Two Texas natives struggle to surviveStudy stresses an urgency to help whooping cranes and Houston toads
Dec. 13, 2005
By DINA CAPPIELLO
Two of the world's most endangered species call Texas home, and unless action is taken now to protect their habitat, they likely will become extinct, according to research published today in the Proceedings of the National Academy of Sciences.
The whooping crane and the Houston toad are among 27 creatures in the United States and 794 worldwide listed in the study, which for the first time constructs a global map of species that not only are endangered, but also reside in only one place on Earth.
The researchers argue that these sites should be targeted for immediate action to prevent species loss, otherwise the planet would lose three times as many species as it did in the last 500 years.
Texas has 91 endangered or threatened animal and plant species, according to the the U.S. Fish and Wildlife Service. Only the whooping crane and Houston toad, however, with their sharply limited habitats, were included in the research published today.
"We now know where the emergencies are: the species that will be tomorrow's dodos unless we act quickly," said Taylor Ricketts, a scientist with the World Wildlife Fund, and one of the authors of the study.
Aransas National Wildlife Refuge, the winter home of the last 216 wild whooping cranes in the world, and Bastrop County, which has the largest remaining population of the Houston toad, are among 595 sites worldwide that if safeguarded could save hundreds of species, the research concludes. Mexico, Colombia and Brazil have the most sites housing the only populations of one or more species. Eighteen of the sites are in the United States.
"We want to create a frontline defense against species extinctions," said Mike Parr, secretary for the Alliance for Zero Extinction, a consortium of 56 groups from 18 different countries.
"If we lose these sites, it will be a cost to biodiversity," Parr said. "We don't have a global mechanism to deal with these species."
A shift in species' trends
The two Texas species represent the changing face of extinction, although both have been listed as endangered in this country since 1970.
Historically, birds accounted for the majority of extinctions. In the last 500 years, however, amphibians like the Houston toad have made up more than half of all endangered species. The research included mammals, birds, reptiles, amphibians and conifers.
The paper also points to a shift in where species are on the verge of extinction. While 80 percent of the 245 species that have perished in the last 500 years lived on isolated islands, many of those recognized in the paper, including the Houston toad and whooping crane, are located on continents near densely populated areas. Nearly half — 43 percent — of these sites have no legal protection.
Even the Aransas refuge, with 22,500-acres protected, is being hemmed in by development, according to Tom Stehn, the national whooping crane coordinator for the U.S. Fish and Wildlife Service. Two subdivisions are planned for areas near where whooping cranes are known to return. The Gulf Intracoastal Waterway runs through the area. And the demand for freshwater from development upstream on the Guadalupe River has Stehn concerned about whether the refuge's marshes will be able to continue to support the flock.
"People are watching out for this species, so it is not going to disappear overnight," he said. "But it's one of those species you have to really keep an eye on ... because it is so concentrated."No protection for toad
The home of the Houston toad is on the leading edge of Austin's sprawl. One fifth of Bastrop County — 124,000 acres — is classified as toad habitat. But only 500 acres are protected for toad conservation, according to Mike Forstner, a Texas State University professor who is studying the toad, which breeds solely in the loose sands of the Lost Pines area.
"With the Houston toad, the onus and the glory in its protection is going to rest not on governmental agencies, but on individual landowners and individual organizations," Forstner said. But "if it doesn't happen now, I'm afraid it is not going to happen."
The U.S. House of Representatives recently approved legislation to reform the Endangered Species Act, the sentinel law protecting this country's rare plants and animals. Reform supporters say the changes will provide incentives for private landowners to conserve habitat by speeding approvals and compensating owners when plans for their property are derailed because of an endangered species.
"To date, the unintended consequences of the law have resulted in real disincentives for private property owners to willingly engage in species recovery efforts," said Brian Kennedy, a spokesman for the House Resources Committee. The committee's chairman, Rep. Richard Pombo, R-Calif., sponsored the reform bill, which passed in late September.
"If you take a look at the recovery rates that the Endangered Species Act has posted in the last three decades, they are abysmal," Kennedy added. "Then, take a look at the fact that 90 percent of endangered species have habitat on private land."
But some parts of the law that would be voided by the pending legislation, including the designation of critical habitat to protect species, could spell trouble for exactly the kind of species the study highlights — those that are picky about where they live.
"This is the only spot they come to, so it is obvious where critical habitat should be," Stehn said.
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