Arroyo toad remains classified as endangered

December 23, 2015 by Ashley Spratt, U.S. Fish and Wildlife Service
This small, buff colored toad has a soft, high whistled trill that is often mistaken for the call of an insect. It was listed as endangered in 1994. Credit: USFWS

The U.S. Fish and Wildlife Service (Service) is withdrawing a proposed rule to reclassify the arroyo toad from endangered to threatened under the Endangered Species Act. New information gathered through a scientific, peer-review process shows that populations have not stabilized, have declined in some areas, and that the toad still faces the threat of extinction.

In 1994, the Service designated the arroyo toad as an endangered species under the ESA due to a combination of man-made and natural threats to the species' survival. While ongoing conservation efforts by state and federal stakeholders have reduced some of the threats to the arroyo toad, the species' overall population has not yet responded enough to prevent the possibility of extinction.

"This announcement underscores that the Service is committed to using the best available scientific information to inform our decisions," said Steve Henry, field supervisor of the Service's Ventura Fish and Wildlife Office. "We look forward to continuing to work closely with our federal, state and local partners to fully recover the arroyo toad."

Factors contributing to the toad's decline include urban development, agricultural conversion, mining and prospecting activities, operation of dams and changes in water flow, alteration of the natural fire regime, and road development and maintenance. Additionally, the introduction of non-native predator species, like the bullfrog, and limited water resources due to drought, led the species to be at risk of extinction.

While some of these threats have been alleviated, recent data suggest arroyo toad populations have not stabilized and are declining in both the southern and northern portions of the species' current range. These declines are apparent in the following basins of the species' current known southern range: the Lower Santa Margarita River Basin, Upper San Luis Rey River Basin, Upper and Lower Santa Ysabel Creek Basins, Upper San Diego River Basin, Upper Sweetwater River Basin, and Upper and Lower Cottonwood Creek Basins. In the northern portions of the species' range, including the Salinas River Basin, Santa Ynez River Basin and Santa Clara River Basin, recent data suggest similar population declines. No long-term data are available pointing to population increases at other locations where the arroyo toad is known to exist.

Through Section 7 of the Endangered Species Act, the Service works with federal agencies to decrease or mitigate impacts of urban development and road construction in arroyo toad habitat. Water releases from some dams have also been altered to more closely mimic the natural flows that support arroyo toads.

Management actions taken by the U.S. Forest Service include cattle exclusions, road crossing improvements and monitoring, and changes to projects to avoid impacting important arroyo toad breeding habitat. Similarly, the Department of Defense has conserved arroyo toad populations on military lands through its Integrated Natural Resource Management Plans.

Additionally, the implementation of Habitat Conservation Plans in southern California have placed portions of three additional river basins that support arroyo toads in reserves providing permanent protection for the species from development in those areas.

The service will continue to work alongside federal, state, local and non-profit partners to support monitoring and surveying work for the arroyo toad and conservation and management efforts for the .

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