Ventura Marsh Milk-Vetch (Astragalus Pycnostachyus Var. Lanosissimus)

Ventura Marsh Milk-Vetch (Astragalus pycnostachyus var. lanosissimus)

Species Status Assessment

Photo credit: Ken Niessen

September 2020 – Version 1

U.S. Fish and Wildlife Service

Ventura, California

Acknowledgements

Core Team

Todd Lemein, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, Ventura, CA

Ken Niessen, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, Ventura, CA

Cat Darst, U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, Ventura, CA

Bjorn Erickson, U.S. Fish and Wildlife Service, Pacific Southwest Regional Office, Sacramento, CA

Table of Contents

EXECUTIVE SUMMARY ...... 10 1 INTRODUCTION ...... 1 1.1 Listing History ...... 1 1.2 State Listing ...... 1 1.3 Approach of the Species Status Assessment ...... 1 2 SPECIES INFORMATION...... 3 2.1 Nomenclature ...... 3 2.2 Description ...... 3 2.3 Distribution ...... 5 2.4 Habitat ...... 9 2.5 Life History ...... 10 3 BIOLOGICAL NEEDS ...... 12 3.1 Historical Evaluations ...... 12 3.1.1 Wilken and Wardlaw (2001) ...... 13 3.1.2 U. S. Fish and Wildlife Service Critical Habitat Primary Constituent Elements (2004) ...... 13 3.1.3 Meyer (2007) ...... 15 3.2 Life Stage ...... 15 3.2.1 Seed ...... 15 3.2.2 Plant ...... 16 3.3 Population Needs ...... 17 3.4 Species Needs ...... 17 3.5 Summary of Biological Needs ...... 18 4 SITE HISTORIES ...... 20 4.1 North Shore ...... 21 4.2 Coal Oil Point Reserve (COPR) ...... 22 4.2.1 Coal Oil Point Reserve Pond ...... 23 4.2.2 Coal Oil Point Reserve Lagoon ...... 25 4.3 North Campus Open Space Restoration Site ...... 27 4.4 Carpinteria Salt Marsh Reserve ...... 27 4.5 McGrath State Beach ...... 29 4.6 McGrath Parcel ...... 31

4.7 Mandalay State Beach ...... 32 4.8 Ormond Beach ...... 33 5 CURRENT DISTRIBUTION, ABUNDANCE, AND MANAGEMENT ...... 34 5.1 North Shore ...... 34 5.2 McGrath Parcel ...... 36 5.3 Carpinteria Salt Marsh ...... 36 5.4 Coal Oil Point Pond ...... 36 5.5 North Campus Open Space Restoration Site ...... 36 5.6 McGrath State Beach ...... 37 6 THREATS AND FACTORS INFLUENCING VIABILITY ...... 37 6.1 Soil Remediation and Residential Development ...... 37 6.2 Anthropogenic and Natural Stochastic Events ...... 38 6.3 Alteration of Hydrology ...... 38 6.4 Competition with Native and Non-native Plants ...... 39 6.5 Herbivory ...... 39 6.6 Disease ...... 40 6.7 Seed Predation ...... 40 6.8 Climate ...... 41 6.9 Factors Influencing Viability ...... 42 7 CURRENT CONDITION (RESILIENCY, REPRESENTATION, REDUNDANCY) 43 7.1 Resiliency ...... 44 7.2 Representation ...... 46 7.3 Redundancy ...... 47 8 FUTURE CONDITION ...... 47 8.1 Land Use and Land management ...... 48 8.3 Climate Change ...... 49 8.3.1 Frequency and Amount of Precipitation...... 49 8.3.2 Average and Extreme Temperatures ...... 50 8.3.3 Shifts in Vegetation Communities...... 50 8.3.4 Sea Level Rise ...... 52 9 FUTURE SCENARIOS ...... 53 9.1 Future Scenario 1 (Continuation) ...... 54

9.2 Future Scenario 2 (Increasing Management) ...... 57 9.3 Future Scenario 3 (Declining Management) ...... 60 10 OVERALL SYNTHESIS ...... 63 REFERENCES ...... 67

List of Figures

Figure 1. Astragalus pycnostachyus var. lanosissimus leaf and inflorescence...... 4 Figure 2. 1896 Topographic map with the esimtaed extent of the “Ballona” occurrences...... 6 Figure 3. Distribution of historical, introduced, natural, and misidentified populations of Astragalus pycnostachyus var. lanosissimus...... 8 Figure 4. Life history diagram...... 12 Figure 5. Designated critical habitat for Astragalus pycnostachyus var. lanosissimus...... 14 Figure 6. Locations of the North Shore site, McGrath State Beach, McGrath Parcel, and Mandalay State Beach...... 22 Figure 7. Reintroduction sites at Coal Oil Point Reserve...... 23 Figure 8. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Coal Oil Point Reserve Pond site...... 25 Figure 9. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Coal Oil Point Reserve Lagoon site...... 26 Figure 10. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Carpinteria Salt Marsh Reserve...... 29 Figure 11. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the McGrath State Beach site...... 31 Figure 12. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Mandalay State Beach site...... 33 Figure 13. Total count of Astragalus pycnostachyus var. lanosissimus at the North Shore site. 36 Figure 14. Total precipitation by water year (Oct-Sept)...... 42 Figure 15. Influence diagram for Astragalus pycnostachyus var. lanosissimus population resiliency...... 43

List of Tables

Table 1 Comparison of identifying characteristics between Astragalus pycnostachyus var. lanosissimus and var. pycnostachyus...... 4 Table 2. Overview of biological needs for Astragalus pycnostachyus var. lanosissimus...... 18 Table 3. Resiliency (2019) of the potentially extant populations...... 45 Table 4. Results of sensitivity and adaptive capacity modeling and the resulting change in suitability of existing habitat for five vegetation macrogroups that Astragalus pycnostachyus var. lanosissimus is associated with...... 51 Table 5. Summary of potential future scenarios influencing the resiliency, representation, and redundancy of Astragalus pycnostachyus var. lanosissimus...... 53 Table 6. Resiliency (Future Scenario 1) of Astragalus pycnostachyus var. lanosissimus populations ...... 57 Table 7. Resiliency (Future Scenario 2) of Astragalus pycnostachyus var. lanosissimus populations ...... 60 Table 8. Resiliency (Future Scenario 3) of Astragalus pycnostachyus var. lanosissimus populations ...... 62 Table 9. Summary of overall resiliency of Astragalus pycnostachyus var. lanosissimus populations under current conditions and three future scenarios...... 64

Table i. Acronyms Used

Acronym Definition ac acre C Celsius CCBER Cheadle Center for Biodiversity and Ecological Restoration CCH1 Consortium of California Herbaria 1 CDFW California Department of Fish and Game CESA California Endangered Species Act cm Centimeters CNDDB California Natural Diversity Database CNPS California Native Plant Society COPR Coal Oil Point Reserve F Fahrenheit ft feet GIS Geographic Information System ha hectare in inches m meter MAND Mandalay State Beach mm millimeters MP McGrath Parcel MSB McGrath State Beach msl mean sea level NCOS North Campus Open Space ORMD Ormond Beach RCP representative carbon pathway RPA resource protection area RSABG Rancho Santa Ana Botanic Garden (now California Botanic Garden) SCA soil consolidation area Service US Fish and Wildlife Service SSA Species Status Assessment UC University of California UCSB University of California Santa Barbara VMMVP Ventura marsh milk-vetch preserve yr year

Table ii. Scientific and Common Names Used

Scientific Name Common Name Plants Abronia spp. sand verbena Acmispon glaber (formerly Lotus scoparius) deerweed Amaryllis belladonna naked lady Ambrosia chamissonis beach bur-sage Ambrosia psilostachya western ragweed Anemopsis californica yerba mansa Artemisia californica California sagebrush Astragalus pycnostachyus var. lanosissimus Ventura marsh milk-vetch Astragalus pycnostachyus var. pycnostachyus northern marsh milk-vetch Atriplex lentiformis big saltbush Baccharis pilularis coyote brush Baccharis salicifolia mule fat Brassica nigra black mustard Bromus spp. brome Cakile maritima sea rocket Calystegia soldanella beach morning glory Camissoniopsis cheiranthifolia beach evening-primrose Carex praegracilis field sedge Carpobrotus spp. iceplant Cortaderia jubata jubata grass Croton californicus desert croton Crassula connata pygmy weed Cryptantha intermedia common cryptantha Descurainia pinnata tansy mustard Distichlis spicata salt grass Ericameria ericoides mock heather Erigeron canadensis horseweed Festuca myuros (formerly Vulpia myuros) rattail sixweeks grass Festuca perennis (formerly Lolium perenne) rye grass Foeniculum vulgare fennel Frankenia salina alkali heath Heterotheca grandiflora telegraph weed Hirschfeldia incana mustard Jaumea carnosa marsh Jaumea Juncus acutus spiny rush Juncus spp. rush Leymus triticoides alkali rye grass Limonium duriusculum European sea lavender Malosma laurina laurel sumac Melaleuca sp. bottlebrush Myoporum laetum ngaio Oenothera elata evening primrose

Table ii. Scientific and Common Names Used

Scientific Name Common Name Oxalis pes-caprae Bermuda buttercup Polypogon monspeliensis rabbitsfoot grass Salicornia pacifica pickleweed Salix exigua narrow-leaved willow Salix lasiolepis arroyo willow Salix spp. willow Scirpus spp. bulrush Suaeda spp. seablite Toxicodendron diversilobum poison oak Typha spp. cattail Animals Anthophora urbana urbane digger bee Apis mellifera honey bee Bombus spp. bumblebee Bombus californicus California bumblebee Bombus crotchii Crotch’s bumblebee Bombus vosnesenskii yellow-faced bumblebee Bruchidae seed beetle Cornu aspersum (formerly) Cantareus common brown garden snail aspersus Hesperiidae skipper butterfly Leptotes marina marine blue butterfly Lepus californicus jackrabbit Megachile perihirta western leafcutter bee Megachile latimus broad-handed leafcutter bee Melissodes spp. long-horned bees Microtus californicus vole Otala lactea milk snail Strymon melinus gray hairstreak butterfly Sylvilagus audubonii desert cottontail Sylvilagus bachmannii brush rabbit Thomomys bottae gopher Xylocopa spp. carpenter bee

EXECUTIVE SUMMARY

The Species Status Assessment for Astragalus pycnostachyus var. lanosissimus (Ventura marsh milk-vetch) describes the life history, distribution, threats, and historical, current, and future condition of the species using the best available information. The primary sources for this assessment include herbarium data provided by the Consortium of California Herbaria, historical species descriptions, the California Natural Diversity Database, reports written by academic institutions, California Native Plant Society, California Department of Fish and Wildlife, U. S. Fish and Wildlife Service, and consulting biologists.

Astragalus pycnostachyus var. lanosissimus historically occurred in habitats associated with dynamic alluvial systems near the coast in Los Angeles and Ventura Counties. The species was believed to have become extinct by the 1960s but was rediscovered in Ventura County in 1997 at a single location planned for development. The establishment of the Ventura Marsh Milk Vetch Preserve and associated buffer area avoided direct loss of the rediscovered population.

The species is a short lived perennial that reaches reproductive age by the second growing season (under favorable conditions, it can be reproductive in the first season) and typically lives between three and five years. The species was found to propagate relatively easily from collected seed and introduction of seed and nursery raised plants was attempted at eight locations in Santa Barbara and Ventura Counties. Astragalus pycnostachyus var. lanosissimus is most successful in areas with a shallow water table (one that is relatively close to the depth of root penetration), or perched water table (an impoundment of water above an impermeable surface generally at a more shallow depth than the actual water table), that can provide moisture during dry summer months when the surface soil is likely dry. Low competition from native and non-native species, likely maintained by periodic flooding, was also identified as a necessary habitat requirement for introductions. Prolonged inundation may also result in mortality. If disturbance does not maintain low competition a population will likely decrease to zero individuals and exist only as an in situ seed bank until habitat conditions again promote germination and survival.

Four populations (three introduced and the rediscovered population) currently contain reproductive individuals of Astragalus pycnostachyus var. lanosissimus. The rediscovered population and an associated introduced population are actively managed through regulatory requirement. A third population contains a single individual after several years of no individuals being observed and a fourth population was introduced in 2019 at a newly developed restoration site. Two additional populations have no reproductive adults, but house a viable seedbank and suitable habitat that could support reproductive adults. Three other populations have no reproductive adults, and habitat conditions that are not likely to support seed germination and seedling survival to reproductive age. Those three populations are considered to be functionally extirpated, meaning that conditions do not currently exist, and are not expected to exist in the future, that would support the species. Between the six extant populations, two have low resiliency, two have moderate resiliency, and two have high resiliency. Populations with low resiliency have poor habitat conditions with less than 10 individuals and are very susceptible to stochastic events. Populations with moderate resiliency have moderate quality habitat and greater than 10 individuals with an assumed adequate seed bank. Populations with high resiliency have high quality habitat, greater than 100 individuals, and an assumed seed bank. Populations with

high quality habitat are generally supported by active management. The reliance on active management suggests that these populations are conservation-reliant. Representation, adaptive capacity, was found to be low because all introduced and existing populations are derived from a single source population. Redundancy, the ability to withstand catastrophic events, was also found to be low because of the low number of populations across a small geographic extent.

Development, changes to site hydrology, competition, herbivory, seed predation, and climate change are threats to the species. Because no populations exist under natural conditions, all are conservation-reliant and the driving determination of the persistence of the species in future scenarios is the type of land use within and surrounding populations, the level of effort implemented to support existing populations, and the level of effort directed towards establishing and maintaining new populations.

We evaluated three future scenarios to estimate a range of plausible outcomes for the species’ persistence in regard to resiliency, representation, and redundancy. The first scenario evaluates the effects of continuing the current management at each of the populations. The second scenario evaluates the effects of increasing management activities and the third scenario evaluates the effect of decreasing management activities. Under the first scenario population resiliency declines or increases in proportion to current management efforts. Representation remains low because all populations are sourced from the same genetic material. Redundancy remains low as no new populations are expected to be found or introduced. In the second scenario resiliency increases as populations not currently actively managed become managed. Representation remains low because no new genetic material is available. Redundancy remains low, but slightly increases with the addition of newly introduced populations. In the third scenario, decreasing management effort leads to extirpation of three populations and lower resiliency in two populations. Representation and redundancy correspondingly decrease with the extirpation of three populations.

There are limited potential introduction sites for Astragalus pycnostachyus var. lanosissimus and the areas where it may be introduced are relatively small. As a result, even under a scenario with increased conservation actions, where introductions are successful and are maintained, populations are susceptible to extirpation due to lack of management. Resiliency of any population is likely to decrease with declining management effort. Representation will remain low unless new different genetic lineages are identified, which is unlikely. Redundancy may increase under an increasing management scenario as new populations are introduced and maintained, but because there is little opportunity to significantly increase the geographic range and extent of the species this would only offer some protection against catastrophic events. Seed in ex situ seed banks and seed that exists at introduction sites that function as in situ seed banks provide a buffer to extinction if all populations decline to zero reproductive individuals. Astragalus pycnostachyus var. lanosissimus is likely to remain conservation-reliant under all future scenarios.

1 INTRODUCTION

This document presents the Species Status Assessment (SSA) for Astragalus pycnostachyus var. lanosissimus (Ventura marsh milk-vetch). We, the U.S. Fish and Wildlife Service (Service), developed this Species Status Assessment for Astragalus pycnostachyus var. lanosissimus to compile and evaluate the best available scientific information regarding the species’ biology and factors that influence the species’ viability.

