, toxic buildup, flame retardants]
|
 |
|
New!:
| |
|
No reader quips yet -- be the first! | |
|
Got a PaniQuip?
|
|
|
We reserve the
right to reuse, remove, or refuse any entry.
| |
|
|
'Doc Jim says:
|
|
|
 |
The top of the food chain is only as strong as its bioaccumulated links.
|
|
|
|
|
Want to explore more?
Try the PaniCloud!
|
