Disappearing Rocky Mountain toad populations are part of a global wave of amphibian extinctions
By Bob Berwyn
SUMMIT COUNTY — New genetic studies have prompted environmental groups to once again seek Endangered Species Act protection for boreal toads. The amphibians were once common throughout the Rockies, but their populations have dwindled as the deadly chytrid fungus sweeps around the world.
The Center for Biological Diversity, Center for Native Ecosystems, and Biodiversity Conservation Alliance last week petitioned the U.S. Fish and Wildlife Service to add the Southern Rockies population of boreal toad to the federal list.
In Colorado, they are designated as an endangered species by the Colorado Division of Wildlife. The state also has launched an ambitious breeding and restoration program, and has been carefully monitoring both natural and reintroduced populations for many years. Read more at the CDOW boreal toad website.
The U.S. Fish and Wildlife Service must determine whether the petition has merit within 90 days and make a final finding on toad protection within a year.
“Boreal toads need protection under the Endangered Species Act to have any shot at survival,” said attorney and biologist Collette Adkins Giese of the Center for Biological Diversity. “By addressing threats like the destruction of wetland habitat we can still save these rare amphibians. But the window of opportunity is closing fast.”
Endangered Species Act protection for the toad will increase federal funding for research to stem the deadly chytrid fungus and help save high-elevation stream and wetland habitat from threats like pollution and poorly managed recreation and livestock grazing.
“The boreal toad is the region’s only high elevation, forest-dwelling toad,” said Megan Mueller, a conservation biologist with the Center for Native Ecosystems. “This unique toad is an indicator of the environmental health of our mountain streams and wetlands. The protections of the Endangered Species Act are needed to help safeguard the boreal toad from slipping over the brink of extinction.”
Mueller said the Southern Rockies population is clearly isolated from other populations. Giving the toads endangered status could help protect populations that have shown some resistance to the chytrid fungus, ensuring that they don’t get wiped out from some other impact.
“In Utah, chytrid is not as widespread, it’s a little bit less pervasive. if the toads can get in places where they can get totally dried out, they can get rid of the fungus,” she said. “But the threats to habitat are much more widespread she added, specifying poorly managed livestock grazing, destruction of riparian areas and impacts from recreation and roads as threats. In some cases, off-road vehicle use may be resulting in direct mortality of toads, she said.
“Given the threats that the boreal toad is facing from chytrid fungus and habitat degradation, Endangered Species protection would give this rare animal its best shot at survival,” said Erik Molvar, wildlife biologist with Biodiversity Conservation Alliance. “Streamsides and wetlands are among the most biologically important habitats on our forests, and strengthening protections for boreal toads will have far-reaching benefits for a vast array of forest wildlife, from songbirds to cutthroat trout.”
Background (provided by the Center for Native Ecosystems)
In response to a petition filed by the Biodiversity Legal Foundation (later incorporated into the Center for Biological Diversity), the Service determined in 1995 that boreal toads in the southern Rockies deserved protection under the Endangered Species Act but that higher priority actions precluded listing. The agency added the southern Rocky Mountain population to its candidate list, which currently includes more than 250 species, most of which have been waiting decades for protection.
But the toads were taken off the candidate list 10 years later, when the agency said that boreal toads in the southern Rockies were not “significant” in part because they appeared genetically similar to other populations found elsewhere in the West.
Since then, two genetic studies have proven that boreal toads in the southern Rockies are part of an evolutionarily significant “clade” that includes boreal toads in Utah, northeastern Nevada and southern Idaho.
This group of boreal toads contains as much genetic diversity as previously recognized species. Today’s petition seeks federal protection for these genetically unique boreal toads that are experiencing significant declines in population size and distribution. Alternatively, the petition asks the Service to provide Endangered Species Act protection for boreal toads in the southern Rocky Mountains only.
Mounting scientific evidence shows that amphibians are among the most imperiled species on Earth. Globally, 1,898 species of amphibians, or 30 percent of the 6,296 evaluated existing amphibian species, were deemed at risk of extinction in the International Union for Conservation of Nature’s 2010 Red List. In the United States, 56 amphibians, or about 20 percent, are at risk of dying out. Ubiquitous toxins, global warming, ozone depletion, introduction of nonnative fish and habitat destruction are key factors leading to their demise.