1.1 LISTING HISTORY

Original Listing FR Notice: 66 FR 27901-27908 Date of Final Listing Rule: May 21, 2001 Entity Listed: Astragalus pycnostachyus var. lanosissimus Classification: Endangered

1.2 STATE LISTING

Astragalus pycnostachyus var. lanosissimus was listed as Endangered by the state of California under the California Endangered Species Act (CESA) in 2000 (CDFW 2019, p. 2; Ikeda and Meyer 2000, entire). The applicable State laws governing the listing of this species and its state regulation are the Native Plant Protection Act of 1977 (Fish and Game Code Chapter 10, 1900- 1913) and the California Endangered Species Act of 1984 (California Code of Regulations, Title 14, Chapter 6, 783.0-787.9; Fish and Game Code Chapter 1.5, 2050-2115.5).

1.3 APPROACH OF THE SPECIES STATUS ASSESSMENT

Following the Species Status Assessment (SSA) Framework (Service 2016, entire), an SSA first begins with a compilation of the best available information about the species (taxonomy, life history, and habitat) and its ecological needs at the individual, population, and species levels. Next, an SSA describes the current condition of the habitat and demographics of the species, and the probable explanations for past and ongoing changes in abundance and distribution. Finally, an SSA forecasts the response of the species to probable future scenarios of environmental conditions.

An SSA uses the conservation biology principles of resiliency, representation, and redundancy as a lens through which we can evaluate the current and future condition of the species (Smith et al. 2018, entire). Ultimately, an SSA characterizes a species’ ability to sustain populations in the wild over time based on the best scientific understanding of current and future abundance and distribution within the species’ ecological settings.

Resiliency describes the ability of populations to withstand environmental stochasticity. Resiliency is positively related to population size and growth rate and may be influenced by connectivity among populations. Generally speaking, populations need abundant individuals within habitat patches of adequate area and quality to maintain survival and reproduction in spite of disturbance.

Representation describes the ability of a species to adapt to changing environmental conditions over time. It is characterized by the breadth of genetic and environmental diversity within and among populations. Measures may include the number of varied niches occupied, gene diversity, heterozygosity, or alleles per locus.

Redundancy describes the ability of a species to withstand catastrophic events. Redundancy is characterized by having multiple, resilient populations distributed within the ecological settings of the species and across its range. Redundancy can be measured by the number of populations and their spatial distribution and degree of connectivity.

This document draws on scientific information from resources such as primary peer-reviewed literature, reports submitted to the Service and other public agencies, species location information in Geographic Information Systems (GIS) databases, and expert experience and observations. It is preceded by and draws upon analyses presented in other Service documents including the original listing (66 FR 27901-27908), the species Critical Habitat designation (69 FR 29081-29100), and a 5-year review (Service 2010, entire). Finally, we coordinated closely with our partners engaged in ongoing research on the species.

2 SPECIES INFORMATION

2.1 NOMENCLATURE

Astragalus pycnostachyus var. lanosissimus is a member of Fabaceae, the pea family. It was first described in 1929 as Phaca lanosissima (Rydberg 1929, pp. 357-358) and subsequently reduced to a variety of Astragalus pycnostachyus, A. pycnostachyus var. lanosissimus in 1932 (Munz 1932, p. 66). The common name of the species, Ventura marsh milk-vetch, reflects the distribution of the species upon its rediscovery in 1997.

2.2 DESCRIPTION

The description by Barneby (1964, pp. 811-813) is used as the primary source for the diagnostic details of Astragalus pycnostachyus var. lanosissimus. Additional detail has been added from observations of the extant occurrences in Ventura County (Meyer 2012, entire). Astragalus pycnostachyus var. lanosissimus is an ascending to erect short-lived herbaceous perennial 40 – 146 centimeters (cm) (16 – 58 inches (in)) tall. It has a thick taproot and multiple erect, reddish stems that emerge from a root crown. The pinnately compound leaves are densely covered with silvery white hairs giving the foliage a grayish-green appearance (Figure 1). Leaves are 3 – 15 cm (1 – 6 in) long and consist of 27 – 39 leaflets, each 5 – 20 millimeters (mm) (0.2 – 0.8 in) long. Floral racemes are dense with white to cream colored flowers forming spike–like heads 2 to 9 cm (1 – 4 in). The peduncle (inflorescence stalk) is 2 – 4 cm (1 –2 in) long. Barneby (1964, p. 813) recorded the flowering period as July through October, although recent observations in Ventura County suggest a current range between May and September, with peak bloom occurring in July (Wilken and Wardlaw 2001, p. 11). Fruits are weakly to moderately dehiscent dry pods that persist on stems (Wilken and Wardlaw 2001, p. 11; Meyer 2007, p. 11). Two morphologies of seed are produced; smaller and smooth light shaded seeds and larger, rough and dark shaded seeds (Smith and Sandoval 2001, p. 2).

Astragalus pycnostachyus var. lanosissimus is most readily differentiated from its close relative Astragalus pycnostachyus var. pycnostachyus by the peduncle length. In var. lanosissimus the peduncle is short (2 – 4 cm (1 – 2 in) long), compared to the longer peduncle of var. pycnostachyus (3 – 10 cm (1 – 4 in) long). Additional differences include the length of the calyx tube, length and shape of the calyx teeth, and the number of ovules (see Table 1 for a comparison of features).

Figure 1. Astragalus pycnostachyus var. lanosissimus leaf and inflorescence.

Table 1. Comparison of characteristics between Astragalus pycnostachyus var. lanosissimus and var. pycnostachyus.

var. lanosissimus var. pycnostachyus

Peduncle length 2 – 4 cm (1 – 2 in) 3 – 10 cm (1 – 4 in)

Calyx tube 3 – 3.5 mm (0.12 – 0.14 in) 3.7 – 5.2 mm (0.15 – 0.20 in)

broad and short; 1.2– 1.5 mm subulate; 1.7 – 3 mm (0.07 – 0.12 Calyx teeth (0.05 – 0.06 in) in) Ovules 8 – 12 4 (2 – 5) Los Angeles, Ventura, Santa Humboldt, Marin, San Mateo Historic Range Barbara (outplanted) Counties Counties

Based on Barneby 1964; Soza 2003; CCH1 2019

2.3 DISTRIBUTION

Herbarium records suggest that the historical distribution of Astragalus pycnostachyus var. lanosissimus occurred in Southern California in association with coastal marshes, lagoons, wetlands, and associated edge habitats within Los Angeles, and Ventura Counties (CCH1 2019, NA). The majority of early collections of the species come from an area that was variously termed “Ballona,” “Rancho Ballona,” “Palms,” “Playa del Rey,” and “Cienega.” This area was all within the Ballona watershed and associated with Ballona Creek and its related seeps, springs, marsh, wetland, and edge habitat. Two large historical wetland complexes “Ballona Lagoon” and “La Cienega” were likely the primary sources of early collections (Rolle 1952, pp. 147-158; Dark et al. 2011, pp. 16-33). These complexes were located around the mouth of Ballona Creek near present day Marina del Rey and between present day Culver City and central Los Angeles (Figure 2).

Collections made by S. B. and W. F. Parish in either 1881 or 1882 point to the Ballona area as the type, and, at that time sole, location of the species. An isotype of Astragalus pycnostachyus var. lanosissimus held at The Academy of Natural Sciences of Drexel University notes a location of “La Bolsa” for an 1881 S. B. and W. F. Parish collection (PH00023086). Previously, this location had been assumed to refer to the wetland complex of the Bolsa Chica Ecological Reserve in Orange County. Duplicate specimens collected by S. B. and W. F. Parish (including other isotypes) suggest that this assumption is an error. The duplicate specimens of Astragalus pycnostachyus var. lanosissimus collected by S. B. and W. F. Parish at this time were given collector number 1117, and a review of collector numbers surrounding this collector number and collection date suggest that the Parishes never traveled to the Bolsa Chica wetlands of present day Orange County to make collections (CCH1 2019, NA). This error had previously been noted by Barneby (1964 p. 813) who suggested that “La Bolsa” was likely equal to “Ballona.” Between 1884 and 1951, Astragalus pycnostachyus var. lanosissimus was collected several times in the Ballona area by collectors using the same variety of location names. Collections from the Ballona area stop after 1951, with the last collection being from Playa del Rey, the southwestern extent of Rancho la Ballona.

Figure 2. 1896 Topographic map with the estimated extent of the “Ballona” occurrences. Estimated extent based data from Dark et al. 2011. Orange markers show CNDDB estimated locations of historical occurrences, including locations referred to as "Ballona," "Palms," "Rancho Ballona," "Cienega," and “Playa del Rey.” It is believed all collections are from same alluvial system.

The remaining collection records are from within Ventura County at two locations, near Port Hueneme (1901 – 1927) and the mouth of the Santa Clara River near McGrath State Beach

(1967), both located within the geographic extent of the Oxnard Plain. The Oxnard Plain is characterized by soil morphology and topography that resulted from sedimentation and channel migration of the Santa Clara River over geologic time (Beller et al. 2011, p. 72). The last historical collection of Astragalus pycnostachyus var. lanosissimus was made at the mouth of the Santa Clara River near McGrath State Beach in 1967. Barneby (1964, p. 813) noted that the occurrences from Los Angeles County (i.e. “Ballona”) were likely extirpated by 1951 based on his surveys of remaining suitable habitat. The species was believed extinct at all historical locations by the 1980s (Soza et al. 2003, p. 4).

In 1997, Astragalus pycnostachyus var. lanosissimus was rediscovered during botanical surveys for a proposed housing development near McGrath State Beach in Ventura County (known as the North Shore site). The North Shore site had been previously used for the disposal of oil waste products from 1955 to 1981 and it is possible that the plants germinated from seed that was contained in fill material that had been used at the site (Soza et al. 2003, p. 5). The species has continued to persist at the North Shore site with supplemental watering and management activities. In Santa Barbara County, plants have been introduced to the Coal Oil Point Reserve (pond and lagoon sites), North Campus Open Space (NCOS) restoration site, and Carpinteria Salt Marsh Reserve. In Ventura County, plants have been introduced to McGrath State Beach, a mitigation site on City of Oxnard property (McGrath Parcel), Mandalay State Beach, and Ormond Beach (Figure 3). Introductions have typically required supplemental planting and/or maintenance to be successful.

In 2019 we consider there to be six extant populations (the North Shore site, and five introduction sites). Three historical introductions have failed, do not have suitable habitat, and are considered extirpated. We only consider populations that currently have, or are likely to have, suitable habitat and a viable seedbank as extant. Reintroduction sites where habitat was found to not be suitable and where a seed bank is unlikely to persist, or where germination potential and survival is low, are considered extirpated. With this definition, the North Shore site, Coal Oil Point Reserve (COPR) Pond, North Campus Open Space (NCOS) restoration site, Carpinteria Salt Marsh Reserve, McGrath State Beach, and McGrath Parcel, all contain extant populations. The remaining introduced populations at the COPR lagoon site, Mandalay State Beach, and Ormond Beach are considered extirpated due to lack of habitat, non-viable seed bank, and no surviving adults.

Figure 3. Distribution of historical, introduced, natural, and misidentified populations of Astragalus pycnostachyus var. lanosissimus. COPR (Coal Oil Point Reserve), NCOS (North Campus Open Space), CSMR (Carpinteria Salt Marsh Reserve), MSB (McGrath State Beach), MP (McGrath Parcel), ORMD (Ormond Beach), NS (North Shore).

2.4 HABITAT

The habitat characteristics of the historic populations in Los Angeles and Ventura Counties are not well understood due to the lack of habitat descriptions and vague location information associated with historical collections. We do know that prior to the development of Los Angeles and Oxnard all historical locations occurred within dynamic alluvial habitats and adjacent wetlands and transitional habitats. Salix exigua (narrow-leaved willow), S. lasiolepis (arroyo willow), Baccharis salicifolia (mule fat), and B. pilularis (coyote brush), are likely indicators of suitable habitat. The “Ballona” records from Los Angeles County were associated with historical wetland complexes along Ballona Creek, “La Cienega” and “Ballona Lagoon.” These wetland complexes were large and fed primarily by springs and subsurface flows within the Ballona Watershed. There is evidence that even the lower Ballona Lagoon was only seasonally opened to the Pacific Ocean and minimally tidally influenced (Dark et al. 2011, pp. 22-29). Vegetation communities were likely dynamic, changing in composition and abundance with annual precipitation and subsequent flooding. In Ventura County, based on historical topographic maps (1904), the Port Hueneme records are associated with water impoundments in back dune complexes and the McGrath occurrence is associated with the floodplain of the Santa Clara River near its mouth. Historical vegetation types associated with these areas include dunes, coastal sage scrub, salt and tidal flats, tidal marshes, alkali flats and meadows, wet meadow, freshwater marsh, ponds, vernal pools, willow thickets, oak and sycamore forests, and grasslands (Beller et al. 2011, pp. 47-50; Dark et al. 2011, pp. 15-18). It is likely that within the past 200 – 500 years the Santa Clara River channel entered the ocean at Port Hueneme and migrated north to its present location by the 1800s (Beller et al. 2011, pp. 66-72). Despite that large migration, the general course of the Santa Clara River has remained in relatively the same location since 1870 while exhibiting large variations in the location of the main river channel. Vegetation communities associated with the Santa Clara river similarly shifted extent and location dependent upon the most recent flood and current position of active river channels. Aerial photographs beginning in 1927 suggest that major shifts in vegetation communities occurred at least every decade. During the dry season, portions of the main channel of the Santa Clara River may have ceased to have surface flows while other reaches maintained perennial surface flows. Similarly, tributaries likely did not directly join the main channel of the river, instead fanning out to indistinct washes and being connected through subsurface flow (Beller et al. 2011, pp. 76-77). While only a portion of the river may have exhibited year-round surface flows, the entire basin was hydrologically connected with subsurface flows.

The contemporary landscape where Astragalus pycnostachyus var. lanosissimus exists has been altered by a history of varying land use. The North Shore site (where the species was rediscovered) had been used as an oil waste disposal site between 1955 and 1981 (LFR 2009, p. 5). A portion of the McGrath Parcel (location of the surviving outplanted population in Ventura County) had been used as a go-kart track from the 1960s until 2006 (Arcadis 2019, p. 1-2). Both sites have been actively restored to dune, coastal sage scrub, and willow scrub vegetation communities, and both are in close association with a high water table, although neither population is considered natural. Both sites are managed specifically to promote Astragalus pycnostachyus var. lanosissimus, including invasive plant species control, herbivore control, soil moisture monitoring, subsurface and surface irrigation, and woody vegetation control. Common species found at each site are Salix lasiolepis, Artemisia californica (California sagebrush), Baccharis pilularis, B. salicifolia, and Ericameria ericoides (mock heather).

At the North Shore site, between 2006 and 2009, ponds for waste disposal were excavated, filled with oil waste products, then filled with sand and capped with bentonite. Dunes and coastal sage scrub likely dominated the North Shore site prior to its use as an oil waste disposal site (Arcadis 2017, Appendix F, Appendix B’ p. 1). Soil samples collected in 1997 and 2009 indicate that where Astragalus pycnostachyus var. lanosissimus occurs the depth to oil affected soil ranges from 0.2 m (0.66 ft) – 1.1 m (3.75 ft) below the soil surface. Soil above the oiled layers is primarily sand (93 – 96 percent) with small proportions of silt and clay. Excavation of the root zone of a single plant in 1997 found that roots were restricted to soils above the oiled layer and that roots within the oiled layer were necrotic. Soil moisture monitoring and annual surveys suggests that optimum soil moisture for the species survival is 70 percent (when using a capacitance type sensor) at 46 cm (18 in) below ground surface (Arcadis 2018, p. 3-5; Arcadis 2017, Appendix E, p. 10). Soil moisture has been measured in a variety of methods including measuring the mass of water loss on drying (produces gravimetric soil moisture), soil saturation (amount of water needed to bring a field sample to complete saturation), capacitance sensors (in situ measurements of percent soil moisture), and time domain reflectometry sensors (in situ measurements of volumetric soil moisture content). The variety of methods make comparison difficult and conversion between methodologies is unreliable. In this document we present the soil moisture as reported in the source document and note the method used. The North Shore and McGrath Parcel have the longest continuous soil moisture monitoring and have used capacitance instrumentation. The range estimates for optimum soil moisture are based on that data. Survivorship decreases both as soil moisture decreases and in cases of complete inundation (i.e., flooding resulting in standing water). At the North Shore site, it is possible that the shallow oil contaminated soil creates a hydrophobic layer causing the perching of surface water at a depth where it can be used by the plant but not so shallow that the moisture is lost to evapotranspiration (Meyer 2007, pp. 60-61).

