True Blue Texan NeededAug 4th, 2002 | By admin | Category: Blues in the International Press
Iguana species relying on a true blue Texan
By Alison Gregor
Express-News Rio Grande Bureau
Web Posted: 08/04/2002 12:00AM
BROWNSVILLE His name is Godzilla, and he resides at the Gladys Porter Zoo. But his awe-inspiring name may not be enough to save an iguana species on the brink of extinction, though biologists are hoping a mate will do the trick.
Formerly a single iguana, Godzilla recently was introduced to another Grand Cayman blue iguana at this zoo on the U.S.-Mexico border, which specializes in endangered species.
The future of other blue iguanas, one of eight species of rock iguanas, may rest in this couple’s reproductive capabilities.
Biologists were shocked to read a June report that only 10-25 Grand Cayman blue iguanas remain in the wild.
“The situation is critical,” said Rick Hudson, program officer for the International Iguana Foundation and conservation biologist at the Fort Worth Zoo. “If something serious isn’t done, they are going to be functionally extinct in five years.”
In 1993, scientists surveyed the blue iguanas on Grand Cayman, the only place the animals live in the wild, thinking there were as many as 200. Finding 10-25 in June, they extrapolated that 100 or fewer exist worldwide, most in zoos.
The problem for these iguanas is that their habitat is being destroyed at a breakneck pace by urban development, while the growing island population has introduced dangerous predators, such as dogs and cats. And the animals in captivity all have been bred from two or so family lines, so there’s not much genetic diversity.
Reproduction in captivity, followed by reintroduction into the wild, may be all that can save the blue iguana.
There are about 30 blue iguanas in U.S. zoos. Scientists believe they need to support about 200 in captivity for the species to survive, which means construction of more outdoor enclosures in hot, sunny climates.
The San Antonio Zoo has several blue iguanas, but they’re perpetually on loan to other zoos because there are no adequate enclosures to house them at the zoo.
“Its whole future is going to depend on captive management, our ability to breed them in captivity and supplement the wild population,” Hudson said.
That’s where Godzilla comes in. At about 65, he is the oldest lizard in captivity, and the only blue iguana taken from the wild in the 1950s and not born in a zoo. Thus, his genes could be very important to the small genetic pool of captive blue iguanas.
“All the blue iguanas in captivity are related,” said Colette Adams, herpetologist for the Gladys Porter Zoo. “Godzilla is the only one that’s not related. He’s the only wild animal capable of spreading new genetic material.
“The problem is, he has never shown much interest in breeding, even when he was surrounded by females.”
Compounding the problem, Godzilla may be sterile.
With his current mate, one might call the giant lizard henpecked. Last week, in his enclosure at the Gladys Porter Zoo, his much smaller female partner, who has no name, repeatedly interrupted his peaceful sunning activity by charging him and darting back into the bushes for cover.
A stationary bright blue Godzilla rolled his eyes, flashing their blood red sclera, and bobbed his head, the iguana form of communication, at this pestering, but didn’t move.
“He is kind of old, and he is kind of slow,” Adams said, as she fed Godzilla and his mate red hibiscus flowers.
For that reason, zookeepers have to hold the female blue iguana in place when Godzilla mates with her. So far, despite the male blue iguana’s dual reproductive organs, their efforts have been unsuccessful.
Still, scientists are optimistic. Godzilla and his mate do not yet have their reproductive cycles in sync, something that can take a few years, Adams said. When that happens, they may have a better chance of producing offspring.
The Gladys Porter Zoo, in a perfect climate for the blue iguanas and with a successful track record of breeding rock iguanas, also has another breeding pair.
And the unique blue color of the iguanas bodes well for a successful recovery effort, Adams said. While the lizards generally have a blue pallor, when excited, they turn shades of brilliant blue ranging from peacock to turquoise.
“Being blue has its advantages,” she said. “The more charismatic the animal is, the more likely to survive.” Hudson agreed.
“This is the most attractive, the sexiest, of all the iguanas,” he said. “It’s a bright blue gorgeous animal. If we can’t save something like this, I think the rest of them are in serious trouble.”