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Well, there's a food chain, and the bottom line is that foxes always rule! |
Posted on 12/01/2003 10:57:28 AM PST by CedarDave
Saturday, November 29, 2003
NMSU Biologist Wants Island's Eagles Evicted To Save Foxes
By John Fleck
Journal Staff Writer
What can humans do when the needs of two threatened species clash?
In the case of eagles and foxes on California's Santa Cruz Island, one of the species has to go, according to a New Mexico State University biologist.
Golden eagles eat foxes, and even a few of the eagles pose a serious threat to the fox species, which is teetering on the brink of extinction, according to NMSU wildlife biologist Gary Roemer.
Island foxes are an endangered species, with all the protections under federal law that implies. But golden eagles also are protected by federal law.
In research published Friday, in the journal Science, Roemer and his colleagues conclude that the only way to save the foxes is to get rid of the noble but deadly golden eagle.
"It doesn't take very many to have a really large impact on the fox population," Roemer said.
The paper by Roemer and his colleagues— Franck Courchamp of the Université Paris-Sud in France and Rosie Woodroffe of the University of California, Davis— is the latest attempt to sort out a tangled mess in the islands' ecosystems.
The problem on Santa Cruz and the other Channel Islands lies at the convergence of two changes in the island ecosystem, both caused by humans.
The first big change came in the 19th century, when sailors shipping up and down the California coast turned pigs loose on the islands. The pigs multiplied and became a ready source of food for the sailors.
Then in the 1990s, golden eagles pushed from mainland habitat by urban growth began taking up residence on the islands.
The islands had long been bald eagle territory, and the highly territorial bald eagles had kept golden eagles from colonizing the islands. But the bald eagle populations were devastated in the 1960s by the pesticide DDT, creating an opening. With the bald eagles out of the way, the golden eagles were drawn by the same thing as the sailors— tasty pigs.
But once the golden eagles got there, according to research by Roemer and his colleagues, they also began eating little island foxes.
With no previous predators— the bald eagles primarily ate fish, not mammals— the island foxes had been getting a free ride on the island ecosystem. The arrival of the golden eagles changed that.
In 1994 Roemer, then a University of California graduate student, began finding dDBD::mysql::st execute failed: You have an error in your SQL syntax near 's Eagles Evicted To Save Foxes', '115548nm11-29-03.htm')' at line 1 at /export/home/journal/cgi-bin/print_it.pl line 184. ead foxes on the island, and through biological detective work he was eventually able to link the predation to the golden eagles.
In a decade, the island fox population on Santa Cruz Island dropped from 1,500 to fewer than 100.
In an attempt to restore the island ecosystem, the National Park Service plans to eradicate the feral pigs. That should help restore the island's natural vegetation, which has been devastated by the pigs, according Roemer and his colleagues.
But the scientists concluded that it would likely seal the foxes' fate. As pig populations decline, hungry eagles would likely eat more foxes, the researchers conclude.
The only way around the problem is to remove the eagles at the same time, Roemer said. And the only way to do that, he said, would likely be to kill at least some of the golden eagles. Attempts to trap and remove the eagles have only been partially successful, he said.
With the golden eagles' primary food source— the pigs— gone, the goldens would be less likely to return, the scientists believe. In addition, an effort to reintroduce bald eagles on the island should further work to keep the golden eagles at bay, Roemer said.
But for that to work, the researchers believe, every last golden eagle must go.
That, the researchers wrote in Science, is the heart of the dilemma faced by resource managers on Santa Cruz— saving the fox requires removal "by any and all means" of the federally protected birds.
Copyright 2003 Albuquerque Journal
What to do if an endangered owl eats endangered salamanders or mice?
Answer: change the subject and write another grant request.
What I see here is a failure of imagination. What you do is to import a whole bunch of poodles. They won't bother the foxes and the eagles will find them tasty.
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Well, there's a food chain, and the bottom line is that foxes always rule! |
Let me know if you wish to be added or removed from this list.
I don't get offended if you want to be removed.
That's something like,
'BLM Wants People To Re-locate So Forests Can Burn'
And humans are at bottom of the list.
Duh! That was so obvious, I was just about to post this point, until I read further and saw it. Why don't they just let go and let the different species work it out according to Darwin, whom they worship.
Fire the biologists and let the winner take all.
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