The McGrath Parcel and McGrath State Beach sites are still subject to flooding during periods of high precipitation resulting in McGrath Lake overflowing to the east where water can pond. This has been observed in to occur since the first outplanting in 2004 at McGrath State Beach and indicates that some level of natural disturbance processes is still possible at the site. The Coal Oil Point Reserve (COPR) pond site and North Campus Open Space restoration site are part of the same lagoon system and may become inundated during periods of high precipitation and/or during storm surges coupled with high tides. The COPR pond site may also experience flooding from the adjacent pond (not tidally connected to Devereaux Lagoon). The population at Carpinteria Salt Marsh Reserve may become inundated generally only during the highest high tides because of its position at the upland margin of the salt marsh.

2.5 LIFE HISTORY

Seed germination may begin in February, continuing through May, and decline in June (seedlings can be readily identifiable as an Astragalus species by March with the first emerging true leaf) (Wilken and Wardlaw 2001, p. 13). Seedlings are generally found within 1 – 2 m (3.3 – 6.6 ft) from adult plants but seeds may be moved greater distances by flood waters (Meyer 2012, p. 5). Generally, individuals do not flower in their first year, but may if there is adequate moisture and stem heights reach greater than 60 cm. About half of observed individuals will flower in their second year and all flower in their third year. Flowers may emerge as early as

June, peaking in July, and continuing through September (Wilken and Wardlaw 2001, p. 11). Skipper butterflies (Hesperiidae), bumblebees (Bombus spp., B. californicus, B. crotchii, B. vosnesenskii), long-horned bees (Melissodes spp.), leafcutter bees (Megachile perihirta, M. latimus), digger bees (Anthophora urbana), carpenter bees (Xylocopa spp.), marine blue butterflies (Leptotes marina), gray hairstreak butterflies (Strymon melinus), and honey bees (Apis mellifera) have been observed visiting open flowers, although the exact pollination strategy is not known (Wilken and Wardlaw 2001, p. 11; Meyer 2007, p. 12-13; Meyer 2012, p.5; Calderon 2020, p. 1). Wilken and Wardlaw (2001, p. 12) found the species is self-compatible (autogamous) although fruits and seeds per fruit were reduced in self-pollinated flowers compared to open-pollinated flowers. Fruits continuously mature through the flowering season, generally concluding by September, although sometimes extending through November. Fruits are weakly dehiscent and semi-persistent on stems (Wilken and Wardlaw 2001, p. 11; Meyer 2007, p. 11). Soil samples taken from beneath adult plants at the North Shore site found seed present in the soil and fruits with developed seeds may remain on the plant into the next growing season. Two morphologies of seed are produced, smaller, smooth, olive green to brown seeds and larger, rough, and darker (color unspecified) seeds (Smith and Sandoval 2001, p. 2). The larger rough seeds were observed to germinate readily without any treatment, unlike the smaller smooth seeds. If soaked in hot water before planting, the smaller smooth seeds had higher germination rates after three weeks than the larger rough seeds (Smith and Sandoval 2001, pp. 4- 6). The two different germination rates suggest two strategies for maintaining and expanding population sizes. The more readily germinable seed facilitates reestablishment of new plants annually and locally under favorable conditions while the small and smooth seed likely persist as a seed bank until environmental conditions promote germination (e.g. ground disturbance, flooding).

Individual plants commonly live for three to five years but may live past 10 years (Meyer 2012, p. 6, Carroll 2020, pers. com.). Dense patches of individuals may arise from a single parent from recently produced seed. These dense patches may persist for one to two seasons before thinning due to competition and herbivory from rabbits (possibly Sylvilagus bachmannii, S. audubonii), or jackrabbits (Lepus californicus) (Meyer 2007, p. 126).

Populations of Astragalus pycnostachyus var. lanosissimus are comprised of adult plants for only as long as suitable habitat conditions allow. As conditions become unsuitable the population may persist as a seed bank until favorable conditions return. The species colonizes, or reemerges, in recently disturbed areas where competition with competing vegetation is low or absent and a perched water table is present (biological needs are expanded upon in Section 3). Seed germinates following a disturbance event (flooding, ground disturbance) and a subset of plants survive to be reproducing adults, commonly surviving for three to five years. This cycle continues as long as competition from neighboring plants (native, non-native, or conspecific) remains low. Simultaneously after a disturbance event, longer-lived plants such as Salix spp. (willows), shrubs (e.g. Baccharis pilularis, Artemisia californica, Ericameria ericoides), and depending on water availability, mat forming rhizomatous herbaceous species (e.g. Juncus spp. (rush), Typha spp. (cattail), Distichlis spicata (salt grass)), are recruiting to the area. With the establishment of these species and the resulting shift in vegetation community, the numbers of Astragalus pycnostachyus var. lanosissimus decline until the population persists only as a seed bank with no reproducing adults (Figure 4).

Figure 4. Life history diagram.

3 BIOLOGICAL NEEDS

The biological needs of Astragalus pycnostachyus var. lanosissimus have been estimated based on the physical characteristics of remnant historical habitat, assumed suitable habitat, and on observations from reintroduction attempts and the management of the North Shore site. The biological needs were first evaluated by Wilken and Wardlaw (2001, entire). In 2004, Wilken and Wardlaw’s criteria were used as the foundation to establish primary constituent elements as part of the critical habitat designation (Service 2004, 69 FR 29081-29100). In 2007, CDFW proposed amended biological needs based on the successes and failures of reintroduction efforts and evaluation of the North Shore site (Meyer 2007, pp. 161). In the following sections, previously identified biological needs are summarized, followed by our current understanding of biological needs at different life stages (seed, plant), population needs, and species needs.

3.1 HISTORICAL EVALUATIONS

The historical evaluations of the biological needs of Astragalus pycnostachyus var. lanosissimus are provided here as described in the source documents. The historical biological needs are presented as criteria that were used to evaluate suitable habitat for past reintroduction efforts. Criteria that have continued to be considered necessary are repeated across evaluations by their

authors, while other criteria have been amended, removed, or added by their authors based on more current observations.

3.1.1 Wilken and Wardlaw (2001)

Wilken and Wardlaw (2001, p. 16) developed their criteria after evaluation of both the North Shore site and locations where the close relative Astragalus pycnostachyus var. pycnostachyus occurs between San Mateo and Marin Counties, California. Their criteria were then used to evaluate potential outplanting locations.

1. Dominant vegetation composed primarily of native shrubs, 50–75% cover. 2. Low herbaceous cover composed of scattered annuals or herbaceous perennials. 3. Close proximity of fresh or brackish water (evidenced by stream channel or Salix spp., Baccharis salicifolia, Typha spp., Scirpus spp. (bulrush). 4. Relatively compact, stable sandy substrate. 5. Similar soil chemical composition to North Shore site. 6. Nearby native vegetation that supports potential pollinators.

3.1.2 U. S. Fish and Wildlife Service Critical Habitat Primary Constituent Elements (2004)

Approximately 420 acres (170 hectares) of critical habitat have been designated between Santa Barbara and Ventura Counties, California (Figure 5; Service 2004, 69 FR 29081). The designated critical habitat does not necessarily represent the entirety of the potential range of the species or all of the suitable habitat within the current range of the species. The primary constituent elements represent the Service’s 2004 understanding of the species biological needs using the best available scientific information at the time of designation (Service 2004, 69 FR 29088).

1. Vegetation cover 50–75%, primarily of native species including Baccharis salicifolia, Baccharis pilularis, Salix lasiolepis, Lotus scoparius (now Acmispon glaber (deerweed)), Ericameria ericoides. 2. Low densities of non-native annual plants and shrubs 3. Presence of high water table, fresh or brackish, evidenced by channels, sloughs, or depressions that may support stands of Salix lasiolepis, Typha spp., and Scirpus spp. 4. Soils that are fine-grained, composed primarily of sand with some clay and silt, yet are well drained. 5. Soils that do not exhibit a white crystalline crust that would indicate saline or alkaline conditions.

Figure 5. Designated critical habitat for Astragalus pycnostachyus var. lanosissimus. COPR (Coal Oil Point Reserve), NCOS (North Campus Open Space), CSMR (Carpinteria Salt Marsh Reserve), MSB (McGrath State Beach), MP (McGrath Parcel), ORMD (Ormond Beach), NS (North Shore).

3.1.3 Meyer (2007)

Meyer (2007) proposed additional and amended criteria specifically to address gaps in criteria suggested by Wilken and Wardlaw (2001, p. 16). The amended criteria add habitat detail and address herbivory that both potentially reduces the cover of herbaceous competitors and the health and abundance of Astragalus pycnostachyus var. lanosissimus (Meyer 2007, p. 161-163).

1. Planting locations near the coast with a maritime influence including mild temperatures, higher humidity, and periodic fog. 2. Transitional zone between wetlands and drier habitats with lower herbaceous cover and generally on flat to gently sloping ground. 3. Perched fresh or brackish water table between 50 – 120 cm from surface. 4. Bare ground or bare ground with light to moderate litter covering 5 – 25% of area for seedling/juvenile recruitment. 5. Gopher bioturbation is absent or occurs at very low levels. 6. Plantings adjacent to vegetation higher than 0.5 m should be open, preferably on three sides, to low growing vegetation to reduce herbivory. 7. Locations distant from shrub cover or dense patches of taller herbaceous vegetation may have reduced herbivory. 8. Locations protected from Santa Ana winds and with more days of fog are likely to experience less drying. 9. Shrub cover ranging from 20 – 40% but shrubs as individuals or in small groups and not solid stands. 10. Rhizomatous perennial facultative to obligate wetland thatch-producing plants may be present, but have low cover. 11. Ambrosia psilostachya (western ragweed) is present with nearby wetland species. 12. Non-alkaline wetland indicator species present, very low cover of halophytes and salt marsh indicator species. 13. Enough space to allow movement of seed and recolonization following flood events. 14. Soils contain some clay and silt with organic matter to improve water retention. 15. Salinity lower than 10 mmhos/cm.

3.2 LIFE STAGE

The biological needs of the species by life stage (seed, juvenile/reproductive plant) as currently understood are given in Sections 3.2.1 and 3.2.2. The biological needs are based on the historical evaluations (Section 3.1) and more recent observations, reports, and data.

3.2.1 Seed

If there is a seed bank where there are currently no plants, seed may germinate following disturbance (Meyer 2007, pp. 101-103). Historically, natural disturbances that could lead to germination were likely flood events that resulted in newly bare ground, vegetation composition change, and rearrangement of a main channel, side channels, and tributaries of alluvial systems (Beller et al. 2001, pp. 44-45). Agriculture, urbanization, and residential development have resulted in flood control infrastructure that eliminates flood events of necessary magnitude and frequency to allow disturbances to continue under natural temporal scales (Beller et al. 2001, pp.

38-45). In the absence of the natural flood regime, anthropogenic ground disturbance resulting in similar effects may induce seed germination. Locally dispersed seed from existing populations will germinate each season without disturbance. This is may be due to variation in seed morphology with smaller smooth seed being dormant until disturbance (creating an in situ seed bank) and the larger rough seed germinating without disturbance (Smith and Sandoval 2001, p. 9).

Adequate moisture, soil type and texture, light availability, and low competition are required for seed germination. Wilken and Wardlaw (2001 p. 13) noted that seeds were observed to germinate in either minor depressions with organic debris and duff away from existing plants, or in flat sites with organic debris and duff under the shade of existing plants. Seedlings at current restoration sites appear to germinate in areas of bare ground regardless of topography as long as adequate soil moisture is present. Soil moisture can be measured in a variety of methods and different methods produce percent moisture values that are not directly comparable. Seventy percent soil moisture, when using a capacitance based instrument, has been suggested as the optimal amount for the species (Arcadis 2017, Appendix E, p. 10). When using gravimetric methodologies moisture values of introduction sites have ranged between 1 percent and 25 percent (Soza et al. 2003, p. 11). In general, mature plants may tolerate short periods of sub- optimum soil moisture but will senesce and die with sustained inadequate soil moisture. Predominantly sandy soil with 10 – 20 percent of silt provides adequate substrate for germination. In controlled germination trials seed will germinate with scarification, hot water soak, and cold water soak pretreatments replicating the flooding and ground disturbance necessary for germination of a dormant seed bank observed under natural conditions (Smith and Sandoval 2001, entire; RSABG 2012, entire).

3.2.2 Plant

Following germination, a juvenile plant requires soil moisture between 10 to 25 percent (gravimetric) or 70 to 80 percent (capacitance) at 30 – 45 cm (12 – 18 in) below ground surface (Soza et al. 2003, p. 11; Meyer 2012 p. 14; Stratton 2020 pers. com.), and low competition from conspecifics and native and non-native herbs and shrubs. The optimal soil moisture is supported by a shallow persistent water table and that has been measured at reintroduction sites as between 48 and 128 cm (19 – 50 in) below ground surface. Depth to the water table may vary with seasonal precipitation, periods of drought, and ground water diversion (Meyer 2007, p. 58-65). Inundation lasting more than ten days (and likely less, but has not been observed) results in complete mortality of juvenile and reproductive individuals. However, seed will survive inundation, and germination following dry down is likely (Meyer 2007, pp. 56-58). Juveniles growing in direct shade of neighboring plants may have lower survival rates than those in direct sun or partial shade (Meyer 2012, p. 25). Survival increases in soils with lower salinity. High cover of salt marsh plant species such as Salicornia pacifica (pickleweed), Frankenia salina (alkali heath), Jaumea carnosa (marsh Jaumea), Distichlis spicata, and Atriplex lentiformis (big saltbush) may all indicate areas with salinity too high for survival of Astragalus pycnostachyus var. lanosissimus. Regular tidal inundation and salt crusts are also visible indicators of poor habitat from high salinity. Juvenile and reproductive plants cannot tolerate persistent hot temperature, surviving best in coastal sites characterized by high humidity, periodic fog, and cooler summer temperatures (Meyer 2007, p. 56).

Reproductive individuals have the same biological needs as juveniles with the addition of needing a pollination mechanism in order to produce viable seed. Astragalus pycnostachyus var. lanosissimus is self-compatible, although seed production is higher when flowers were not autogamously self-pollinated (Wilken and Wardlaw 2001, p. 12). Bumble bees are the most commonly observed floral visitor. Skipper butterflies, carpenter bees, marine blue butterflies, gray hairstreak butterflies, and honey bees have also been observed visiting mature flowers (Wilken and Wardlaw 2001, p. 11; Meyer 2007, p. 12-13; Meyer 2012, p. 5).

3.3 POPULATION NEEDS

A population of Astragalus pycnostachyus var. lanosissimus is defined here as a group, or groups, of individuals that have the capability to interbreed through exchange of pollen and are close enough geographically that physical and environmental effects (e.g. flood events) are similar within a population but different between populations.

