CBI worked with San Diego Management and Monitoring Program (SDMMP) and San Diego land managers to conduct a comprehensive review of existing information for San Diego thornmint, Acanthomintha ilicifolia.
Under a Local Assistance Grant from the California Department of Fish and Wildlife, the Conservation Biology Institute worked with the San Diego Management and Monitoring Program (SDMMP) and land managers in the San Diego region to conduct a comprehensive review of existing information, past and current research, and current management and monitoring efforts for San Diego thornmint, Acanthomintha ilicifolia. SDMMP assimilated a spatially explicit database of all populations and conducted habitat suitability modeling for this species.
This report addresses the management challenge that we face with many annual, edaphic species that undergo large population fluctuations, occur across a fragmented landscape, are vulnerable to many threats and stressors, and may have low genetic diversity due to reduced population sizes, geographic isolation, and loss of pollinators. Therefore, our approach may serve as a model for other plant species covered by the Natural Community Conservation Planning programs in San Diego County. This approach included:
- Obtaining all existing data and interviewing land managers and thornmint experts.
- Developing a conceptual model that articulates our assumptions about natural drivers, stressors, and threats and identifies critical uncertainties.
- Modeling habitat suitability for San Diego thornmint, as well as the nonnative invasive grass species Brachypodium distachyon, and identifying vegetation and soil correlates and landscape context.
- Modeling climate influences and evaluating potential impacts of climate change.
- Hypothesizing a regional population structure and identifying potential habitat connectivity.
- Prioritizing opportunities for enhancement or connectivity.
- Prioritizing management actions, Best Management Practices.
Appendix A of this document provides the necessary information for inclusion in the Management Strategic Plan prepared by the SDMMP. Appendix B provides a comprehensive matrix of populations with data contributed by land managers. Appendix C includes a conceptual model and threats assessment and provides the results of SDMMP habitat suitability modeling. Appendices D and E provide Best Management Practices and monitoring metrics, respectively.