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Survey Results for the Arroyo Toad (Bufo californicus) in the San Bernardino National Forest, 2001 Final Report Arroyo Toad Metamorph, Little Horsethief Canyon Prepared for: U.S. Department of Agriculture U.S. Forest Service Steve Loe U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY WESTERN ECOLOGICAL RESEARCH CENTER Survey results for the Arroyo Toad (Bufo californicus) in the San Bernardino National Forest, 2001 By Chris Brown1 and Robert Fisher1 U.S. GEOLOGICAL SURVEY WESTERN ECOLOGICAL RESEARCH CENTER Final Report Prepared for: U.S. Department of Agriculture U.S. Forest Service Steve Loe 1San Diego Field Station USGS Western Ecological Research Center 5745 Kearny Villa Road, Suite M San Diego, CA 92123 Sacramento, California [2002] U.S. DEPARTMENT OF THE INTERIOR GALE A. NORTON, SECRETARY U.S. GEOLOGICAL SURVEY Charles G. Groat, Director The use of firm, trade, or brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. For additional information, contact: Center Director Western Ecological Research Center U.S. Geological Survey 7801 Folsom Blvd., Suite 101 Sacramento, CA 95826 CONTENTS Introduction 5 Methods 5 Results and Discussion 6 Summary 19 Literature Cited 21 Tables Table 1—Summary of Sites 22 Table 2—Site Coordinates 23 Table 3—Arroyo Toad Observations 24 Figures Fig. 1—San Bernardino NF Study Sites 25 Fig. 2a—Bautista Canyon 26 Fig. 2b—Bautista Canyon 27 Fig. 3a—Cajon Wash and Lone Pine Valley 28 Fig. 3b—Lone Pine Valley and Cajon Wash 29 Fig. 3c—Cajon Wash below Blue Cut 29 Fig. 4a—Cucamonga Creek 30 Fig. 4b—Cucamonga Creek 31 Fig. 5a—Deep Creek 32 Fig. 5b—Deep Creek Pool 32 Fig. 6a—Grass Valley 33 Fig. 6b—Arroyo Toad from Grass Valley 33 Fig. 6c—Grass Valley Pool 34 Fig. 7a—Little Horsethief Canyon 35 Fig. 7b—Little Horsethief Canyon 36 Fig. 8—Lytle Creek 37 Fig. 9a—Mojave Forks Dam 38 Fig. 9b—Mojave Forks Dam 38 Fig. 9c—Mojave Forks Dam 39 Fig. 9d—Deep Creek above Mojave Forks Dam 39 Fig. 10a—San Gorgonio River 40 Fig. 10b—San Gorgonio Wash 41 Fig. 11—San Jacinto River 42 Fig. 12a—Whitewater Canyon 43 Fig. 12b—Whitewater Canyon North Fork 44 Fig. 13—Summit Valley 45 Photos of Observed Species Toads 46 Frogs 47 Salamanders 48 Lizards 49 Snakes 51 INTRODUCTION The arroyo toad (Bufo californicus) had historic populations throughout many of the river and river wash systems in Southern California (U.S. Fish and Wildlife Service, 1999; Jennings and Hayes, 1994; Cunningham, 1961). For breeding, this species has specific habitat requirements consisting of sandy low gradient open wash habitat with slow moving or pooling water. Historically, these sandy washes were abundant in the foothills and lowland regions of Southern California. Urban development and riparian modification (water diversion, impoundment, channelization) have destroyed much of this habitat. Because of this habitat loss and due to its decline throughout much of its original range this species was designated a Federal Endangered Species in 1994 (U.S. Fish and Wildlife Service, 1999). In the San Bernardino National Forest, the US Forest Service and various contractors have monitored the arroyo toad for several years (Beaman et al, 1995; Brown et al, 2001). In 2000, the US Geological Survey in conjunction with the USFS began monitoring several known populations of the arroyo toad and examined other stream systems for suitable habitat and for presence of the arroyo toad at these new study sites. These surveys continued in 2001 at many of the same study sites as well as some previously unexamined reaches of stream. Summaries of the 2001 surveys are presented in tables 1 and 2 (including survey dates, coordinates, species observations and notes). Arroyo toad observations are summarized in table 3, including demographics and coordinates of the individuals. Figure 1 contains a regional map of the general locations of the survey reaches. Detailed maps of individual survey reaches and site photos are included as figures 2a through 12b. METHODS Each stream or river system was examined to determine the reach of suitable habitat for the arroyo toad, including both riparian and upland features 5 prior to conducting surveys for arroyo toads. Habitat suitability surveys were conducted in accordance with US Fish and Wildlife standards at each study site (U.S. Fish and Wildlife Service, 1999). Representative photos of each study site were taken. Nighttime surveys were conducted for arroyo toads following USFS and USFWS protocols (U.S. Fish and Wildlife Service, 1999b). The presence of other vertebrates observed within the survey reach was also recorded. Arroyo toad locations and start and end points were recorded by GPS for each survey reach. Points of interest, including possible breeding pools, beaver dams, stream obstructions or other unique features, were recorded by GPS and photographed for seasonal and annual comparisons. Because of the remote and unknown nature of some of the study sites, relatively more effort was