A resilient population can sustain withstand environmental stochasticity, sustaining populations through favorable and unfavorable conditions. Resilient populations need abundant individuals within habitat patches of adequate area and quality to maintain survival and reproduction. Resilient populations of Astragalus pycnostachyus var. lanosissimus require natural disturbance processes that result in redistribution of the seed bank, creation of bare ground, and a recharged groundwater table. We do not know the frequency of disturbance events at the historical locations that may have maintained populations of Astragalus pycnostachyus var. lanosissimus at Ballona, Hueneme, or near McGrath Beach and the Santa Clara River. Contemporary estimates of vegetation community shifts due to flooding are estimated to be approximately decadal. It is possible that populations were ephemeral in the sense that the number of above-ground individuals within a population slowly declined to zero as habitat conditions became unfavorable due to increases in shrubby or wetland vegetation that outcompeted Astragalus pycnostachyus var. lanosissimus. At zero above-ground individuals the population exists as a seed bank waiting for favorable germination conditions that would have been brought on by a disturbance event such as a flood. Such a disturbance regime needs the landscape to operate in a natural, unrestrained manner. This requires large sections of alluvial systems to periodically flood, resulting in channel migration, sediment movement, vegetation community composition change, creation of bare ground, and recharged water table.

3.4 SPECIES NEEDS

At the species scale, all populations of Astragalus pycnostachyus var. lanosissimus are considered together. The species needs redundancy, multiple populations that are spatially discrete so that negative biological (e.g. disease, herbivory), environmental (e.g. changes in land use), or physical (e.g. drought) factors do not affect all populations equally. Similarly, a spatially diverse range of populations promotes the chance that natural disturbance events occur in areas where a seed bank persists and facilitates population reestablishment. The species also needs representation, breadth of genetic and ecological diversity, to adapt to both near-term and long- term novel changes in its physical and biological environment.

3.5 SUMMARY OF BIOLOGICAL NEEDS

Astragalus pycnostachyus var. lanosissimus needs habitat and population characteristics that allow the persistence of populations through periods of favorable and unfavorable conditions. A resilient population has the population characteristics described under the self-sustaining column in Table 2. Low resiliency populations will have characteristics under the declining population column in Table 2. High resiliency populations will be better able to withstand environmental stochasticity compared to low resiliency populations.

The species also needs redundancy, multiple populations that are spatially discrete so that catastrophic events do not affect all populations equally. Lastly, genetic diversity (representation) should encompass the range of the species including spatially and ecologically unique populations.

Table 2. Overview of population needs for Astragalus pycnostachyus var. lanosissimus.

Self-sustaining Moderate Survival Declining Population

Stabilized environment Periodic (decadal?) Infrequent or managed with increasing large scale disturbance Dynamic disturbances that result perennial vegetation resulting in landform Environment in vegetation cover, late successional and vegetation composition change. vegetation composition change. communities.

25 – 50 or 75 – 85 percent; some bare <25 or >85 percent. ground may be too Too little canopy cover 50 – 75 percent; exposed, or bare leads to desiccation, or remaining bare ground ground for colonization high herbaceous and/or allows colonization may be minimal with shrub canopy cover is Vegetation while associated cover herbaceous and/or too dense to support Cover moderates shrub canopy cover germination and adult environmental becoming too dense for plant survival. Late conditions. Early seedling survival. Mid successional habitat successional habitat. successional habitat with higher percent with higher percent cover. cover.

Table 2. Overview of population needs for Astragalus pycnostachyus var. lanosissimus.

Self-sustaining Moderate Survival Declining Population

Baccharis salicifolia, Increasing cover of Salix lasiolepis, Salix Monoculture of any invasive species such exigua, Anemopsis invasive species, high as Carpobrotus spp., californica, Juncus spp. density mixes of non- Bromus spp., or other wetland species native species, Myoporum laetum; nearby indicating dominance of obligate Associated increasing density of presence of shallow wetland species, or Species native shrubs such as water table. Dry complete transition to Artemisia californica margins of suitable native coastal sage or Salix spp.; or habitat indicated by scrub or other woody moderate cover of Artemisia californica, community with high obligate wetland Baccharis pilularis, coverage. species. Ericameria ericoides.

Shallow water table Ground water level within floodplain of may vary significantly nearby creek, river, or between periods of Ground water is too lake; alternatively a Water Table drought and flooding deep and supplemental perched water table causing habitat to be watering is needed. above a shallow suitable only for short subsurface restrictive periods. layer

Soil Moisture at 50 – 85 percent (70 < 25 percent or > 85 18 Inches 25 – 50 percent percent optimum) percent (capacitance)

Greater than 100 adult Fewer than 10 adult individuals. Cross Between 100 and 10 individuals present Reproductive pollination with other adult individuals resulting in high Adults1 reproductive adults is present. probability of self likely. fertilization.

Table 2. Overview of population needs for Astragalus pycnostachyus var. lanosissimus.

Self-sustaining Moderate Survival Declining Population Seed bank declining Possibly present due to observed because of historical Assumed or germination coupled population maintenance demonstrated present in Seed Bank with mortality prior to but declining due to high volume. Seed bank reproduction. Seed age or predation. replenished regularly. bank replenished Inadequate or no seed sporadically. bank replenishment. 1 We recognize that 100 adult individuals is less than published minimum viable population sizes (Traill et al. 2007, entire; Flather et al. 2011, entire; Jamieson and Allendorf 2012, entire). Because of the presence of a seed bank, the adult individuals do not represent the entire population. In addition, active management activities can positively affect the likelihood of persistence for a given population size.

4 SITE HISTORIES

Upon rediscovery of Astragalus pycnostachyus var. lanosissimus at the North Shore site in 1997, site assessments for reintroduction locations began. By 2001, Wilken and Wardlaw (2001, entire) had evaluated the North Shore ‘natural’ location and multiple locations of the closest relative Astragalus pycnostachyus var. pycnostachyus to inform reintroduction efforts. University of California (UC) Coal Oil Point Reserve, UC Carpinteria Salt Marsh Reserve, Emma Wood State Beach (near the Ventura River mouth), McGrath State Beach near McGrath Lake, Mandalay State Beach, and Naval Base Ventura County Point Mugu, were all considered as potential candidates for reintroduction of Astragalus pycnostachyus var. lanosissimus. Emma Wood State Beach was determined not to have sufficient habitat and was dropped from consideration. No plants were introduced at the Naval Base Ventura County, despite the presence potential habitat, because of regulatory concerns (Jensen 2007, p. 56). Ormond Beach, on land owned by the California Coastal Conservancy and The Nature Conservancy, was added as a location in 2004 because the California Department of Parks and Recreation had requested no additional outplanting at McGrath State Beach (Meyer 2007, p. 22). The California Native Plant Society reevaluated initial introduction sites and additional potential reintroduction sites in 2007 (Jensen 2007, pp. 36-48). No reintroductions occurred at the additionally considered areas and they are not discussed further in this species status assessment. In October 2019, the Cheadle Center for Biodiversity and Ecological Restoration (CCBER) at UC Santa Barbara began planting Astragalus pycnostachyus var. lanosissimus at the North Campus Open Space (NCOS) restoration site. The NCOS restoration site was not included in prior site assessments for reintroduction because it had previously been a golf course until restoration began in 2017 (CCBER 2018, p. 6).

Both UC Reserves (Coal Oil Point Reserve and Carpinteria Salt Marsh Reserve), as well as the NCOS restoration site, are located in southern Santa Barbara County. All other reintroduction sites are located in Ventura County. The lack of sufficient suitable sites in Ventura County led to the consideration of sites in Southern Santa Barbara County despite there being no records of

Astragalus pycnostachyus var. lanosissimus north of McGrath State Beach in Ventura County. This slight range extension was agreed to be reasonable considering the habitat loss throughout the historical range (Meyer 2007, p. 22).

4.1 NORTH SHORE

The North Shore site is located at the corner of 5th Street and Harbor Boulevard in Ventura County. The name refers to “North Shore at Mandalay Bay,” a planned 90 acre residential development surrounding the occurrence. Astragalus pycnostachyus var. lanosissimus was rediscovered in 1997 at the North Shore site during surveys for environmental compliance of remediation of oil waste in preparation for residential development. The North Shore site is in close proximity to three introduction sites, McGrath State Beach, McGrath Parcel, and Mandalay State Beach (Figure 6). The area had been used as a waste site for oil products from the 1950s through 1981 (LFR 2009, p. 5). Vegetation was absent at the site following cessation of waste disposal and the site remained unused from 1982 through the mid-1990s (Ikeda and Meyer 2000, p. 12). During this period a mix of weeds and native dune vegetation colonized the site. Ikeda and Meyer (2000, p. 14) suggested three possibilities for how Astragalus pycnostachyus var. lanosissimus came to exist at the North Shore site:

1. Seed may have been imported as fill material from another location; 2. Seed may have been present at the site and redistributed over the surface as oil waste disposal ceased; 3. The species may have existed near the site and dispersed to its present location.

Oral history of the closure of the oil waste disposal suggest that seed was likely present on site and was redistributed over contaminated soils to the current location (Ikeda and Meyer 2000, p. 14), but it is likely that the true source of the seed will never be known.

The North Shore site remains the only known population of Astragalus pycnostachyus var. lanosissimus to have established naturally from a seed bank without reintroduction activities. The North Shore site has never been planted although it has been irrigated and non-native species have been managed since 2009. The location was not known to be a historical occurrence and the land use of the area (oil waste disposal) did not suggest it was suitable habitat for the species, despite being only 2.5 mi south of the last known observation of the species. Prior to the development of industrial, agricultural, commercial, recreational, and residential uses, the habitats between the last known observation and the North Shore site were likely similar in character. The North Shore site remained unmanaged from the time of discovery in 1997 through 2009. In 2009, soil moisture monitoring wells and an irrigation system were installed following the decline in survivorship of adult plants. Since 2009 weed management and irrigation have occurred annually and the number of adult plants has increased. No supplemental planting of Astragalus pycnostachyus var. lanosissimus has ever occurred at the North Shore site (Carroll 2019, pers. comm.). The North Shore site is protected under agreements between the developer, CDFW, CNPS, and the California Coastal Conservancy that require the population to be permanently protected (Arcadis 2018b, pp. 3-7).

Figure 6. Locations of the North Shore site, McGrath State Beach, McGrath Parcel, and Mandalay State Beach.

4.2 COAL OIL POINT RESERVE (COPR)

The Coal Oil Point Reserve (COPR) covers 170 acres (69 hectares) adjacent to the West Campus of the University of California Santa Barbara (UCSB) surrounding Devereux Lagoon. Habitat

types include freshwater marsh to tidal lagoon, dune and dune scrub, and coastal sage scrub (Sandoval and Swarbrick 2015, pp. 12-13). Elevation of Astragalus pycnostachyus var. lanosissimus reintroductions sites are located at 10 – 20 ft above mean sea level (msl). Reintroduction was attempted at two locations within the reserve: the Pond site and the Lagoon site (Figure 7). The Pond site is located in a back dune area between dunes and a groundwater- fed freshwater pond. The area floods periodically during periods of heavy rain and during those times may exchange water with the adjacent lagoon. The Lagoon site is located near the northern boundary of COPR where it borders a large restoration project, also affiliated with UCSB, the North Campus Open Space Restoration Project and Devereux Lagoon. The Lagoon site is in a transitional area between salt marsh and coastal prairie vegetation communities. The Pond and Lagoon COPR sites are owned by the UC Reserve System and are managed for their ecological value. The level of management varies by year depending on funding.

Figure 7. Reintroduction sites at Coal Oil Point Reserve and the North Campus Open Space.

4.2.1 Coal Oil Point Reserve Pond

The COPR Pond site lies in a flat area between established dunes and a freshwater pond. The Astragalus pycnostachyus var. lanosissimus planting area is periodically flooded when the pond overflows during periods of heavy rain. The margins of the pond are dominated by Schoenoplectus spp., Salix spp., and Typha sp.. Vegetation between the pond and the dunes is

characterized by a mix of coastal prairie, coastal sage scrub, dune vegetation, and non-native invasive plants. Common species include Baccharis pilularis, Artemisia californica, Polypogon monspeliensis (rabbit foot grass), Oenothera elata (evening primrose), Distichlis spicata, and Carex praegracilis (field sedge) (Meyer 2007, p. 48). Depth to ground water varies with annual precipitation. Vegetation composition at the COPR Pond site has shifted periodically since initial planting in 1999 in response to periods of inundation, drought, and average rainfall. The variable water table makes any plants present susceptible to periods of drought where in other locations they may be buffered by a more persistent water table. However, the resulting shifts in vegetation composition provide areas of bare or low vegetation cover that can provide opportunities for Astragalus pycnostachyus var. lanosissimus germination when other conditions are appropriate.

Plants of Astragalus pycnostachyus var. lanosissimus were first introduced to the COPR Pond site in 1999 at the request of an early recovery team that had formed following the rediscovery of the species (Sandoval 2002, p.1). Heavy rain during January 2001 caused 10 days of inundation at the Pond Site resulting in high mortality (Meyer 2007 p. 56). Following the flood event in 2001, additional plantings were installed. These plantings succeeded with supplemental watering, and over 6,000 seeds were collected from 16 plants representing and 12 maternal lines. The collected seeds were stored at the Santa Barbara Botanic Garden with a portion available to Rancho Santa Ana Botanic Garden for early viability and germination research (Sandoval 2002, p.1; Soza 2003, p. 17). In 2003, 200 seeds were added to experimental plots but germination and survivorship was low (Meyer 2007, pp. 31-32). An additional 40 plants were added to the Pond site in 2004, but flooding from February to March 2005, and again in 2006, limited survivorship. By the end of 2007, only five individuals survived (Meyer 2007, p. 57; Meyer 2012, p. 37). Plant numbers remained low until 2011 when 100 seedlings were observed. This was assumed to be caused by above average precipitation. Survivorship of the 2011 cohort decreased rapidly through 2012 and 2013. Six plants were planted in 2013 as part of a federal grant agreement with Rancho Santa Ana Botanic Garden. These plants did not survive, likely due to gopher (probably Thomomys bottae) herbivory (Meyer 2014, p. 1). An additional 21 plants were planted with gopher cages and an irrigation system in 2014. No data is available for the 2015 and 2016 seasons, but in 2017 and 2018 several small individuals with low vigor were observed. By August 2019 there were no surviving plants (Figure 8). There is likely an existing and viable seed bank from historical seed deposition, and it is possible that plants will naturally germinate at this location under favorable conditions in the future.

Figure 8. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Coal Oil Point Reserve Pond site. Total count is the last available count of individuals from a given year and includes flowering and non-flowering juveniles and adults when that information is available.

4.2.2 Coal Oil Point Reserve Lagoon

The Coal Oil Point Reserve Lagoon site was identified in 2003 as suitable for seeding trials and outplanting. The Lagoon site is located at a transitional elevation between salt marsh and coastal prairie and sage scrub. The salt marsh vegetation borders Devereux Lagoon, a seasonally sandbar enclosed lagoon. During the summer, or prolonged periods of drought, a sandbar is persistent at the mouth of the lagoon separating it from the Pacific Ocean. During the winter, freshwater input into the lagoon, waves, and a greater tidal range erode the sandbar, opening the lagoon to the Pacific Ocean and allowing mixing of lagoon and ocean water. During the periods when the lagoon is open to the ocean it is tidally influenced, but the effects of the tides are not present when the barrier is intact. The depth to water table has been measured at 84 cm (33 in.), 123 cm (48 in.), and a third measurement failed to reach ground water at 150 cm (59 in.) (Meyer 2007, p. 64). The water table is likely variable by season, dependent upon precipitation and tidal input when the barrier has been breached. As a result, the Lagoon site likely does not have a persistent perched water table but may frequently have a temporarily high water table primarily fed by freshwater input (Meyer 2007, p. 64). The area had been dominated by non-native species prior to 2002 but was partially restored by 2003 when Astragalus pycnostachyus var. lanosissimus seeding trials began. Removal of several Melaleuca sp. (bottlebrush) trees provided newly bare ground for outplanting in potentially suitable habitat. The border of the open area around the Lagoon site was characterized by Baccharis pilularis and Salix lasiolepis, and the open area was characterized by patchy Ambrosia psilostachya, Polypogon monspeliensis, Bromus spp., and Festuca myuros (formerly Vulpia myuros (rattail sixweeks grass)) (Meyer 2007, p. 48). Portions

of the Lagoon site at lower elevation near the lagoon contained salt marsh species such as Jaumea carnosa and Distichlis spicata.

