Wily alligators use twigs as lures to feed on birds
Those big, beady, reptilian eyes glaring up from the water surface? They're not just looking at you. They're thinking it over.
Everyone who works with alligators, it seems, has a tale to tell about their smarts:
About a dozen alligators at St. Augustine Alligator Farm Zoological Park in Florida have learned their names and come when they're called, said zoo director John Brueggen, one of the authors of the recent "twig" study of crocodiles.
One former zoo crocodile apparently did not like fish, Brueggen said. So when fed a fish, the crocodile would take it to a pond bank, wait for a vulture to descend, then eat the vulture.
Lowcountry gators have learned that fish die in oxygen-depleted water, and gather very quickly when oxygen levels begin to drop, said wildlife biologist Phil Wilkinson.
S.C. wildlife biologists tell a now classic tale about gators' homing instinct. A 6-foot gator trapped in a pond near Beaufort was released on an island in Bulls Bay more than 30 miles and five river basins away. It was caught again in its home pond 14 years later - as a 10-footer.
American alligators, and their cousin Indian marsh crocodiles, apparently have figured out that if they balance twigs on their snouts, wading birds will try to snatch them for nests. For the quick-snapping gator, that's free lunch.
In other words, the beast with a brain the size of a bean knows how to use it. That could make a person think twice about trying to outwit a "dumb" gator in Lowcountry waters.
A recently released study - published in Ethology, Ecology and Evolution - is the first to document "lure-baiting" by the species, and one of the few lure-baiting behaviors documented among animals overall.
Nah, you say - just dumb luck? Well, the study documented that alligators in Louisiana use the twig trick only during a relatively brief bird nesting season.
They have thought this thing through.
"For people working with alligators it comes as little surprise because we already know how smart they can be. But for the general public it is apparently a bit unexpected," said Vladimir Dinets, a University of Tennessee psychology researcher, who is the study's lead author.
"They are capable of very unique things when it comes to feeding," said wildlife biologist Phil Wilkinson of Georgetown, who has spent more than 30 years studying the American alligator.
Wilkinson has never seen anything like the twig trick, he said, but alligators do lie in wait below tree-nest hatches in case one of the chicks falls in.
"They seem to have a unique way of finding things like that, much better than the bird (species)."
Ron Russell, of the Lowcountry's Gator Getter Consultants, who manages the reptiles' populations for Lowcountry subdivisions with large water tracts, chuckled when he heard of the finding.
Their knowledge has accumulated over 260 million years, he said of the ancient species. "If you look at it that way, common sense will tell you that if it's feasible and they can think about it, they will try to adapt to it," Russell said.
After all, it only took a generation or so of development to teach young alligators that suburban housing ponds are safer than nearby rivers from predators such as larger alligators, he said.
"They're pre-built wintering holes."
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