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A presentation from the South County Grasslands Best Management Practices Workshop.

A presentation from the South County Grasslands Best Management Practices Workshop.

Symposium to share information and lessons learned on the adaptive management and restoration of grasslands for rare species, including burrowing owl, Stephens’ kangaroo rat, Otay tarplant, and Quino checkerspot butterfly.

Symposium to share information and lessons learned on the adaptive management and restoration of grasslands for rare species, including burrowing owl, Stephens’ kangaroo rat, Otay tarplant, and Quino checkerspot butterfly.

Symposium to share information and lessons learned on the adaptive management and restoration of grasslands for rare species, including burrowing owl, Stephens’ kangaroo rat, Otay tarplant, and Quino checkerspot butterfly

Symposium to share information and lessons learned on the adaptive management and restoration of grasslands for rare species, including burrowing owl, Stephens’ kangaroo rat, Otay tarplant, and Quino checkerspot butterfly.

Symposium to share information and lessons learned on the adaptive management and restoration of grasslands for rare species, including burrowing owl, Stephens’ kangaroo rat, Otay tarplant, and Quino checkerspot butterfly.

A presentation from the South County Grasslands Best Management Practices Workshop.

A presentation from the South County Grasslands Best Management Practices Workshop.

A presentation from the South County Grasslands Best Management Practices Workshop.

A presentation from the South County Grasslands Best Management Practices Workshop.

Detailed habitat assessments were conducted by CBI, TNC, and SDSU within the four designated South County grassland management planning units: Sweetwater Reservoir, Proctor Valley, Rancho Jamul Ecological Reserve, and Sycamore Canyon (Figure 1). All four units were assessed in 2011; additional assessments were conducted in 2012 at Rancho Jamul Ecological Reserve and Sycamore Canyon. The purpose of these assessments was to document existing habitat conditions and determine habitat suitability for the three target species (burrowing owl, Otay tarplant, and Quino checkerspot butterfly), as well as threats, results of past management actions, and potential management and restoration actions. Data from the habitat assessments were used to identify and prioritize species-specific management actions within each of the four planning areas. In addition, these data were used to identify preliminary vegetation associations, as well as potential restoration sites for native grasslands and forblands. Prior to conducting fieldwork, CBI and TNC reviewed soil maps, aerial photographs, and results of previous vegetation mapping, and plant and wildlife surveys in the project areas and vicinity.

The Conservation Biology Institute (CBI), The Nature Conservancy (TNC), LandIQ, and the California Department of Fish and Wildlife (DFW) conducted a 3-year experiment on Rancho Jamul Ecological Reserve (RJER) to assess different control methods for enhancing Otay tarplant (Deinandra conjugens) in recently burned habitat. The Otay tarplant Habitat Experimental Project (project) goals included: (1) determine whether an Otay tarplant soil seed bank exists onsite, (2) assess the response of Otay tarplant to prescribed fire and nonnative plant control methods and (3) enhance Otay tarplant habitat by controlling nonnative seed production and inputs to the soil seed bank.

This first annual report provides background information and summarizes the tasks performed during the first year (June 2011 to August 2012) of the Otay tarplant (Deinandra conjugens) and San Diego thornmint (Acanthomintha ilicifolia) restoration and enhancement program in the Chula Vista Central City Preserve. Three quarterly reports have previously been prepared by RECON. The information from these reports is summarized below for tasks completed between June 13, 2011 and August 31, 2012. This annual report also summarizes the results of the relevé vegetation surveys that were conducted in spring 2012 at the treatment sites, as well as the population estimates for Otay tarplant and San Diego thornmint.

This document summarizes maintenance and monitoring activities from August 2004 to August 2007 for the vernal pool and Otay tarplant (Deinandra conjugens) restoration project at the Sweetwater Reservoir. The mitigation project includes 2.70 acres of vernal pool complex (vernal pools and associated uplands) restoration and enhancement, and 4.36 acres of Otay tarplant restoration and enhancement. Approximately 8,201 ft2 of vernal pool surface area has been restored or enhanced, including 3,929 ft2 of restored vernal pools. All areas restored and enhanced as part of this mitigation effort are becoming established and are progressing toward the Year 5 final success criteria standards.