expended investigating the reaches for suitable habitat (including Whitewater and San Jacinto River). The results of these surveys are presented by study site. Representative specimens of arroyo toads and other vertebrate species were photographed. RESULTS AND DISCUSSION Twelve study sites were examined in the San Bernardino National Forest. Arroyo toads were found at five study sites. In total, 42 adult arroyo toads were individually recorded. In addition, at Little Horsethief Canyon (see Fig. 7), several arroyo toads were heard calling and four arroyo toad metamorphs were observed. Larval arroyo toads were observed at two of the study sites (Little Horsethief Canyon and Mojave Forks Dam, see Fig. 7 and 9a). No arroyo toads were heard calling where adults were not visually observed. A summary of the 2001 surveys including survey dates, arroyo toad observations and other species observations is presented in Table 1. Coordinates for the survey sites are included in Table 2. A summary of arroyo toad observations, including coordinates and morphometrics, is included as Table 3. 6 San Bernardino National Forest (see Fig. 1) Within the San Bernardino National Forest, the study sites were spread throughout three mountain ranges: the San Gabriel, San Bernardino and San Jacinto Mountains. Arroyo Toads were observed in the San Bernardino and San Jacinto Mountain Ranges at the following study sites: Bautista Canyon, Deep Creek Hot Springs, Grass Valley, Little Horsethief Canyon and Mojave Forks Dam and incidentally observed in Summit Valley. Descriptions of the study sites including visible disturbances and threats are listed below. Referenced figures include maps of each study site including arroyo toad locations where observed, aerial photographs of study sites and photographs of points of interest. Photos of representative herpetofauna observed at the study sites are included as Appendix A. Bautista Canyon (see Fig. 2a and 2b) Survey Results and Comments The most downstream third of the Bautista Canyon survey site, which begins at the USFS boundary line and heads south (upstream) to Hixon Trail was dry during the 2000 surveys, and was subsequently not surveyed in 2000. In 2001, water persisted for approximately 0.2 miles below Hixon Trail. This area was surveyed and one arroyo toad was observed in this section. The portion of the reach below this has small boulders present in sandy alluvium along with coastal sage scrub interspersed with cottonwoods (Populus spp.) and mulefat (Baccharis spp.) and thus may support arroyo toads in relatively wet years. On the first survey (5/16/01), seven arroyo toads were observed including four individuals that were found on the roadway (Fig. 2a). In addition to these individuals, several western toads (B. boreas), Pacific treefrogs (Hyla regilla), a western spadefoot toad (Spea hammondii) and a banded gecko (Coleonyx variegatus) were observed at the study site. Five arroyo toads were observed on the second visit (5/31/01) within the stream channel, none being observed on the roadway. On 6/1/01, a road riding survey was undertaken to help assess arroyo toad utilization of the reach of highway adjacent to this reach of Bautista Creek, 7 three arroyo toads and one red diamond rattlesnake (Crotalus ruber), were observed on the roadway (Fig. 2a). The third survey (7/10/2001) produced no arroyo toads. Throughout all the surveys, no calling arroyo toads or arroyo toad larvae were observed. Focused surveys should be undertaken to determine location and timing of breeding activities. This reach of Bautista Canyon consists of low gradient sandy streambed with slow moving water suitable for arroyo toads. Visible Disturbances/Threats Amphibian mortality due to traffic may present a problem in Bautista Canyon as Bautista Canyon Road parallels the creek bed and at several locations comes within 50 meters. Incidental to conducting the 2001 surveys, several Arroyo Toads were observed on the nearby roadway while traveling to and from the study site (four of which were observed on the roadway in the vicinity of Bautista Spring). Hixon Trail, which intersects Bautista Creek approximately 1 km south of the forest boundary, supports off highway vehicles and provides easy access for such vehicles to the creek. Although no vehicles were observed on Hixon Trail during these surveys, fresh tire tracks were observed. Cajon Wash and Lone Pine Valley (see Fig. 3a-3c) Survey Results and Comments Even with the disturbances, the habitat in Cajon wash is in very good health. The vegetation is for the most part intact, with minimal incidences of non- native plants. The stream has no sign of invasive species; mosquito fish, sunfish, crayfish, bullfrogs and other common invasive species appear to be absent from the drainage. Pacific treefrogs (Hyla regilla), California treefrogs (H. cadaverina), Western toads (Bufo boreas) and Speckled Dace (Rhinichthys osculus) are abundant throughout the wash.

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