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INFO/LITERATUUR/BOEKEN/ARTIKELS => TURTLENEWS => Topic gestart door: schildpaddennetcrew op 3 Oktober 2008, 16:52:40



Titel: O.C. turtles crowded out - A biologist does her best to remove intruders...
Bericht door: schildpaddennetcrew op 3 Oktober 2008, 16:52:40
ORANGE COUNTY REGISTER (Santa Ana, California) 14 July 06 O.C. turtles crowded out - A biologist does her best to remove intruders, mostly discarded pets. (Pat Brennan)
Fullerton: The scattering of hungry little heads waited expectantly on the pond's surface as biologist Sara Schuster cast her line into the water.
Two turtles fought and tussled as she reeled in the bait, both of them following it to the water's edge. Then Schuster's accomplice, Sharon Paquette of the California Turtle & Tortoise Club, sprang the big surprise: She drew her submerged net upward, scooping up the moss-covered reptiles.
It was Day 4 of the great turtle roundup. Total caught: 176.
"It's just too easy," Schuster said.
Schuster, with the U.S. Geological Survey, is under contract to clear two ponds at the Fullerton Arboretum of a variety of nonnative turtles. She uses fishing line and bait, but no hooks.
"Actually, we're using stew beef," she said as she prepared to make her next cast. "We tried bacon, but the bacon falls apart too easily."
Paquette's job will be finding the turtles new homes. Only people with ponds need apply.
The turtles, dumped into the ponds by pet owners who no longer want them, devour the arboretum's water plants – especially the spectacular Victoria amazonica, a lily pad that can grow to six feet in width.
"We started with pads over two and a half feet across," said Glen Williams, the arboretum's garden manager. "Within a week, they were gone."
The turtles are quickly caught because they are so abundant, and because they are fearless, aggressively pursuing any food that's tossed in by visitors – Cheerios, Froot Loops, Cheetos, bread.
"The kids feed them chips," Schuster said. "They just come up with the ducks. These guys just don't have a fear of people – till we come and completely destroy their world."
And that leads Schuster to mention the bigger problem: competition with California's lonely native, the western pond turtle.
The nonnatives, including red-eared sliders, yellow-bellied sliders, map turtles and soft-shelled turtles, come from the eastern and southern United States, where competition among turtles is fierce.
Evolution has honed them into competitive bullies. The western pond turtles, however, evolved without competition; they are shy, retiring and easily overwhelmed by the nonnatives, which out-compete them for food and nesting territory.
After four days of trapping multitudes of turtles, only a single western pond turtle was found. It was measured and weighed and a tissue sample taken for genetic analysis, then released, Schuster said.
The problem is that the nonnatives are popular among aquarium hobbyists – at least until they get too big.
"They stink," Schuster said. "They're too much work. And they get pretty large. People decide they don't want to deal with them anymore."
So disenchanted pet owners flock to almost any pond that can be found in Orange County to surreptitiously unload their aquarium turtles. Western pond turtles have grown scarce as a result – in fact, in some of their former haunts they are nonexistent, completely replaced by nonnatives.
Schuster expects to wrap up her trapping today. But she knows that won't be the end of the story.
"People will keep dropping off the nonnatives," she said. "They'll be back. They'll have lots of babies."

http://www.ocregister.com/ocregister/homepage/abox/article_1211768.php