This third and final annual report provides background information and summarizes the tasks performed during the third year (September 2013 to August 2014) of the Otay tarplant (Deinandra conjugens) and San Diego thornmint (Acanthomintha ilicifolia) restoration and enhancement program in the Chula Vista Central City Preserve. Three quarterly reports have previously been prepared by RECON. The information from these reports is summarized below for tasks completed between September 1, 2013 and August 31, 2014. This final annual report also summarizes the results of the relevé vegetation surveys that were conducted in spring 2014 at the treatment sites, as well as the population estimates for Otay tarplant and San Diego thornmint.

This report documents maintenance and monitoring activities for Year 5 (March 2009 to August 2010) and summarizes restoration activities to date for the vernal pool and Otay tarplant (Deinandra conjugens) restoration project at the Sweetwater Reservoir. The mitigation project includes 2.70 acres of vernal pool complex (vernal pools and associated uplands) restoration and enhancement, and 4.36 acres of Otay tarplant restoration and enhancement. Approximately 8,201 square feet (ft2) of vernal pool surface area has been restored or enhanced, which includes 3,929 ft2 of restored vernal pools. Overall, the vernal pool and Otay tarplant mitigation efforts have been moderately successful; however, all Year 5 final success criteria standards have not yet been achieved.

This second annual report provides background information and summarizes the tasks performed during the second year (September 2012 to August 2013) of the Otay tarplant (Deinandra conjugens) and San Diego thornmint (Acanthomintha ilicifolia) restoration and enhancement program in the Chula Vista Central City Preserve. Three quarterly reports have previously been prepared by RECON. The information from these reports is summarized below for tasks completed between September 1, 2012 and August 31, 2013. This annual report also summarizes the results of the relevé vegetation surveys that were conducted in spring 2013 at the treatment sites, as well as the population estimates for Otay tarplant and San Diego thornmint.

This third and final annual report provides background information and summarizes the tasks performed during the third year (September 2013 to August 2014) of the Otay tarplant (Deinandra conjugens) and San Diego thornmint (Acanthomintha ilicifolia) restoration and enhancement program in the Chula Vista Central City Preserve. Three quarterly reports have previously been prepared by RECON. The information from these reports is summarized below for tasks completed between September 1, 2013 and August 31, 2014. This final annual report also summarizes the results of the relevé vegetation surveys that were conducted in spring 2014 at the treatment sites, as well as the population estimates for Otay tarplant and San Diego thornmint.

This document summarizes maintenance and monitoring activities from September 2007 to March 2009 for the vernal pool and Otay tarplant (Deinandra conjugens) restoration project at the Sweetwater Reservoir. The mitigation project includes 2.70 acres of vernal pool complex (vernal pools and associated uplands) restoration and enhancement, and 4.36 acres of Otay tarplant restoration and enhancement. Approximately 8,201 square feet (ft2) of vernal pool surface area has been restored or enhanced, including 3,929 ft2 of restored vernal pools. All areas that have been restored and enhanced as part of this mitigation effort are becoming established and are progressing toward the Year 5 final success criteria standards.

This third and final annual report provides background information and summarizes the tasks performed during the third year (September 2013 to August 2014) of the Otay tarplant (Deinandra conjugens) and San Diego thornmint (Acanthomintha ilicifolia) restoration and enhancement program in the Chula Vista Central City Preserve. Three quarterly reports have previously been prepared by RECON. The information from these reports is summarized below for tasks completed between September 1, 2013 and August 31, 2014. This final annual report also summarizes the results of the relevé vegetation surveys that were conducted in spring 2014 at the treatment sites, as well as the population estimates for Otay tarplant and San Diego thornmint.

