Because the FWS has held up projects that could potentially disturb habitat for imperiled species, some feared projects such as stream widening and sediment removal in the Arroyo Seco Master Plan could be nixed in favor of the toad.
So far, preliminary findings show the toad if it once lived in the Arroyo Seco does not live there now, according to studies by the city of Pasadena, U.S. Forest Service and Jet Propulsion Laboratory.
But that could mean the toad population is in flux, said Bill Brown, biologist for the Angeles National Forest.
"It depends on the year. If it's a good wet year, there's more breeding and more baby toads," he said. "If it's a dry year, like we've been having, the breeding is impacted."
The toad, known for its distinctive breeding trill, lives in sandy streams with shallow, gravelly pools. It was once found throughout coastal rivers in California, but now lives in only 22 arroyos.
The Arroyo Seco was included in the 182,360 acres in eight counties set aside for the toad.
The last time an arroyo toad was detected in Hahamongna Watershed Park was in 1999, when a biologist with the Angeles National Forest heard multiple male arroyo toads calling from within the basin.
But the city of Pasadena survey found no trace of the toad between March and July in 2001.
The city must now continue surveying the land for two more years before it will know how the critical habitat designation will affect plans for the park, said Kathy Woods, administrator for the city.
If the toad is found, then the city may have to alter its plans. If the toad is not found three years running, then the FWS may re-evaluate the critical habitat designation, she said.
"It's still too early to say if any project will be completely killed," Woods said.
At JPL, which borders Hahamongna Watershed park, the FWS found the property too developed to support the toad, said Peter Robles Jr., environmental health and safety manager for the NASA management office at JPL.
The agency, which hired a biologist to survey the land, discovered several types of toad there, none of them arroyo.
However, JPL may still be forced to consider the endangered species when working on projects with the city of Pasadena in the future, Robles said.
"Endangered species are the overarching requirement it almost supersedes everything else," he said. "Dams have been stopped, roads have been stopped, airports have been stopped. But the toads let you know you have a healthy environment."
-- Lisa Faught can be reached at (626) 578-6300, Ext. 4496, or by e-mail at lisa.faught@sgvn.com.