MANAGEMENT INDICATOR SPECIES ACCOUNT for ARROYO TOAD in the SOUTHERN CALIFORNIA PROVINCE

MANAGEMENT INDICATOR SPECIES ACCOUNT for ARROYO TOAD in the SOUTHERN CALIFORNIA PROVINCE

Appendix C - MIS Species Account - S. Province (07/17/11) MANAGEMENT INDICATOR SPECIES ACCOUNT for ARROYO TOAD IN THE SOUTHERN CALIFORNIA PROVINCE SUMMARY In the Land Management Plan for the southern California National Forests (Southern California Province), the arroyo toad was selected as a Management Indicator Species for low-elevation riparian and aquatic ecosystems. Long-term trends in population abundance, stream occupancy, and habitat condition are expected to reflect the effectiveness of management actions in protecting low-elevation riparian and aquatic habitat from disturbance and habitat degradation. Short-term fluctuations in arroyo toad populations may not indicate the effects of management actions, because toad populations are strongly influenced by weather patterns. However, long-term trends in arroyo toad abundance and habitat are expected to reflect whether management activities and strategies have been successful in improving habitat conditions for the toads and other aquatic and riparian-dependent species that are susceptible to high levels of human disturbance. Monitoring will also indicate the effectiveness in achieving recovery objectives for this listed species. The four southern California National Forests may support approximately 36% of the total range-wide population. Of the 22 drainages that support arroyo toads in California, portions of 12 of these are located on National Forests in the S. Province. Threats to arroyo toads include riparian habitat loss/degradation, water diversions and extractions, impacts from roads and trails, developed and dispersed recreation, non-native plants and animals, unauthorized OHV, grazing, mining and prospecting, and recreational collecting of toads, tadpoles and eggs. Monitoring efforts on the four southern California National Forests have not typically been designed to obtain the level of information needed to determine trend. Based on this, it is not possible to make a definitive statement regarding trends in abundance and habitat conditions for the S. Province. However, monitoring efforts have been able to confirm that all sites previously documented as occupied continue to remain occupied. Page 1 – Arroyo Toad Appendix C - MIS Species Account - S. Province (07/17/11) I. INTRODUCTION Arroyo toads once ranged from San Luis Obispo County, California, south to northwestern Baja California (Gergus et al. 1997 for southernmost record; Mahrdt et al. 2003, Mahrdt and Lovich 2004 for occurrences in Baja California Norte). Arroyo toads are now believed to be extirpated in San Luis Obispo County. Populations persist in headwater areas of Figure 1. The range and streams in Santa Barbara, Ventura, Los distribution of arroyo toads Angeles, Riverside, and San Diego (NatureServ website). counties; recent sightings of scattered individuals have been reported from Orange, San Bernardino, and southern Imperial counties (USFWS 1994) (Figure 1). Sweet and Sullivan (2005) estimated that the arroyo toad (Bufo californicus) is currently present in 65% of its historic range and present in lower abundances than described historically. Arroyo toads are protected on Federal lands, and may be increasing from their lowest abundance documented in the early 1990s (Sweet and Sullivan 2005). Their densities still appear to be low, with about 12 adults/ha along second- to fourth-order streams in montane and foothill areas (Sweet 1993) where it is rare to find >5 calling males/100 m of suitable habitat (Sweet 1992, 1993; Ramirez 2000). Sweet and Ramirez surveyed portions of the Los Padres National Forest (LPNF) and Angeles National Forest (ANF). In relatively protected lowland areas, arroyo toads appear to be higher with 10 calling males/100m (D.C. Holland 2001, cited in Sweet and Sullivan, 2005). II. SYSTEMATICS The arroyo toad is one of three members of the southwestern toad complex (Bufo microscaphus) in the family Bufonidae. When listed in 1994, the arroyo toad was considered a subspecies of southwestern toad (B. m. californicus). The arroyo toad is now considered a separate species (B. californicus) based on genetic studies (Gergus 1998 as referenced in U.S. Fish and Wildlife Service 2001). III. MANAGEMENT DIRECTION The arroyo toad was listed as endangered December 16th, 1994 (59 FR 64859). Critical Habitat was originally designated on February 7, 2001 (66 FR 9414); the final revised Critical Habitat was designated on April 13, 2005 (70 FR 19562). Since then, the Critical Habitat has been Page 2 – Arroyo Toad Appendix C - MIS Species Account - S. Province (07/17/11) revised again with current Final Critical Habitat being designated in February 9, 2011 (76 FR 7645). A Recovery Plan for arroyo toad was issued in 