Otay tarplant (Deinandra conjugens) is an endangered plant species found only in the Otay Mesa area. This plant species is considered a narrow endemic species under the Multiple Species Conservation Program (MSCP). Monitoring for this plant was conducted on June 16, 2004, within City-owned land in the Proctor Valley area by City of San Diego staff. The methodology and results of the monitoring are detailed below. The goal of the effort was to continue the annual collection of data for long-term monitoring of Otay tarplant under the MSCP.

Otay tarplant (Deinandra conjugens) is an endangered plant species found only in the Otay Mesa area. This plant species is considered a narrow endemic species under the Multiple Species Conservation Program (MSCP). Monitoring for this plant was conducted on June 2, 2003 within City-owned land in the Proctor Valley area by City of San Diego staff. This is the first year for monitoring of this plant species at this location. However, results from extensive surveys conducted by the U. S. Fish and Wildlife Service (USFWS) on surrounding refuge lands are expected to be available shortly. The methodology and results of the monitoring are detailed below. The goal of the effort was to continue the annual collection of data for long-term monitoring of Otay tarplant under the MSCP.

Summary of rare plant monitoring for Otay Tarplant (Deinandra conjugens)

This project is aimed at assessing the status and genetic diversity of populations of six species of rare plants in San Diego County including Acanthomintha ilicifolia (San Diego thornmint) and Monardella viminea (willowy monardella) in the Lamiaceae, Chloropyron maritimum ssp. maritimum (salt marsh bird's-beak) and Dicranostegia orcuttiana (Orcutt's bird's-beak) in the Orobanchaceae, and Baccharis vanessae (Encinitas baccharis) and Deinandra conjugens (Otay tarplant) in the Asteraceae. The results of this project should directly contribute to the conservation and management of these rare plant taxa in the San Diego MSPA. For each of these species, information on the genetic makeup and diversity across its range is needed to inform potential management actions such as establishing new populations and enhancing existing populations. Previously, verification and scientific voucher specimens were lacking from many occurrences of these six target species across San Diego County. Therefore, the goals of this task are to collect genetic material from as many species’ occurrences as possible and to collect voucher specimens to serve as a long-term resource for studying the populations associated with this project. These collections are useful for future genetic and morphological work to help inform management action. The genetic analyses of these collections will be performed by USGS.

The primary goal of the Rice Canyon Sensitive Plant Species Management Project (project) was to reduce the threat from invasive stinknet (Oncosiphon pilulifer) and illegal trespassing to sensitive plant species. Reducing these threats was a benefit to sensitive animal species that occupy Rice Canyon as well. Sensitive plant species that were the focus of the project include Otay tarplant (Deinandra conjugens), San Diego thornmint (Acanthomintha ilicifolia), and Orcutt’s bird’s-beak (Dicranostegia orcuttiiana). Sensitive animal species that also occur in Rice Canyon include coastal California gnatcatcher (Polioptila californica californica) and coastal cactus wren (Campylorhynchus brunneicapillus sandiegensis) among other Multiple Species Conservation Plan-covered species.

This study presents an approach for identifying and describing geographic areas that support edaphic endemic species and their habitat in a design that enhances resilience and provides opportunities for shifting distributions. We developed conceptual models to inform field studies and management, refined soils and vegetation attributes, and assessed regional population structure and threats. We used results to suggest prioritized locations for surveys, management, potential translocation, and additional conservation or acquisition. The U.S. Geological Survey (USGS) and San Diego Management and Monitoring Program (SDMMP) modeled suitable habitat for the target species under current and future climate scenarios; model results are in a separate report and referenced in this document, as appropriate. Target species include San Diego thornmint (Acanthomintha ilicifolia), thread-leaved brodiaea (Brodiaea filifolia), Otay tarplant (Deinandra conjugens), Dehesa nolina (Nolina interrata), and Parry’s tetracoccus (Tetracoccus dioicus).