Species-Specific Conservation Analyses and Conditions For
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Section 4 Engelmann Oak Engelmann Oak Quercus engelmannii USFWS: None CDFG: None MHCP: None Conservation Goals Ensure species persistence within the plan area by conserving major populations, critical locations, and required habitat of Engelmann oak. Conservation Strategy Conserve and manage all major populations and critical locations along with an amount and configuration of suitable habitat to contribute to species recovery (including occupied habitat and adjacent habitat that supports seed dispersal agents). Implement species-specific management actions as necessary to enhance or protect habitat quality. These may include prohibiting adverse activities within preserve areas, developing fire management guidelines, and enhancing declining populations and restoring damaged habitat. Summary of Findings and Conditions for Coverage Findings. [TBD by wildlife agencies in the Biological Opinion after MHCP public review.] Achievement of Conservation Goals. Subject to all MHCP policies and the specific conditions listed herein, the MHCP will adequately conserve this species by conserving about 82% of known locations and assuming 100% conservation of the major and critical population in Escondido. Increased coordination of monitoring and management may improve knowledge of species’ requirements and habitat quality in the study area. Conditions. The following conditions must also be met by the MHCP to adequately conserve this species: (1) All critical locations in Escondido must be substantially conserved in accordance with the critical location policy and managed as part of the preserve system. (2) All conserved populations must be adequately managed to control edge effects. (3)Fire management plans must be implemented for all conserved populations to protect individual plants and habitat from frequent or high-intensity fires. (4) Declining populations must be enhanced, and damaged habitat restored, if determined necessary through monitoring. (5) Impacts to individual trees shall be avoided and minimized to the greatest extent practicable during project design. Background Distribution, Abundance, and Trends. Engelmann oak occurs in Los Angeles, Orange, Riverside, and San Diego counties; on Santa Catalina Island (one tree); and in Baja California, Mexico (Skinner and Pavlik 1994). In San Diego County, the species occurs primarily east of the MHCP study area, from the Santa Margarita Mountains on the Riverside County-San Diego County border southward towards Dulzura, and east to the desert slope. Large populations are found in PUBLIC REVIEW DRAFT MHCP VOL. II 4-163 314552000 Section 4 Engelmann Oak Pala, Lake Wohlford, Twin Flats, Boden Canyon, Clevenger Canyon, Escondido, Valley Center, Ramona, and Featherstone Canyon. Over 90% of the remaining stands of this species are estimated to occur in San Diego County (Pavlik et al. 1991). Within the MHCP study area, small stands and/or individual trees are found in Carlsbad (vicinity of Agua Hedionda), and larger stands occur in Escondido (Lake Wohlford and Daley Ranch).1 Engelmann oak occurs in canyons and on open slopes in foothill and coastal regions, where it is associated with Engelmann oak woodland, chaparral, and grassland. Within the MHCP, two major populations of Engelmann oak have been identified in Escondido: Lake Wohlford and Daley Ranch (see MHCP Database Records Map). Both populations are considered critical locations. Threats and Limiting Factors. The primary threats to this species are development and livestock grazing. Special Considerations. Engelmann oak is a deciduous tree. Seedlings are fire-tolerant, but mature trees are “fire-sensitive” (Pavlik et al. 1991). Engelmann oak is wind-pollinated, and seeds (acorns) are both self- and animal-dispersed. The level of survey effort for this species in the study area is considered relatively high. Conservation Analysis Conservation and Take Levels. The expected level of take of Engelmann oak is relatively low (Table 4-28). The majority of points (82%) falls within the FPA and will be conserved at 100% within hardline areas and at the FPA percentage within softline areas. No conservation is required for this species outside the FPA. Overall, 81% of the major and critical location of this species is proposed to be conserved in the study area. This includes an estimated 71% of the Lake Wohlford population and 90% of the Daley Ranch population. The critical location policy requires substantial conservation of these populations, and final preserve design in these locations should increase conservation of Engelmann oak in critical locations to over 90%. In addition to conserved point localities, an estimated 170 acres (74%) of potentially suitable habitat will be conserved as a result of the existing preserve design and preserve policies (Table 4- 28). Preserve Configuration Issues. The two major populations of Engelmann oak identified in the MHCP study area will be conserved in relatively large blocks of habitat (150 to 500+ acres) that include a mosaic of vegetation. Conserved habitat that supports the Daley Ranch population, in particular, is sufficiently large that it is expected to support appropriate seed dispersal agents and buffer against edge effects. The Lake Wohlford population occurs partially in a softline area, and the final preserve design will need to minimize habitat fragmentation. 