1999. Since the arroyo toad is federally-listed as endangered, much of the management direction comes from LMP, project-specific, and programmatic consultations (and associated Biological Opinions) with U.S. Fish and Wildlife Service (USFWS). Each S. Province Forest is at slightly different places in the Formal Consultation process with USFWS for the impacts of ongoing activities to riparian species, including arroyo toad, since the LMP revision in 2005. The ANF and LPNF are currently preparing their Biological Assessments (BA) and have not yet initiated consultation. The SBNF and CNF have completed their BAs and initiated consultation but not yet received a BO. In addition to Endangered Species Act compliance and direction, the LMP provides management direction for endangered species, including arroyo toad, and the management and protection of riparian habitat. Under the LMP, conservation of riparian habitat is a high priority for all Forests within the S. Province. The LMP set a goal to “improve riparian conditions” (USDA Forest Service 2005). According to the LMP, the desired condition for federally-listed species, such as arroyo toad, is that their habitats are conserved and that the species are conserved or moving toward recovery. Additionally, that flow regimes in streams that provide habitat for threatened, endangered, proposed, candidate, and/or sensitive aquatic and riparian-dependent species are sufficient to allow the species to persists and complete all phases of their life cycles (LMP, Part 1, p. 45). The desired condition for riparian condition is that watercourses are functioning properly and support healthy populations of native and desired non-native riparian-dependent species (LMP, Part 1, p. 41). The LMP states that the desired condition for arroyo toad is that habitat functions sustain healthy populations of native and desired non-native fish and game species and that wildlife habitat functions are maintained or improved, including primary feeding areas, winter ranges, breeding areas, birthing areas, rearing areas, migration corridors, and landscape linkages (LMP, Part 1 p.45). The LMP describes the desired condition for watersheds is that they are healthy, dynamic and resilient, and are capable of responding to natural and human-caused disturbances while maintaining the integrity of their biological and physical processes (LMP, Part 1, p. 40). Long- term trends in population abundance, stream occupancy, and habitat condition are expected to reflect the effectiveness of management actions in protecting low-elevation riparian and aquatic habitat from disturbance and habitat degradation. The LMP management objectives for arroyo toad are that there are properly-functioning streams and stable or increasing populations. Page 3 – Arroyo Toad Appendix C - MIS Species Account - S. Province (07/17/11) IV. SELECTION AS A MANAGEMENT INDICATOR SPECIES The arroyo toad was selected as an MIS for low-elevation riparian and aquatic ecosystems. Long-term trends in population abundance, stream occupancy, and habitat condition are expected to reflect the effectiveness of management actions in protecting low-elevation riparian and aquatic habitat from disturbance and habitat degradation. Short-term fluctuations in arroyo toad populations may not indicate the effects of management actions, because toad populations are strongly influenced by weather patterns. However, long-term trends in arroyo toad abundance and habitat are expected to reflect whether management activities and strategies have been successful in improving habitat conditions for the toads and other aquatic and riparian-dependent species that are susceptible to high levels of human disturbance. Monitoring will also indicate the effectiveness in achieving recovery objectives for this listed species. Habitat improvement projects for arroyo toad and the aquatic and riparian habitats they occupy have included riparian habitat restoration, control of non-native species, prescribed burning to protect riparian areas and reduce the effects of wildfire, relocation of roads and recreation facilities, and Burned Area Emergency Rehabilitation and restoration after wildfires. Trends in abundance, distribution, and/or habitat conditions are to be used as measurements for evaluation. The prescribed monitoring method is population abundance and/or habitat condition in selected locations (LMP FEIS, Vol. 1. p. 177, Table 433). V. ECOLOGY V-1. Ecology - Habitat Requirements The arroyo toad is endemic to the coastal plains, mountains, and desert slopes of central and southern California and northwestern Baja California from near sea level to about 8,000 feet (2,400 meters). Within these areas, arroyo toads are found in both perennial and intermittent rivers and streams with shallow, sandy to gravelly pools adjacent to sand or fine gravel

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