Initial outplanting at the Lagoon site consisted of seeding plots in 2003. Approximately 200 seeds were added to a series of plots from the salt marsh margin through bare ground and into coastal prairie and sage scrub (Meyer 2012, p. 31). Approximately 20 percent of the seeds germinated by March 2003, although survivorship declined through the year with only 14 individuals surviving by November 2003. In 2004, 60 plants grown in containers were outplanted at the lagoon site. Initial survivorship was high but quickly declined with just 13 of the 60 plants surviving through the summer of 2006 (Meyer 2007, p. 28). Natural recruitment was very high in 2006 either from seed that was produced by outplanted individuals, or possibly ungerminated seed from 2003. Five hundred twenty four individuals were counted although the number surviving declined to one by 2010. Gopher bioturbation, herbivory from rabbits (possibly Sylvilagus bachmannii or S. audubonii) and voles (likely Microtus californicus), below average rainfall, and an increase in herbaceous species cover were thought to contribute to the decline in survivorship following the 2006 recruitment (Meyer 2012, pp. 34-35) (Figure 9). No plants were observed in 2011 and in 2012 and the cover of Leymus triticoides (alkali rye grass) and associated dense thatch have resulted in conditions no longer likely suitable for Astragalus pycnostachyus var. lanosissimus (Meyer 2012, p. 35). However, a seed bank likely persists and germination is possible if suitable conditions return.

Figure 9. Number planted and total count Astragalus pycnostachyus var. lanosissimus at the Coal Oil Point Reserve Lagoon site. Total count is the last available count of individuals from a

given year and includes flowering and non-flowering juveniles and adults when that information is available. No data was collected from 2013 to 2018.

4.3 NORTH CAMPUS OPEN SPACE RESTORATION SITE

The North Campus Open Space (NCOS) restoration site aims to restore estuarine and palustrine habitat, including wetlands and associated upland habitat, that had existed at the site prior to its conversion from natural land to a golf course. The NCOS restoration site surrounds the upper portion of Devereux Slough adjacent to the Coal Oil Point Reserve and is managed by UCSB. Restoration activities began in 2017 and cover 40 ha (100 ac). Restoration included grading, weed, thatch, and debris removal, installation of drip irrigation, planting. Monitoring of vegetation composition, wildlife, and water quality will track the progress of the site as it establishes.

Astragalus pycnostachyus var. lanosissimus was planted in a portion of the NCOS restoration site in October and November 2019 (CCBER 2019, p. 2). Approximately 229 plants were planted across a series of elevations in an area likely to be inundated during seasonally high rainfall events. Six additional plants were planted in an upland swale under a canopy of Salix lasiolepis. The smaller planting effort was opportunistic and will be used to aid in the determination of different environmental tolerances at the NCOS restoration site. The planting area is characterized by fine sand and occurs slightly beyond the high water mark of Devereux Slough (e.g. elevation 9.5 – 11 ft). Soil moisture, measured gravimetrically ranges from 15 to 30% and correlated to a volumetric soil moisture probe range of 20 to 50 % soil moisture (Stratton 2020, pers. com.). The estuarine conditions and tidal influence at the NCOS restoration site is very similar to the COPR Lagoon site which occurs in similar topographic conditions 200 m (656 ft) south in the same slough system. In December 2019, there was no associated vegetation interspersed between or surrounding the Astragalus pycnostachyus var. lanosissimus plantings which were planted on a series of low berms and swales created to evaluate small variations in topography and elevation. Salix spp. and Baccharis salicifolia will likely colonize from nearby plantings and salt marsh vegetation (Salicornia sp., Frankenia sp., and Distichlis spicata primarily) will colonize from the marsh edge with management. The plantings will be monitored monthly to evaluate survivorship, reproductive output, and threats (CCBER 2019, p. 6). During the 2019-2020 winter, the water table in Devereux Slough was high (8 – 9.5 ft) and the plants growing in the swales were inundated (low points between berms). Monitoring suggests that swale plants were doing more poorly than those on the berms. As of May 2020 there were approximately 203 new seedlings that had germinated from the few seeds dropped from the outplanted plants in November 2019 (Stratton 2020, pers. com.).

4.4 CARPINTERIA SALT MARSH RESERVE

The Carpinteria Salt Marsh Reserve (CSMR) is an estuarine system open to the Pacific Ocean and receiving freshwater input from Franklin and Santa Monica Creeks and overland runoff from surrounding infrastructure through a series of culverts. Both Franklin and Santa Monica Creeks are concrete lined until entering CSMR. Tidal channels and saltpans are interspersed with large sections of salt marsh characterized by Frankenia salina, Jaumea carnosa, Suaeda spp. (seablite), and Salicornia spp.. The higher elevation margins of the salt marsh contain shrubby

species such as Baccharis pilularis and Atriplex lentiformis. Escaped landscaping plants such as Amaryllis belladonna (naked lady) and Myoporum laetum (ngaio), along with weedy species such as Hirschfeldia incana (mustard), Brassica nigra (black mustard), Festuca perennis (rye grass), Polypogon monspeliensis, and Limonium duriusculum (European sea lavender) are common around upland margins and near an access road and railroad track. Salinity and soil moisture vary depending on the proximity to tidal channels. Outplanting locations for Astragalus pycnostachyus var. lanosissimus ranged in salinity from 6.15 mmhos/cm (low salinity) to 111 mmhos/cm (very high salinity), although the majority of planting areas averaged 28 mmhos/cm (moderate salinity). Soil moisture was also variable ranging from 8 percent to 25 percent (gravimetric) (Soza et al. 2003, pp. 9-13). Depth to ground water at the driest outplanting location was 112 cm (44 in) in 2004 and 99 cm (39 in) in 2006 (Meyer 2007, p. 63). Flooding of the outplanting locations has been observed infrequently during very high tides.

Astragalus pycnostachyus var. lanosissimus planting began in April 2002 at CSMR (Soza et al. 2003, p. 20). One hundred fifty-five plants were planted among five microsites located at the northeast corner CSMR on the southern side of a road berm in a transitional zone between salt marsh and upland/ruderal vegetation. Plants were hand watered periodically for the first six months and then left to natural precipitation. Sixty-four percent survived through November 2002, and by February 2003 survivorship dropped to 44 percent (Soza et al. 2003, pp. 45-51). Survivorship was highest at microsites where salinity was the lowest despite soil moisture being lower than the assumed minimum levels. In 2004, 40 additional plants were planted at the most successful locations at CSMR. Only 44 percent survived through summer 2006, many having succumbed to gopher bioturbation and rabbit herbivory (Meyer 2007, p. 28, 69, 80). Natural recruitment from seed produced by the 2002 and 2004 planting efforts was low until 2006 when 558 recruits were counted. Recruitment remained high until 2010 when survivorship and recruitment suddenly decreased (Meyer 2012, p. 27). Direct seeding of 300 seeds was done in 2011 but no germination from the seed was observed (Meyer 2012, p. 29). Gopher bioturbation and drought appeared to stress the plants, and an increase in weeds increased competition. Baccharis pilularis was also increasing in cover and was providing refugia for rabbits, leading to increased herbivory (Meyer 2012, pp. 28-29). By 2012 only a single plant remained (Figure 10). No data is available between 2013 and 2018, and the site appeared to no longer support suitable habitat for the species. An expansion of salt marsh species into the planting area suggests that salinity has increased (Meyer 2012, p. 29). However, in 2019 a single plant was observed growing up through an Artemisia californica shrub along the margin of the road berm on top of a culvert near the former outplanting locations (Callender 2019, NA).

Figure 10. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Carpinteria Salt Marsh Reserve. Total count is the last available count of individuals from a given year and includes flowering and non-flowering juveniles and adults when that information is available. No data was collected from 2013 to 2018. A single plant was observed in 2019.

4.5 MCGRATH STATE BEACH

McGrath State Beach begins at the Santa Clara River Mouth in Ventura County and runs south to the end of McGrath Lake, a back dune lake formed by a barrier dune that inhibits water from flowing to the ocean. McGrath Lake is fed by ground water and overland runoff from adjacent roads and agricultural fields. McGrath State Beach is bordered to the west by the Pacific Ocean and the east by Harbor Boulevard. The outplanting location at McGrath State Beach is located on the eastern margin of McGrath Lake near its midpoint. Habitat types are varied in the outplanting area consisting of wetlands along the margin of McGrath Lake, dune swales/mixed riparian in low lying ephemeral drainages, and coastal dune or scrub vegetation in the driest areas. Wetland vegetation is characterized by Schoenoplectus spp., Typha spp., Juncus spp., Distichlis spicata and Carex praegracilis. The dune swales and mixed riparian areas are characterized by Salix lasiolepis, Toxicodendron diversilobum (poison oak), Baccharis pilularis, Anemopsis californica, Oenothera elata and Baccharis salicifolia. Coastal dune and dune scrub vegetation is characterized by Abronia spp. (sand verbena), Ambrosia chamissonis (beach bur-sage), Ambrosia psilostachya, Calystegia soldanella (beach morning glory), Cakile maritima (sea rocket), Camissoniopsis cheiranthifolia (beach evening-primrose), Croton californicus (desert croton), Ericameria ericoides, Baccharis pilularis, and Artemisia californica. Common weeds include Carpobrotus spp., and Bromus spp.. Soil moisture varies across the outplanting site,

ranging from 1 percent to 17 percent (gravimetric) due to variation in topography and distance from McGrath Lake (Soza et al. 2003, pp. 13-15). Salinity similarly varied ranging from 0.43 mmhos/cm to 3.22 mmhos/cm, values indicating relatively low salinity. Depth to ground water has been measured at 42 cm, 53 cm, and 60 cm (1.38 ft, 1.74 ft, 1.85 ft respectively). The relatively shallow groundwater is attributed to a dense clay layer beneath the predominantly well drained sandy soils (Meyer 2007, pp. 61-63). The outplanting locations are located within an area that floods during periods of high precipitation when McGrath Lake may overflow its normal high water mark (Meyer 2007, p. 57).

One hundred sixty seven plants were installed across five areas at the McGrath State Beach outplanting site in 2002 (Soza et al. 2003, p. 20). Plants were initially watered once per week but decreased to once per month by the 6th month following planting and was ceased with the onset of fall rains (Soza et al. 2003, p. 21). By February 2003, survivorship was high, ranging between 79 percent and 97 percent across the planting areas (Soza et al. 2003, p. 50). Recruitment from seed produced by the first year plantings was also observed in 2003. Survivorship rapidly decreased in 2004, likely due to herbivory, but recruitment remained relatively high. In 2005, flooding throughout the planting area resulted high mortality of the remaining 2002 plants. However, the flooding also redistributed seed and germination was extremely high following the recession of flood water. Recruits were found in areas not previously planted although not all recruits survived when they germinated in areas of high shade, competition, or herbivory (Meyer 2007, pp. 101-103). Of the original 2002 plants, only three produced new stems in spring 2006 and none survived through 2007 (Meyer 2007, pp. 69-70). Recruitment and survivorship was low in 2006 and the number of plants at McGrath State Beach declined to five by 2012 (Figure 11). The expansion of Salix lasiolepis, Salix exigua, Baccharis pilularis, and proximity of planting areas to refugia for herbivores have likely decreased the suitability of these areas for Astragalus pycnostachyus var. lanosissimus (Meyer 2012, pp. 21-26). It is likely that a seed bank persists and future recruitment is possible if conditions become more favorable. No data were collected between 2013 and 2018. In 2019, surveys by the Service found no plants throughout summer and early fall (Lemein and Niessen 2019, pers. obs.).

Figure 11. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the McGrath State Beach site. Total count is the last available count of individuals from a given year and includes flowering and non-flowering juveniles and adults when that information is available. No data was collected from 2013 to 2018. No plants were observed in 2019.

4.6 MCGRATH PARCEL

The McGrath Parcel is an outplanting location east of McGrath Lake and just south of the McGrath State Beach outplanting site on land owned by the City of Oxnard. The outplanting is required by permit condition for the development at the North Shore site and is managed by Arcadis (Arcadis 2019a, p. 1-1). The McGrath Parcel also serves as a wetland mitigation area for impacts to wetlands regulated under the Coastal Act (Arcadis 2019b, p. 7). Wetland mitigation (contouring, planting, and weeding) began in 2008 and was complete in 2019 (Arcadis 2019a, pp. 1-4). Portions of the wetland mitigation area were chosen for outplanting of Astragalus pycnostachyus var. lanosissimus in 2016. The outplantings will be maintained for 10 years with regular monitoring, weeding, and supplemental irrigation (Arcadis 2019a, p. 1-1).

Historically, the McGrath Parcel had been farmed, used for oil drilling, production, and storage, and was also the site of a go-kart track. Currently, the McGrath Parcel serves as a wetland mitigation area for the North Shore development, an outplanting location for Astragalus pycnostachyus var. lanosissimus, and also has an active oil lease within the parcel. The McGrath Parcel is contiguous with the southern border of McGrath State Beach, and habitats between the two parcels are similar, consisting of coastal dune scrub, coastal sage scrub, willow scrub, and wetlands (Arcadis 2019a, p. 1-2). Soil moisture at 45 cm (18 in) varies from 16 percent to 90 percent (capacitance) throughout the site and changes based on the amount of precipitation and time of year (Arcadis 2019a, Figures 6a-6c).

Two hundred twenty seven individuals of Astragalus pycnostachyus var. lanosissimus were planted at the McGrath Parcel in 2016. Heavy rains resulted in flooding and mortality of plants in the flooded areas. In November 2016, 156 plants were still alive. An additional 101 plants were planted in 2017. In contrast to 2016, plants in 2017 were stressed from lack of moisture and those in the most dry locations had the highest mortality. By the end of 2017, 211 plants were still alive. One hundred plants were alive in May 2018 but survivorship decreased each month until only 55 remained in October 2018. Natural recruitment was observed in 2018 but most seedlings did not survive the summer months (Arcadis 2019a, p. 3-9). In 2019, 474 individuals were present by the end of the year, including 80 seedlings and juveniles. As of July 2020, 282 adults and 72 seedlings and juveniles are present at the McGrath parcel (Carroll 2020, pers. com.).

4.7 MANDALAY STATE BEACH

The outplanting site at Mandalay State Beach is in restored back dunes, swales, and willow thickets at the south end of Mandalay State Beach and north of West 5th Street. The property is owned by the California Department of Parks and Recreation. The North Shore site, where the species was rediscovered, is approximately 0.25 mi east of the Mandalay State Beach site but is separated from the site by Harbor Boulevard and graded housing pads and roads for residential development. The outplanting site is characterized by patches of bare ground, sparse to dense stands of Baccharis pilularis, a dense stand of Salix lasiolepis bordering the northern portion of the outplanting, and mats of Distichlis spicata, and Juncus sp. (Wilken and Wardlaw 2001, p. 17). Soil saturation (measured as the amount of water needed to saturate a 100 gram sample) was 36 percent and salinity was 0.8 mmhos/cm at the only sampled location within the outplanting area (Wilken and Wardlaw 2001, p. 8, 42). Depth to ground water was measured between 121 cm (48 in) to 128 cm (50 in) in January 2004 at three locations (Meyer 2007, p. 61).