1 The Daley Ranch population was referred to as Escondido (Oat Hills, Dixon Lake) in the Standards and Guidelines (Ogden 1998). 314552000 4-164 PUBLIC REVIEW DRAFT MHCP VOL. II Note: This map only indicates recorded locations in the GIS database and may not represent the true distribution of the species. This map is intended for general display purposes only. The information Camp Pendleton on this map should not be used for site specific planning. For more specific location information, refer to the 1" = 4,000' scale species distribution maps. Daley Vista Ranch Oceanside Buena Vista Lagoon San Major Population Aqua Hedionda Marcos and/or Critical Location Lagoon Escondido Other Carlsbad Natural Habitats Generalized Subarea Plan Boundary Batiquitos Lagoon Major Roads Major Streams Lake Hodges San Pasqual Valley Encinitas Engelmann oak MHCP Database Records Feet 0 8,500 17,000 San Elijo Lagoon Kilometers 2.04 4.08 Solana San Diego Beach ASSOCIATION OF GOVERNMENTS Source: MHCP Species San Dieguito April 3, 2001 database, 1999 Lagoon Section 4 Engelmann Oak Table 4-28 SUMMARY OF NET CONSERVATION FOR ENGELMANN OAK Habitat Location Major Critical Acreage Points Populations Locations Other City Conserved1,2 Conserved3 Conserved Conserved Considerations Carlsbad None 1 of 3 None None --- present (33%) identified identified Encinitas None None None None --- present present present present Escondido 151 (73%) 60 of 72 81% 81% --- (83%) Oceanside None None None None --- present present present present San 19 (82%) 1 of 1 None None --- Marcos (100%) identified identified Solana None None None None --- Beach present present present present Vista None None None None --- present present present present MHCP 170 (74%) 62 of 76 81% 81% --- Total4 (82%) 1 Habitat for Engelmann oak is Engelmann oak woodland. 2 Number indicates the acreage of appropriate habitat (i.e., habitat supporting suitable vegetation) that is conserved. Number in parentheses indicates the percentage of appropriate habitat that is conserved. 3 Approximate number of known location points expected to be conserved based on the applicable calculation rules described in Section 2.2. The percentage in parentheses estimates the overall conservation level as a weighted average for all points, where each point is first assigned a conservation level based on location (e.g., inside or outside FPA) and species type (e.g., narrow endemic or wetland obligate). 4 Numbers may not total due to rounding. 314552000 4-166 PUBLIC REVIEW DRAFT MHCP VOL. II Section 4 Engelmann Oak Effects on Population Viability and Species Recovery. Implementation of the MHCP is expected to protect, conserve, and possibly enhance population viability for this species and therefore contribute to species recovery. The MHCP preserve design and avoidance policies conserve the majority of known locations, while MHCP management practices will address threats that have resulted in the decline of this species throughout the study area. The MHCP will increase funding for monitoring and management, which may improve species stability and long-term persistence. Special Considerations. Mature Engelmann oaks may be adversely affected by unnatural fire regimes (e.g., frequent fires, high-intensity fires resulting from fire suppression policies). Effective conservation of this species must include a fire management plan that protects conserved populations from frequent or high-intensity fires. Adequate preserve design for this species must also include sufficient habitat to support seed dispersal agents. Adaptive Management Program In addition to conserving habitat, the MHCP will integrate monitoring and management actions into an adaptive management program for this species. Monitoring results will help refine the management program described below so that management activities can be adjusted to maximize species recovery potential. Management actions for Engelmann oak within the MHCP should coordinate with existing programs to ensure compatibility of monitoring results and prevent duplication of efforts. Monitoring. Initial monitoring efforts should focus on detecting short-term threats to species persistence (e.g., invasion of nonnative