It's Official: Arroyo Seco Creek Designated Critical Habitat for the Arroyo Toad


February 7, 2001 -- The US Fish and Wildlife Service today issued its final order designating 182,000 acres of Central and Southern California streams as critical habitat for the endangered Arroyo Toad.   Six miles of the Arroyo Seco Stream ranging from the top of Devil's Gate Reservoir into the San Gabriel Mountains are included in the designation that will take effect on March 9, 2001. The designation could affect watershed planning efforts and the development of Hahamongna Watershed Park.

The official designation states: "Critical habitat identifies specific areas that are essential to the conservation of a listed species and may require special management considerations or protection. The primary elements for the arroyo toad are those habitat components that are essential for the primary biological needs of foraging, breeding, growth of larvae (tadpoles) and juveniles, intra-specific communication, dispersal, migration, genetic exchange, and sheltering. All areas designated as critical habitat for the arroyo toad contain one or more of the primary constituent elements."

The Fish and Wildlife Service document details a recovery strategy for the endangered toad:

"The recovery strategy for the arroyo toad focuses on providing sufficient breeding and upland habitat to maintain self-sustaining populations and metapopulations of arroyo toads across the historic range of the species in California. To recover the arroyo toad to the point where it can be downlisted or delisted, it is essential to preserve the speciesí genetic diversity as well as the variety of ecological environments in which it has persisted.

"We are designating critical habitat on lands that are considered essential to the conservation of the arroyo toad. Using the recovery plan for guidance, we determined an area was essential if it had one or more of the following characteristics: (1) supports a substantial core population of arroyo toads; (2) supports at least a small toad population and possesses favorable habitat conditions for population expansion and persistence; (3) suitable habitat situated in a location that appears to be crucial for maintaining the viability of a larger metapopulation; (4) occupied habitat on the periphery of the arroyo toadís geographic range; and (5) occupied habitat in atypical or underrepresented ecological environments (e.g., high elevation or desert-edge populations). These areas have the primary constituent elements described above."

The local listing affects the entire Arroyo stream north of Devil's Gate Reservoir to the conjunction with Long Canyon six miles north in the San Gabriel Mountains.  The area is listed as part of the Upper Los Angeles River Basin.  The report states:

"Unit 7 includes portions of Big Tujunga, Mill, Alder, and Arroyo Seco creeks, and adjacent uplands. The unit encompasses approximately 3,225 ha (7,970 ac), of which 62 percent is within the Angeles National Forest and 38 percent is private land. Subunit 7a includes 19 km (11.8 mi) of Big Tujunga Creek from below Big Tujunga Dam downstream to Hansen Lake. Subunit 7b encompasses: (1) approximately 13 km (8 mi) of upper Big Tujunga Creek from immediately above Big Tujunga Reservoir upstream to 2 km (1.2 mi) above the confluence with Alder Creek, (2) almost 6 km (3.7 mi) of Mill Creek from the Monte Cristo Creek confluence downstream to Big Tujunga Creek, and (3) 3 km (1.9 mi) of Alder Creek from the Mule Fork confluence downstream to Big Tujunga Creek. Subunit 7c includes 9.5 km (6 mi) Arroyo Seco Creek from the Long Canyon confluence downstream to the upper end of Devilís Gate Reservoir.

"Arroyo toads have recently been documented (in the last 5 years) in each of these drainages and, collectively, they represent the only significant known population remaining in the coastal foothills of the San Gabriel Mountains. This unit is essential primarily because it is occupied and contains favorable habitat conditions for major population increases, particularly if the timing of water releases from Big Tujunga Dam can be adjusted to restore the seasonal habitat conditions necessary for successful arroyo toad breeding. In addition, populations in Alder, Mill, and Arroyo Seco creeks extend into high-elevation environments that are atypical for the arroyo toad and may be important to maintaining genetic diversity."


Read the official designation (pdf)                 Recent News Coverage