Fifty plants were outplanted across three sites at Mandalay State Beach in February 2003. Two of these planting areas were in a northern section of the outplanting area in shallow dune swales with low vegetative cover. These areas were too dry and plants did not survive the summer. In 2004, 35 additional plants were added to the initial outplanting area. Survivorship of the 2003 and 2004 plants declined annually. Herbivory, dry soil, and expanding Salix lasiolepis thickets as well as an increase in herbaceous mat forming species such as Juncus sp. and Distichlis spicata, contributed to the decline in survivorship and habitat suitability (Meyer 2012, pp. 17-21). Natural recruitment was observed in 2005 but survivorship was low. Recruitment and survivorship declined through 2012 when only two individuals remained (Figure 12). No information is available from 2013 through 2018 but surveys by the Service in 2019 found no individuals throughout the outplanting area (Lemein and Niessen 2019, pers. obs.).

Figure 12. Number planted and total count of Astragalus pycnostachyus var. lanosissimus at the Mandalay State Beach site. Total count is the last available count of individuals from a given year and includes flowering and non-flowering juveniles and adults when that information is available. No data was collected from 2013 to 2018. No plants were observed in 2019.

4.8 ORMOND BEACH

The Ormond Beach outplanting site was identified in 2004 and is located on land owned by the California Coastal Conservancy and managed by The Nature Conservancy. The parcel is part of several that are being incorporated into a large restoration project being planned by the California Coastal Conservancy, The Nature Conservancy, and the City of Oxnard (ESA 2019, entire). The outplanting site was located in an area characterized by predominantly salt marsh vegetation including Jaumea carnosa, Juncus acutus (spiny rush), Distichlis spicata with large areas of unvegetated salt pans. In transitional areas between salt marsh and uplands, Ambrosia psilostachya was dominant (Meyer 2007, p. 37). The habitat is comparable to the habitat evaluated by Wilken and Wardlaw (2001, entire) at Naval Base Ventura County, which borders the Ormond outplanting location. The habitat also resembles habitat found in the more saline conditions at the Carpinteria Salt Marsh Reserve. The depth to the water table is between 43 cm (17 in) and 137 cm (54 in) and is supported by a clay layer that inhibits draining although variability based on season has been observed (Meyer 2007, pp. 59-60). Data on salinity and soil moisture is not available for this site, but the dominant vegetation suggests salinity is too high to support Astragalus pycnostachyus var. lanosissimus.

Forty plants were outplanted at the Ormond Beach site in 2004. Approximately one-third failed due to herbivory from rabbits within one week (Jensen 2007, p. 17). Most of the remaining plants died, likely due to high salinity. The plants that survived through 2004 did not survive an

inundation event in 2005. No plants were noted to have flowered and the resulting lack of a seed bank led to no natural recruitment following the inundation event (Jensen 2007, p.17). The habitat at this site does not appear suitable for Astragalus pycnostachyus var. lanosissimus.

5 CURRENT DISTRIBUTION, ABUNDANCE, AND MANAGEMENT

We consider there to be six extant potential populations of Astragalus pycnostachyus var. lanosissimus. We only consider populations that currently have, or are likely to have, suitable habitat and a viable seedbank as extant. Reintroduction sites where habitat was found to not be suitable and where a seed bank is unlikely to persist, or where germination potential and survival is low, are considered extirpated and not considered further. With this definition, the North Shore site, Coal Oil Point Reserve (COPR) Pond, North Campus Open Space (NCOS) restoration site, Carpinteria Salt Marsh Reserve, McGrath State Beach, and McGrath Parcel all contain extant populations. While the COPR Pond and NCOS restoration site, and the McGrath State Beach and McGrath Parcel populations are geographically close pairs, each of the pair is hydrologically separated based on topography and/or the source of the water table. Additionally, these sites have distinct current and historical management practices that further justify their consideration as separate populations.

The COPR Lagoon, Mandalay State Beach, and Ormond site all failed relatively rapidly, suggesting that those sites are not suitable for the species. The COPR Lagoon transitioned from suitable habitat to salt marsh and dense upland non-native grasses following the initial removal of invasive species, and is not likely suitable for the species either due to salinity or competition from non-native species. Mandalay State Beach is likely too dry with a water table that is too deep to support Astragalus pycnostachyus var. lanosissimus in areas where interspecific competition is light enough to allow survival. The Ormond site is likely too saline, as evidenced by the dominance of salt marsh vegetation and barren salt pans. The COPR Lagoon, Mandalay State Beach, and Ormond reintroduction sites no longer have suitable habitat, are not likely to in the future, and seed that may be present is unlikely to germinate and survive until reproduction.

5.1 NORTH SHORE

In 2009 the Ventura marsh milk vetch preserve (VMMVP) was recorded in a conservation easement held by the City of Oxnard with California Department of Fish and Game (now California Department of Fish and Wildlife) as a third party beneficiary (City of Oxnard 2009, entire). The VMMVP covers 1.66 ac (0.67 ha) and contains the entirety of the Astragalus pycnostachyus var. lanosissimus occurrence at the North Shore site. The VMMVP is surrounded by a buffer area that is included in a separate conservation easement designated to support coastal dune, dune scrub, and sage scrub vegetation. Active management including monitoring, irrigation, and weeding, and occurs throughout the year to ensure that the species does not become extinct at the North Shore site (Arcadis 2018b, Appendix C p. 3-2). Annual monitoring includes a census of the population and data collected on number of stems, length of stems, presence and quantity of basal shoots, notes on herbivory, pathogens, or other threats, and reproductive output (Arcadis 2018b, Appendix C pp. 3-2 – 3-3).

A mix of riparian, scrub, and dune species including Salix lasiolepis, Artemisia californica, Baccharis pilularis, Baccharis salicifolia, Malosma laurina (laurel sumac),, Cryptantha

34 intermedia (common cryptantha), Descurainia pinnata (tansy mustard), Erigeron canadensis (horseweed), and Crassula connata (pygmy weed) and characterize the vegetation near colonies of Astragalus pycnostachyus var. lanosissimus in the VMMVP, with additional species such as Ericameria ericoides, Ambrosia chamissonis, Camissoniopsis cheiranthifolia, Croton californicus, and Heterotheca grandiflora (telegraph weed) in well-drained sandy soils nearby (Arcadis 2018b, Appendix D, Table D1). Myoporum laetum, Carpobrotus edulis, Cortaderia jubata (jubata grass), Foeniculum vulgare (fennel), and Oxalis pes-caprae (Bermuda buttercup) were common prior to weed management and are now absent from the site. The soil is primarily sand mixed with silt, clay, and organic detritus. Unremediated oil waste (“sludge”) lies beneath the VMMVP and is believed to have helped form the perched water table at the site. Soil samples collected in 1997 and 2009 indicate that the depth to oil-affected soil where Astragalus pycnostachyus var. lanosissimus occurs ranges from 0.2 m (0.66 ft.) to 1.1 m (3.75 ft.) below the soil surface. Excavation of the root zone of a single plant in 1997 found that roots were restricted to soils above the oiled layer and that roots within the oiled layer were necrotic (Arcadis 2017, Appendix F, Appendix B, p. 1)

There were 372 plants when the population was discovered in 1997 including 112 adults and 260 seedlings and juveniles. Between 1997 and 2006 the number varied around a mean of 230 plants with adults ranging from a low of 9 in 2001 to a high of 159 in 2004. A period of below average rainfall in 2006, potentially exacerbated by changes to the site hydrology caused by remediation activities around the preserve, led to a decrease in the number of plants surviving. In 2009 only 27 plants, persisted and soil moisture monitoring and irrigation lines were installed. The number of plants began to rebound in following years, reaching a high of 264 in 2017 before declining to 198 plants in 2018 (Arcadis 2018a, NA). By the end of 2019, 180 adults were alive, and as of July 2020, 457 individuals are present, including 139 adults and 318 seedlings and juveniles (Figure 13).

Figure 13. Total count of adult and juvenile Astragalus pycnostachyus var. lanosissimus at the North Shore site (solid line) and total number of adults (dotted line).

5.2 MCGRATH PARCEL

The McGrath Parcel is managed similar to the North Shore site and is under similar regulatory framework. Weeding, native species control, irrigation, and soil moisture monitoring occur monthly and this is expected to continue through 2025 when the permit requirements expire. Supplemental planting occurred throughout 2016 and 2017 and it is possible for additional plants to be planted as needed in the future. In November 2019, 394 plants and 80 seedlings were observed at the McGrath Parcel. As of July 2020, 282 adults and 72 seedlings and juveniles were present at the McGrath parcel. This includes planted individuals as well as naturally recruited individuals.

5.3 CARPINTERIA SALT MARSH

There has been no management of the Carpinteria Salt Marsh outplanting site since 2012. Initial plantings in 2002 and seeding were at first successful, but survivorship declined rapidly beginning in 2010. The outplanting area is now dominated by weeds (Bromus spp., Hirschfeldia spp.) and upland shrubs (Baccharis pilularis, Artemisia californica). Halophytes, previously absent from the outplanting area, are now encroaching upon it suggesting that salinity may be increasing in the soil (Meyer 2012, p. 29). Astragalus pycnostachyus var. lanosissimus was believed to be extirpated from the site until a single individual was identified during avian surveys in summer 2019 (Callender 2019, NA). The single plant was found growing through an Artemisia californica shrub on a road margin above a culvert near the original planting area. The emergence of a single individual after years of no management suggests a persistent and viable seed bank exists at the Carpinteria Salt Marsh. Changes in the vegetation community towards a dominance of halophytes or upland shrubs suggest declining suitability for establishment. This site may remain suitable depending on the evolution of microsite characteristics.

5.4 COAL OIL POINT POND

There are currently no individuals of Astragalus pycnostachyus var. lanosissimus at the Coal Oil Point Reserve (COPR) Pond site. Two individuals were alive in August 2018 but appeared stressed and did not survive into 2019. The plant community shifts rapidly depending on the rainfall year and whether or not flooding has occurred at the COPR Pond site. In 2019 the plant community was dominated by Oenothera sp., Polypogon monspeliensis, and Baccharis pilularis. The periodic flooding, shifts in vegetation community, and likely persistent seed bank suggest that this site is still viable in years when conditions would favor establishment of Astragalus pycnostachyus var. lanosissimus.

5.5 NORTH CAMPUS OPEN SPACE RESTORATION SITE

Two hundred twenty nine individuals were planted at the North Campus Open Space (NCOS) restoration site between October and November 2019. The plants were transplanted from two- gallon containers and 15 percent were already reproductive with flowers and seed bearing fruit. Currently, the plants exist on a barren flat at an intermediate elevation between the slough and

salt marsh vegetation and the planted upland grassland. Associated plantings and natural recruitment of native species are anticipated. Staff at UCSB will monitor the plantings monthly and additional plantings may occur in the future.

5.6 MCGRATH STATE BEACH

There are currently no reproductive adults at McGrath State Beach, but the seed bank is presumed to be viable and there is suitable habitat present where seed may be deposited during flood events. The primary driver of flooding at McGrath State Beach is the overtopping of the banks of McGrath Lake due to sustained precipitation. Flooding has occurred periodically in the past and germination of Astragalus pycnostachyus var. lanosissimus has followed periods of inundation. There is currently no management of this area, but potential for weed management and monitoring.

6 THREATS AND FACTORS INFLUENCING VIABILITY

At time of listing in 2001, the primary threat to Astragalus pycnostachyus var. lanosissimus was the direct loss of the sole population due to soil remediation and residential development (Service 2001, 50 CFR Part 17 RIN 1018-AF61). Additional threats included anthropogenic and natural stochastic events that could result in the elimination of the sole natural population, changes to hydrology, competition with native and non-native plants, herbivory, disease, and seed predation. Since listing, herbivory has proven to be a more substantial threat than initially believed (Service 2010, p. 14). Climate change, specifically changes in precipitation patterns (amount and timing), changes in seasonal temperatures, and shifts in vegetation communities, along with sea level rise have also been identified has threats to Astragalus pycnostachyus var. lanosissimus (Service 2010, pp. 17-18).

6.1 SOIL REMEDIATION AND RESIDENTIAL DEVELOPMENT

The threats from soil remediation and residential development are only at the North Shore site. At the time of rediscovery, soil remediation and residential development were going to remove individuals and habitat of Astragalus pycnostachyus var. lanosissimus. This was avoided through a Memorandum of Understanding between the developer and the California Department of Fish and Wildlife (formerly the California Department of Fish and Game) that established the VMMVP and buffer area. The Coal Oil Point Reserve (COPR) Pond site, COPR Lagoon site, North Campus Open Space (NCOS), Carpinteria Salt Marsh Reserve, McGrath State Beach, McGrath Parcel, Mandalay State Beach, and Ormond Beach are all located on land that is being managed for ecological value and are not subject to further development.

Soil remediation activities have concluded, but may have resulted in the alteration of local hydrology and permanently altered the water table at the North Shore site (Service 2010 pp. 12- 13). Soil moisture monitoring wells and an irrigation system were installed in 2009 and have provided necessary supplemental water when soil moisture naturally becomes too low for plant survival. Further negative effects from the soil remediation activities are not anticipated.

Direct loss of plants and habitat from the planned residential development has been avoided by the establishment of the VMMVP and surrounding buffer area, along with an agreement to

maintain the population in perpetuity. Indirect effects from the residential development are still possible and may include further changes in site hydrology, the need for fire fuel load reduction in residential areas, herbicide drift, and trespass.

6.2 ANTHROPOGENIC AND NATURAL STOCHASTIC EVENTS

Anthropogenic and natural stochastic events are random events that have the capability of causing extirpation of populations with small numbers of individuals and/or limited spatial extent. At the time of listing there was a single population with 350 individuals and little was known about the biological needs and life history of the species. Potential anthropogenic and natural stochastic events include vehicular trespass or vandalism, environmental conditions at time of seed germination, and the timing of floods. Since listing, stochastic events have seemingly played a significant role in the difficulty of establishing populations at sites other than the North Shore site. Periodic floods have resulted in high mortality just following outplanting, and vandalism at the North Shore site has resulted in periods where supplemental water could not be provided. The failure of nearly all outplanting areas to establish increases the significance of the threat of stochastic events to the remaining populations, although this threat is lessened at the North Shore site and McGrath Parcel where active management is occurring and rapid responses to unforeseen events are possible.

6.3 ALTERATION OF HYDROLOGY

A perched water table that allows high soil moisture at 45 cm (18 in) below ground and dry soils at the surface has been identified as a key biological need of Astragalus pycnostachyus var. lanosissimus. At the North Shore site this was believed to have been maintained by an oil layer that acted as a barrier to water draining through the soil column. Changes in the surrounding landform (grading, soil dumping, and compaction) likely changed the flow of water through the North Shore site resulting in a decrease of water available to perch above the oil layer. This was mitigated in 2009 by the installation of a soil moisture monitoring system and an irrigation system. The planned residential development may have further effects on the local hydrology at the North Shore site if further grading and compaction is required as part of construction.

Each of the outplanting sites were chosen for their perceived suitability including the presence of a water table near the surface. The outplanting sites are all located in close proximity to the ocean and/or bodies of freshwater that can support a high water table. At these sites, increased ground water from sea level rise or loss of freshwater inputs are likely the greatest threat to the hydrology. An increase in ocean-derived groundwater would increase soil salinity resulting in a decrease in the suitability of the area for Astragalus pycnostachyus var. lanosissimus. At the Coal Oil Point Reserve (COPR) Pond, McGrath State Beach, and McGrath Parcel sites, a loss of freshwater input to McGrath Lake and the COPR Pond may lower the water table resulting in soils too dry or too saline to be suitable for Astragalus pycnostachyus var. lanosissimus. Because each of the outplanting sites are located in areas that are protected from development, the likelihood of either happening are dependent upon climate change and/or sea level rise rather than land use. No hydrologic modeling has been performed that would allow an evaluation of the probability of either occurring.

