jimoran
2005-11-08 19:52:16 UTC
Back to Story - Help
Seals, Sea Lions Can Be Condor Food By RANDOLPH E. SCHMID, AP Science
Writer
Mon Nov 7, 9:02 PM ET
The growing populations of harbor seals and sea lions along the West
Coast may be good news for California condors.
While condors are now best known for eating dead deer, cattle and other
animals, new research shows that carcasses of marine animals once
formed a large part of their diet. Some condors are already finding
food in sea lion and seal rookeries that have been growing along the
coast, reports Stanford University researcher Page Chamberlain.
A large part of the condor's current diet is dead animals provided by
conservationists, said Chamberlain, a professor of environmental
science.
"We need to find a natural food source," he said, and the marine
mammals could be it.
Condors will eat whatever they can find, he explained, and once they
find a source of food they will continue to fly over the area looking
for more.
To help reintroduce them to the seals and sea lions some young condors
are being raised in pens near the marine mammals breeding ground. When
these are released they know of this source of food and others will
follow them there, Chamberlain said.
Chamberlain's research team has studied what condors were eating over
the last 10,000 years. They determined the diet by comparing the
amounts of carbon and nitrogen in feather and bone fragments over time.
Their findings are reported in Tuesday's issue of Proceedings of the
National Academy of Sciences.
At one time California condors ranged across the nation from the West
Coast across the southern states and even north to western New York.
The researchers found that 10,000 years ago marine mammals were an
important component of condor diets along the West Coast, while the
birds living inland focused on the abundant large mammals. With the
extinction of many large mammals, condor range was reduced to the West
Coast and the food source from the ocean.
Indeed, Lewis and Clark reported seeing the giant condors feeding on
whale carcasses in 1806 in the mouth of the Columbia River.
In the following years the seal and sea lion population was reduced by
trapping, and condors turned to land animals, particularly cattle which
were then being introduced into California.
Over time, however, condor numbers declined with only a few remaining,
mostly in captivity. With efforts underway to re-establish populations
of wild condors the growing availability of marine mammals along the
coast should enhance their chance of surviving.
The research was funded by the Lucille and David Packard Foundation,
the National Science Foundation, U.S. Fish and Wildlife Service and
Bodega Bay Institute.
___
On the Net:
Proceedings of the National Academy of Sciences: http://www.pnas.org
Copyright © 2005 The Associated Press. All rights reserved. The
information contained in the AP News report may not be published,
broadcast, rewritten or redistributed without the prior written
authority of The Associated Press.
Copyright © 2005 Yahoo! Inc. All rights reserved.
Questions or Comments
Privacy Policy -Terms of Service - Copyright/IP Policy - Ad Feedback
Seals, Sea Lions Can Be Condor Food By RANDOLPH E. SCHMID, AP Science
Writer
Mon Nov 7, 9:02 PM ET
The growing populations of harbor seals and sea lions along the West
Coast may be good news for California condors.
While condors are now best known for eating dead deer, cattle and other
animals, new research shows that carcasses of marine animals once
formed a large part of their diet. Some condors are already finding
food in sea lion and seal rookeries that have been growing along the
coast, reports Stanford University researcher Page Chamberlain.
A large part of the condor's current diet is dead animals provided by
conservationists, said Chamberlain, a professor of environmental
science.
"We need to find a natural food source," he said, and the marine
mammals could be it.
Condors will eat whatever they can find, he explained, and once they
find a source of food they will continue to fly over the area looking
for more.
To help reintroduce them to the seals and sea lions some young condors
are being raised in pens near the marine mammals breeding ground. When
these are released they know of this source of food and others will
follow them there, Chamberlain said.
Chamberlain's research team has studied what condors were eating over
the last 10,000 years. They determined the diet by comparing the
amounts of carbon and nitrogen in feather and bone fragments over time.
Their findings are reported in Tuesday's issue of Proceedings of the
National Academy of Sciences.
At one time California condors ranged across the nation from the West
Coast across the southern states and even north to western New York.
The researchers found that 10,000 years ago marine mammals were an
important component of condor diets along the West Coast, while the
birds living inland focused on the abundant large mammals. With the
extinction of many large mammals, condor range was reduced to the West
Coast and the food source from the ocean.
Indeed, Lewis and Clark reported seeing the giant condors feeding on
whale carcasses in 1806 in the mouth of the Columbia River.
In the following years the seal and sea lion population was reduced by
trapping, and condors turned to land animals, particularly cattle which
were then being introduced into California.
Over time, however, condor numbers declined with only a few remaining,
mostly in captivity. With efforts underway to re-establish populations
of wild condors the growing availability of marine mammals along the
coast should enhance their chance of surviving.
The research was funded by the Lucille and David Packard Foundation,
the National Science Foundation, U.S. Fish and Wildlife Service and
Bodega Bay Institute.
___
On the Net:
Proceedings of the National Academy of Sciences: http://www.pnas.org
Copyright © 2005 The Associated Press. All rights reserved. The
information contained in the AP News report may not be published,
broadcast, rewritten or redistributed without the prior written
authority of The Associated Press.
Copyright © 2005 Yahoo! Inc. All rights reserved.
Questions or Comments
Privacy Policy -Terms of Service - Copyright/IP Policy - Ad Feedback