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The U.S. Geological Survey (USGS) began work on SANDAG TransNet Environmental Mitigation Program Land Management Grant Agreement 5001140 to conduct southwestern pond turtle restoration and invasives removal at Sycuan Peak Ecological Reserve (SPER). The USGS in conjunction with the San Diego Zoo and the California Department of Fish and Game (CDFG) have continued work begun on the southwestern pond turtle by USGS in 2002 in efforts to enhance and restore the population at the SPER. This is the largest population within the MSCP but had no detectable recruitment in recent (2002-2003) surveys (MaddenSmith et al. 2005). Southwestern pond turtles (and other native aquatic species) are heavily impacted by nonnative species in the riparian habitat which include bullfrogs, largemouth bass, sunfish, crayfish and nonnative turtles. Much like nonnative plants, these aquatic nonnatives can spread throughout the riparian areas and directly impact the natives through predation and also indirectly through competition (Holland 1991; Brattstrom & Messer 1988). Similar to revegetation efforts, successful pond turtle restoration efforts include removal of nonnatives and headstarting of the native turtles (Spinks et al. 2003).

The Pacific pond turtle (Actinemys marmorata) is the only native aquatic turtle species in southwestern California. While historically abundant in most major San Diego County drainages: habitat loss, human disturbance, hydrologic alterations, and invasive species have resulted in a significant decrease in Pacific pond turtle populations in San Diego and throughout California (Madden-Smith et al. 2005). Evaluating and addressing these threats is critical for the long-term persistence of Pacific pond turtle populations in San Diego County, and is a focus of the Multiple Species Conservation Program (MSCP), an approved Natural Community Conservation Plan (NCCP) in southern San Diego County. The Pacific pond turtle is a MSCP covered species with an impact avoidance condition. The condition is as follows: "Maintain and manage areas within 1500 feet around known locations within preserve lands for the species. Within this impact avoidance area, human impacts will be minimized, non-native species detrimental to pond turtles will be controlled, and habitat restoration/enhancement measures will be implemented." During a 2002-2003 study conducted by the United States Geological Survey (USGS), 72 sites within the MSCP area were surveyed for Pacific pond turtle presence. Pacific pond turtles were detected at only 5 of these 72 sites (Lake Murray, Los Penasquitos Canyon Preserve, Lusardi Creek Preserve Lands, Santee Lakes, and Sycuan Peak Ecological Reserve), only 3 of which had more than one individual (Los Penasquitos Canyon Preserve, Lusardi Creek Preserve Lands, and Sycuan Peak Ecological Reserve along the Sweetwater River; Madden-Smith et al. 2005). The surveys conducted by the USGS in 2002-2003, provided valuable information regarding the distribution of Pacific pond turtles, and raised management concerns about their viability. Following the 2002-2003 survey efforts, MSCP managers have sought to assess additional unsurveyed sites, and to prioritize and implement restoration actions to ensure the persistence of western pond turtles within the MSCP Preserve System. The Boulder Oaks Preserve became a part of the MSCP preserve system in 2003 after completion of the 2002-2003 USGS survey and has not been surveyed for Pacific pond turtles. Boulder Oaks Preserve includes three ponds which are potential habitat for Pacific pond turtles. Unlike other sites where restoration actions may be affected by human impacts (e.g., invasive species i