6.4 COMPETITION WITH NATIVE AND NON-NATIVE PLANTS

Observations from the North Shore site and the outplanting sites suggest that Astragalus pycnostachyus var. lanosissimus is a poor competitor for resources both from non-native and native plants. At the North Shore site and all outplanting sites, aggressive removal of non-native invasive species resulted in increases in survivorship and recruitment. Weed management is currently required by regulatory guidance at the North Shore site and McGrath Parcel. Weed management is also ongoing at the North Campus Open Space (NCOS) to promote establishment of the recent outplantings and surrounding restoration of habitat. The remaining outplanting sites are no longer managed for weeds and the increase in non-native species has contributed to the decline and/or lack of success of permanent establishment at those sites. Our current understanding of the life history of Astragalus pycnostachyus var. lanosissimus is that it colonizes newly disturbed areas following floods. This puts the species in direct competition with fast growing non-native plants with high reproductive output. At all sites Astragalus pycnostachyus var. lanosissimus is not likely to persist in competition with non-native plants without active management. Similarly, the species is not a good competitor with later- successional native species. Between disturbances, habitat will shift from early successional species (including Astragalus pycnostachyus var. lanosissimus) towards later successional species such as Salix spp., Baccharis pilularis, Artemisia californica, or other shrubs characteristic of riparian or coastal sage scrub habitat types. As shrub species increase in cover the success of Astragalus pycnostachyus var. lanosissimus declines. Astragalus pycnostachyus var. lanosissimus may be similarly outcompeted by rhizomatous herbaceous species (e.g. Juncus spp., Carex spp.) that can form dense mats and compete for space and resources similarly to shrub species. Threats from both non-native and native species are present at all sites and are likely to continue to be threats in the future.

6.5 HERBIVORY

Herbivory has been observed at the North Shore site and all outplanting sites. The dominant herbivores are snails, rabbits, gophers, and voles. Two types of snails have been tentatively identified, milk snails (Otala lactea) and common brown garden snails (Cornu aspersum) (Meyer 2007, p. 119), both which are non-native. Snails have been observed eating new shoots, leaflets, buds, inflorescences, and stems. When snail herbivory is severe, it may result in defoliation, stem senescence, and reduction of reproductive output. Snail herbivory is exacerbated by the presence of dense herbaceous vegetation and mats of Carpobrotus edulis that provide moist refugia for the snails between periods of foraging. Snail herbivory may be reduced through weed management, thereby decreasing refugia for snails, and through the use of snail bait and hand removal (Meyer 2007, pp. 119-121).

Rabbits, gophers, and voles each pose threats to the establishment and persistence of Astragalus pycnostachyus var. lanosissimus. Rabbits have had the greatest negative effect on the establishment of outplanting locations with herbivory taking the form of removal of seedlings, cropping of new shoots from the root crown, and consumption of new stems and leaflets on mature plants. Often herbivory on mature plants results in mortality. Rabbit herbivory increases with decreasing distance to shrubs and/or small trees that provide cover from predators. Gophers are most common in drier areas, presumably because frequent flooding of their tunnels is not tolerated. Gophers may directly consume Astragalus pycnostachyus var. lanosissimus and may

also chew through protective caging that is installed around plantings to prevent herbivory. Gopher herbivory has been most prevalent at the Carpinteria Salt Marsh Reserve and has not been observed at the North Shore site (Meyer 2007, pp. 122-123). Voles are most common in areas where there is high herbaceous cover and have been most frequently observed at the McGrath State Beach and Coal Oil Point Reserve Lagoon sites. Signs of vole herbivory include cleared paths through herbaceous vegetation that lead to the bases of Astragalus pycnostachyus var. lanosissimus.

Given the variation in herbivores, there is likely to always be a threat from at least one taxon on a population of Astragalus pycnostachyus var. lanosissimus. Herbivory may be reduced through baiting and hand removal (snails), caging (rabbits, gophers, voles), or removal of non-native plants and reduction of shrub and tree cover (snails, rabbits, gophers, voles).

6.6 DISEASE

At time of listing a sooty fungus associated with aphid secretions had been observed on Astragalus pycnostachyus var. lanosissimus at the North Shore site (Service 2010, p. 13). The sooty fungus and aphids appear in the more humid conditions that have been associated with tree tubes used in outplanting (Meyer 2007, p. 117-118). Despite the occasional presence of sooty fungus and aphids, it does not appear to be a significant cause of mortality or loss of reproductive output.

Recently, powdery mildew has been observed on plants at the North Campus Open Space (NCOS). The source for the spread of powdery mildew could be the presence of associated weedy species such as Melilotus spp. that are susceptible to powdery mildew and were present in high numbers prior to outplanting and maintenance at the NCOS site (Stratton 2020, pers. com.). No mortality resulting from the presence of powdery mildew has been observed at NCOS.

6.7 SEED PREDATION

Seed beetles (Family Bruchidae) have been observed on fruits and seeds at the North Shore site and outplanting sites since the rediscovery of Astragalus pycnostachyus var. lanosissimus in 1997. The effect of seed beetles has been variable. In 1997 seed production was estimated to be reduced by 44 percent as a result of seed beetle damage. In 2000, 30 percent of all seeds were estimated to be damaged by seed beetles at the North Shore site (Meyer 2007, p. 138). In 2003 and 2004, estimates of seed beetle damage were much lower: less than one percent in 2003 and two percent in 2004 at the McGrath State Beach and Mandalay State Beach sites. More recent data on seed beetle damage is not available. However, even when seed beetle damage is high (greater than 30 percent), about two viable seeds are produced per fruit. Wilken and Wardlaw (2001, p. 11) found that the average plant produced 26 inflorescences and each inflorescence averaged 37 flowers. If we assume a 50 percent pollination rate leading to successful fruit production, the average mature plant would produce 962 seeds when beetle damage occurs as described ( ½ (26 inflorescences/plant * 37 flowers/inflorescence * 2 seeds/damaged fruit)) resulting in very high seed output for an average healthy plant. Seed predation by seed beetles is not likely to be a limiting factor in the persistence of Astragalus pycnostachyus var. lanosissimus at the North Shore site, or in the establishment and persistence of the species at outplanting sites.

6.8 CLIMATE

Annual precipitation patterns are similar across the current geographic distribution of Astragalus pycnostachyus var. lanosissimus, with Ventura (Oxnard) slightly drier than Carpinteria, which is slightly drier than Goleta (Figure 14). Periods of above average rainfall are often followed by periods of drought. An extended period of below average precipitation occurred from 2012 through 2016, coinciding with a decline in all outplanted populations of Astragalus pycnostachyus var. lanosissimus. The average rainfall varies from 36 cm (14.2 in) to 44 cm (17.3 in) between Ventura (measured at the Ventura Harbor, VCWPD Station 216B/C 2019) and Goleta (measured at University of California Santa Barbara, SBCFCD Station 208 2019). The observed precipitation totals suggest declining total rainfall since the rediscovery of Astragalus pycnostachyus var. lanosissimus in 1997.

Figure 14. Total precipitation by water year (Oct-Sept). Total precipitation measured at the Ventura Harbor (Ventura), Carpinteria Fire Station (Carpinteria), and UCSB (Goleta) are shown from 1997 through 2018. The two horizontal lines represent historical average rainfall for Ventura (lower average) and Goleta (higher average).

Precipitation affects the immediate soil water availability, depth to the water table, flood events, and germination. High rainfall years may be either beneficial or detrimental to Astragalus pycnostachyus var. lanosissimus, while low rainfall years are never beneficial. High rainfall years are likely to lead to periods of flooding that are likely to result in mortality of inundated populations of Astragalus pycnostachyus var. lanosissimus while also redistributing seed and providing enough moisture for germination of seedlings in newly disturbed and/or suitable areas. The persistence of new seedlings is likely dependent on the persistence of the water table which may be determined by the amount and timing of subsequent precipitation events. Low rainfall years are likely to decrease the water table leading to increased water stress and increased mortality where adequate moisture is not present.

6.9 FACTORS INFLUENCING VIABILITY

There are many factors that influence the viability of a population of Astragalus pycnostachyus var. lanosissimus, and the interactions among all those factors are more numerous than can be usefully considered in this document. Figure 15 shows key factors and positive and negative interactions that influence the resiliency of a population based on the species demography (Section 2), biological needs (Section 3, Table 2), threats (Section 6), and management actions (Sections 8 and 9).

Figure 15. Influence diagram for Astragalus pycnostachyus var. lanosissimus population resiliency. Red boxes represent threats, orange boxes represent habitat needs, and green boxes represent life stages. White boxes illustrate where human actions can influence the population resiliency pathway. Arrows indicate the direction of an interaction. Red lines indicate negative interactions and green lines indicate positive interactions. Black lines represent natural processes. All interactions end with an arrow.

The diagram reflects the complex interactions between management actions, threats, and habitat needs that may result in competing positive and negative influences within the life cycle of Astragalus pycnostachyus var. lanosissimus. Because the species is a short-lived perennial, the overall resiliency of a population is based both on the current habitat conditions as well as the potential for suitable conditions to be created in the future. The suitability of habitat is cyclic based on the dynamic environment. It is possible that where there are no adult plants there is still a seed bank that allows for the population to persist though periods unfavorable to germination and survival of adult plants. For this reason, it is difficult to describe a population as extirpated when potentially suitable habitat is present and a seed bank is presumed to exist. Threats may negatively affect both habitat needs as well as seedlings and reproductive adults. The management actions we consider may reduce the impact of threats to individual habitat needs or directly aid in resiliency through reintroduction of plants to populations.

7 CURRENT CONDITION (RESILIENCY, REPRESENTATION, REDUNDANCY)

The current condition of the species is evaluated in relation to resiliency, representation, and redundancy. Resiliency is the ability of individual populations to withstand stochastic disturbance. Populations that are large and have high growth rates have greater resiliency. Representation describes the ability of a species to adapt to changing environmental conditions through the breadth of genetic and environmental diversity within and between populations.

Redundancy refers to the ability of a species to withstand catastrophic events and is measured by the number and distribution of populations.

7.1 RESILIENCY

Seven factors were evaluated to characterize the resiliency of Astragalus pycnostachyus var. lanosissimus populations: dynamic environment, vegetation cover, associated species, water table, soil moisture at 18 inches, reproductive adults, and seed bank (Table 2). Two of these measures, dynamic environment and proximity to ground water, are site dependent and difficult to manage for or to restore if absent from a site. For example, since flooding is the primary disturbance agent, disturbance is not easily introduced or managed within the urban/natural interface where the species currently exists. Man-made disturbances (e.g. disking, mowing, hand clearing of existing vegetation) may be suitable but have not been evaluated. Similarly, proximity to ground water is not easily managed and instead supplemental watering may be used where the groundwater supply is not adequate. The remaining five measures are more easily managed. Vegetation cover, associated species, soil moisture and substrate, reproductive plants, and seed bank may all be supported by management actions such as supplemental planting, weeding of undesirable species, soil monitoring, irrigation, and introduction of seed.

Resiliency was evaluated by scoring each of the seven factors (see Table 2, Section 3.2.2 for description) as low (0, red), moderate (1, yellow), or high (2, green). The mean of the score across all seven factors was then used as a measure of the overall resiliency of the population with scores from 0 – 0.66 ranked as low, 0.67 – 1.33 as moderate, and 1.34 and above as high. A low resiliency score suggests a population in decline due to unsuitable habitat conditions and at risk of extirpation due to declining habitat conditions and/or susceptibility to stochastic events. Populations with moderate resiliency scores have some habitat conditions that are not suitable for the species but enough that are suitable to allow the persistence of plants or germination of seed. Further loss of suitable habitat conditions may make the population less resilient. A high resiliency score indicates a population that has suitable habitat conditions, reproductive adults, and germinating seed. We recognize that our categories allow for a population with only 100 individuals to be considered to have high resiliency and that this is lower than many published minimum viable population sizes (Traill et al. 2007, entire; Flather et al. 2011, entire; Jamieson and Allendorf 2012, entire). It’s important to note, however, that the 100 individuals does not include the seed bank. Populations of Astragalus pycnostachyus var. lanosissimus are also likely to be limited by the lack of available potential habitat. Additionally, we believe that a decline to zero adult individuals (the population exists as a seed bank) is likely in naturally functioning habitats with successional vegetation dynamics, but that active management can increase the likelihood of persistence for a given population size.

Our evaluation of the North Campus Open Space (NCOS) restoration site is based on what currently exists at the site and takes into consideration the level of management that will be directed towards establishing the population. Information regarding the level of disturbance from seasonal flooding, seasonal variations in the water table, soil moisture, and species composition will be collected in subsequent years providing a better understanding of the site characteristics and the species tolerances. The current evaluation of the resiliency of the NCOS restoration site should be considered an estimate (est).

Of the six extant populations of Astragalus pycnostachyus var. lanosissimus, two were found to have high resiliency, two had moderate resiliency, and two are considered to have low resiliency (Table 3).

Table 3. Resiliency (2019) of the potentially extant populations. The North Shore site and all reintroduction sites were categorized as low, moderate, and high (0, 1, 2 respectively) for each population need. The average (mean) category value was then used to provide an overall score. Populations that scored 0 to 0.66 had low resiliency. Populations were considered moderately resilient if scored between 0.67 and 1.33. Populations with high resilience were those that scored greater than 1.33. The North Campus Open Space restoration site is still in development and the evaluation of that site is based on estimates (est).

at 18 inches

Site Dynamic Environment Vegetation Cover Species Associated Water table moisture Soil Reproductive adults Seed bank Overall

North Shore 1.43

Coal Oil Point Reserve Pond 1.00

North Campus Open Space est est est est est est est 0.86

Carpinteria Salt Marsh Reserve 0.57

McGrath State Beach 0.57

McGrath Parcel 1.86

The North Shore site was found to have high resiliency based on the seven factors. The site exhibited the greatest resiliency between 1997 and 2009, the period during which no supplemental watering or subsurface water moisture monitoring was conducted. During this period there were fluctuations in the number of individuals based on annual environmental conditions. This ended when the population declined rapidly due to drought and/or peripheral soil remediation activities that changed the hydrology and affected the water table. The population at the North Shore site is now conservation reliant, depending on supplemental

watering and weed management in order to persist. As a result, this population is not likely to become extirpated, but it is no longer functioning as a natural population.

The McGrath Parcel population also has high resiliency. The site is in a similar circumstance as the North Shore population. While plants are doing well at the site, it is likely due to supplemental planting, soil moisture monitoring, supplemental irrigation, and the weed management program. It is likely that if all management were removed from the McGrath Parcel and North Shore populations the resiliency of the populations would decline.

The COPR Pond was found to have moderate resiliency and has had variable success since establishment in 1999. Management has been generally limited to outplanting with little weed control or supplemental watering. There has been less than 10 to no individuals since 2015 although habitat conditions are moderate to high which is supporting the moderate resiliency score. If habitat conditions decline the resiliency of this population will fall.

The NCOS population was created in 2019 and the moderate resiliency score is representative of the conditions that existed at that time. The population is quickly evolving with changes in site conditions occurring rapidly as Astragalus pycnostachyus var. lanosissimus individuals mature along with associated planted and naturally recruiting species. The resiliency score is expected to improve with continuing management and monitoring of the NCOS population.

The CSMR and McGrath State Beach populations exhibit low resiliency. Both have had few to no adult plants in recent years and the seed bank may be declining. Currently, habitat conditions are poor to moderately suitable resulting from high amounts of invasive species, stabilized conditions, and soils becoming potentially too dry. Because we do not understand how long a natural population can persist, it is impossible to say whether or not the period for which adults survived and reproduced was normal or not. Considering the amount of effort that was required to influence the survival of relatively small numbers of individuals (less than 100 per site), it is likely that these populations succumbed rather quickly to stochastic variations in the environment, primarily periods of drought and flooding. The inability of seed to reestablish for appreciable periods of time in different locations following flooding suggests that there is not enough space and spatial variation to allow for the natural dispersal of the species within each population.

7.2 REPRESENTATION

The rediscovered population of Astragalus pycnostachyus var. lanosissimus at the North Shore site represents a genetic bottleneck where the genetic diversity is established and constrained by a small founding population. Outplanted populations prior to 2014 were derived from 13 maternal lines collected from the North Shore population and propagated by Rancho Santa Ana Botanic Garden, Santa Barbara Botanic Garden, and Coal Oil Point Reserve. In 2014 seed was collected from 22 maternal lines, again from the North Shore population, and used to produce individuals for the McGrath Parcel and NCOS site. It is not known how genetically similar the more recent maternal lineages are from the historical collections. Representation was low when all nine populations had surviving adult individuals because the genetic diversity from the original 13 maternal lines all came from the same population, and would not have been likely to represent a wide range of genetic adaptive capacity. It is unlikely that representation increased

46 between the original seed collection and more recent seed collection due to a lack of time and directional pressure. Founder events increase the likelihood of homozygosity and the likelihood that disease and shifts in environmental conditions will lead to failure across all populations of the species because genetic diversity is too low to facilitate adaptation. The actual genetic diversity that is represented by the founding maternal lines is not known, and it is possible that additional diversity exists in the seed bank within the North Shore population, but there is currently no plan to evaluate this.

Representation has decreased since the 2002 to 2004 outplanting effort. Only one individual remains at the Carpinteria Salt Marsh Reserve and represents the sole naturally recruited and unmanaged individual. The plants within the McGrath Parcel population were grown from seed derived from the founding maternal lines in 1997, collected from the North Shore population. Representation will continue to be low until either a new natural population is discovered or that introduced populations persist for a long enough period in a diverse array of habitats to promote niche specialization.

7.3 REDUNDANCY

There are two extant populations with high resiliency and four populations with moderate resiliency; reproductive individuals are only present at four of these six populations. Currently adult individuals only exist at the Carpinteria Salt Marsh Reserve (one), NCOS restoration site (150), McGrath Parcel (115), and the North Shore site (198). A viable seed bank is assumed to exist at the COPR Pond site and McGrath State Beach. Redundancy is low because there are few populations with adequate resiliency, and they are all within 63 kilometers (39 miles) of each other. Changes in precipitation patterns and temperature are likely to affect each population in the same manner. The source or mechanism that supports the water table of each population is unique to that population (e.g. lagoon, ocean, lake, oil pan), providing some amount of redundancy in the hydrologic suitability of each of the populations. A drop in the water table of one population is unlikely to directly affect another population. However, the factors that led to a change in water table (e.g. declining annual precipitation) may affect multiple populations. Redundancy remains low even if all outplanted populations that once had adult individuals, but no longer do, are considered to exist as a viable seed bank. Susceptibility to regional catastrophic events such as extended drought would affect all equally due to geographic proximity. Redundancy is likely to remain low in perpetuity because there are not enough potential suitable locations for reintroduction throughout the species’ historical range. Ex situ seed bank collections are stored at Rancho Santa Ana Botanic Garden, Santa Barbara Botanic Garden, and the National Laboratory for Genetic Resource Preservation.

8 FUTURE CONDITION

We use 20 to 30 years as our future timeframe as it encompasses a period of time that may experience similar environmental variations as has been observed since the rediscovery of the species in 1997, and it provides a reasonable ability to predict the outcome of currently proposed and plausible future land use and land management actions.

The future condition of past, current, and potential reintroduction sites for Astragalus pycnostachyus var. lanosissimus is dependent primarily upon the trajectory of current

47 populations, land use, management actions, and climate change. There is very little room for change in land use around current and historical populations because nearly all land has either been developed or is already owned and managed for ecological value, recreation, or open space. Management actions are similarly not likely to change from current practices except for variation in the level of effort directed towards vegetation management (non-native species and native woody species control) and frequency and intensity of reintroduction efforts. Climate change models provide a robust assessment of likely changes over several decades to one hundred years. The effects of climate change that are most likely to affect populations of Astragalus pycnostachyus var. lanosissimus are frequency and amount of precipitation, changes to average and extreme temperatures, flooding intervals, water table fluctuations, shifts in vegetation community, and sea level rise.

8.1 LAND USE AND LAND MANAGEMENT

The immediate and surrounding land use of past and current reintroduction sites is not likely to change because all sites occur on land designated for preservation while also being surrounded by either existing development and/or additional protected land. Specific management actions to promote Astragalus pycnostachyus var. lanosissimus are being taken at the North Shore site, McGrath Parcel, and North Campus Open Space (NCOS) restoration site. At all other populations there is currently no specific management actions being taken to promote Astragalus pycnostachyus var. lanosissimus. Surrounding land management that benefits the species includes non-native species control, restoration of native habitat, and restoration of natural hydrology. The degree of beneficial land management that is occurring next to populations varies by site, with the greatest amount of activity occurring at Coal Oil Point Reserve (and the adjacent NCOS restoration) and Carpinteria Salt Marsh Reserve. Planning for a large restoration project surrounding the Ormond site has begun and there is interest in creating habitat for Astragalus pycnostachyus var. lanosissimus, although the project is in early development (ESA 2019, entire). There is currently no plan to manage the Mandalay State Beach site for Astragalus pycnostachyus var. lanosissimus because the habitat is not considered suitable. The McGrath State Beach site has no active land management activities and none are planned. The nearby management of the McGrath Parcel is geographically separated, so that recruitment from the McGrath Parcel to McGrath State Beach is not likely. The suppression of non-native species at the McGrath Parcel may inhibit the spread of non-native species at McGrath State Beach, although the site already contains non-native species (Carpobrotus spp.).

The exceptions to the above characterized land use and land management are the North Shore site and McGrath Parcel. The North Shore site is still subject to indirect effects from the proposed housing development that surrounds the population. Grading for roads and housing pads, compaction, and drainage alteration have the potential to affect the North Shore population. Following development, invasive species from landscaping and human recreation within the North Shore population enclosure may have further negative impacts. A naturally functioning population may not again occur at the North Shore site despite impacts potentially being mitigated through management activities.

The North Shore site is to be managed in perpetuity and the McGrath Parcel will be managed from 2016 through 2025 (Arcadis 2016, p. 1; Arcadis 2018b, p. 2-1). As a result, the North Shore site is expected to persist while the future of the McGrath Parcel after 2025 is unknown. The

McGrath Parcel will either decline and exist only as a seed bank within 5 – 10 years after the 2025 date, as has been observed at other reintroduction sites where management was removed, or it will continue to contain and produce reproductive plants. Key management activities that facilitate continued establishment of reproducing individuals include soil moisture monitoring, irrigation, supplemental planting (at the McGrath Parcel only), weeding, and controlling long lived perennial native vegetation. From 1997 to 2009 the North Shore population persisted without any regular management practices. Weeds were periodically removed although the frequency and intensity of this management has not been recorded. The irregular, and likely infrequent weeding, suggest that the site had maintained some level of natural suitability for the species through 12 years of environmental cycles. The population during this time varied between about 30 and 350 individuals, and represents the best example of how a naturally occurring population responds to annual variations in environmental conditions. The effect of the soil remediation activities from 2006 to 2009 also demonstrate that adjacent land use may have significant effects on hydrology that determines the suitability of past, current, and future reintroduction sites.

8.3 CLIMATE CHANGE

The aspects of climate change that are considered here are frequency and amount of precipitation, changes to average and extreme temperatures, flooding intervals, water table fluctuations, shifts in vegetation community, and sea level rise. The Western Regional Climate Center, Desert Research Institute prepared a report detailing projected changes in climate within Ventura County. This report uses the Localized Constructed Analog dataset, the Representative Carbon Pathway (RCP) 8.5 scenario, and 32 downscaled climate models to estimate changes within Ventura County (Oakley et al., 2019 p. 10-14). The RCP 8.5 scenario is a model variable that estimates the contribution of greenhouse gas emissions and associated effects. The RCP 8.5 scenario assumes global trends in carbon emissions will continue to rise as they have been throughout the 21st century. This data has also been used in the 4th California Climate Assessment and is available online through Cal-Adapt (Langridge 2018, entire; Cal-Adapt 2019). The Western Regional Climate Center report is useful for its specificity to Ventura County when evaluating the effects of climate change on Astragalus pycnostachyus var. lanosissimus.

8.3.1 Frequency and Amount of Precipitation

Historically, annual precipitation averages 39 cm (15.33 in) at Oxnard near many of the Ventura County reintroduction sites (Oakley et al. 2019, p. 4). An 11-year running mean of annual precipitation between 1896 and 2018 suggests no trend in precipitation amounts during this period. A decrease in precipitation amount is observable if the time period is limited to 2000 through 2018 although the decrease fits within historical oscillations of precipitation variability (Oakley et al. 2019, p. 9).

The amount of precipitation predicted by climate modeling is uncertain, with no change, less precipitation, and more precipitation all being possible future scenarios depending on the model used. However, regardless of changes to the amount of precipitation, precipitation events are predicted to become more intense and less frequent. (Oakley et al. 2019, p. 26). This shifts when and how much rain falls and likely has effects on germination, survival, water table persistence, and flooding. The models suggest that on average there will be a 20 percent decrease in fall

49 precipitation days, a seven percent decrease in winter precipitation days, and an 11 percent decrease in spring precipitation days – all with little to no change in the annual total. This suggests that rain events will be more intense and that there will be significantly more precipitation across fewer days (Oakley et al. 2019, p. 26). Models suggest that the greatest change will be increased intensity and precipitation totals in the winter months (December, January, and February) (Oakley et al. 2019, p. 28). The potential effects of greater intensity include increased flooding as more rain falls over shorter periods of time, less ground water recharge as saturated soils give way to overland flow towards drainage systems, river channels, and the ocean, increased soil drying from fewer precipitation days, and shifts in germination cues.

8.3.2 Average and Extreme Temperatures

Maximum temperatures in Ventura County have averaged 19 degrees C (66.1 degrees F) in December to 24 degrees C (75.9 degrees F) in August and minimum temperatures have averaged 7 degrees C (44.5 degrees F) in December to 15 degrees C (58.8 degrees F) in August. Both minimum and maximum temperatures have been increasing based on data between 1896 and 2018 (Oakley et al. 2019, pp. 4, 7).

Over the next 20-30 years, both maximum and minimum temperatures are expected to increase across all seasons in coastal Ventura County by two to three degrees F (about 1 degree C) (Oakley et al. 2019, pp. 16-17). Additionally, the number of days with temperatures greater than 80 degrees F (27 degrees C) is expected to increase by about 35 to 45 days. Increases in temperatures are likely to increase soil drying and heat stress as well as increasing the rate of evaporation of standing water, all changes that have the potential to decrease the survivorship of Astragalus pycnostachyus var. lanosissimus seedlings and adults. Germination may be less affected by these increases in temperature because germination typically follows flood or rain events. However, the survivorship of newly germinated seed is likely to decrease because of increased stress from heat effects. This decreased survivorship may result in a depletion of the seed bank due to continued germination of seed but with mortality occurring before reproductive maturity.

8.3.3 Shifts in Vegetation Communities

Shifts in vegetation community composition are likely to occur as a result of changes in climate and may impact the long term suitability of the North Shore site and past, present, and future reintroduction sites. All California macrogroups of vegetation are expected to have moderate to high risk of vulnerability to climate change (Thorne et al. 2016, p. 1). This means that all vegetation communities are susceptible to portions of their current range becoming unsuitable. It is also possible that previously unsuitable areas for a given macrogroup will become suitable as physical parameters that were previously unfavorable become favorable. Vegetation communities migrating higher in elevation along temperature gradients or moving upland as sea levels rise along hydrological gradients are typical examples of such shifts. However, the ability of a vegetation macrogroup to migrate assumes that natural seed dispersal pathways are available and that undeveloped land exists along dispersal pathways.

Astragalus pycnostachyus var. lanosissimus occurs in association with five macrogroups modeled by Thorne et al. (2016, entire): Warm Southwestern Riparian Forest, California Coastal Scrub, California Annual and Perennial Grassland, Western North American Freshwater Marsh, and North American Pacific Coastal Salt Marsh. Warm Southwestern Riparian Forest, California Coastal Scrub, and California Annual and Perennial Grassland are ranked at mid-high risk of vulnerability and Western North American Freshwater Marsh, and North American Pacific Coastal Salt Marsh are ranked as high (Thorne et al. 2016, p. 3; Table 4). Estimates of the percent of existing habitat that will become unsuitable, have no change, or become newly suitable based on the climate model suggesting hotter and drier climate using the RCP 8.5 emission scenario are shown in Table 4 based on data within Thorne et al. (2016, pp. 105-113; 123-140, 186-194; 204-212). We report the hotter and drier scenario data because it better matches the predicted climate where Astragalus pycnostachyus var. lanosissimus occurs better than a model that predicts warmer and wetter conditions.

Table 4. Results of sensitivity and adaptive capacity modeling and the resulting change in suitability of existing habitat for five vegetation macrogroups associated with Astragalus pycnostachyus var. lanosissimus. Mean Newly No Newly Net Vegetation Vulnerability Unsuitable Change Suitable Change Macrogroup Rank (%) (%) (%) (%) Warm Southwest Mid-High 20 80 114 + 94 Riparian Forest California Coastal Mid-High 28 72 31 + 3 Scrub California Annual and Mid-High 48 52 52 + 4 Perennial Grassland Western North American Freshwater High 93 7 39 - 54 Marsh North American Pacific High 92 8 3 - 89 Coastal Salt Marsh Data from Thorne et al. 2016 pp. 3; 105-113; 123-140; 186-194; 204-212.

All vegetation macrogroups are likely to have portions of their current range become unsuitable under the hotter and drier scenario with RCP 8.5. The aquatic vegetation macrogroups (Western North American Freshwater Marsh and North American Pacific Coastal Salt Marsh) are predicted to have 92 and 93 percent of their current range become unsuitable. This change results from both decreases in precipitation causing upland margins to dry out as well as increases in sea level converting salt marshes to fully aquatic habitat. Notably, the amount of habitat that becomes suitable for these macrogroups is very limited because these macrogroups are often surrounded by development or topography that inhibits migration of the key vegetation species and/or does not support the necessary hydrology. The Warm Southwestern Riparian Forest, California Coastal Scrub, and California Annual and Perennial Grassland macrogroups are more

resilient to climate change, and have a greater predicted amount of newly suitable potential habitat, though migration potential within the range of the species is still limited by development and barriers to dispersal.

All populations of Astragalus pycnostachyus var. lanosissimus are bordered by roads and commercial, residential, and industrial development that inhibit migration of habitat, and all populations occur in areas that are spatially restricted and do not allow migration of habitat within their current extents. The result of this is likely a narrowing of the potentially suitable microsites at each of the populations that could be suitable for supporting the species. With smaller areas of suitability, it is less likely that disturbance events will occur in opportunistic areas for recolonization and more likely that seed may become dispersed to areas that are unfavorable for germination. Since the species is restricted to coastal habitats, it is also not likely that newly suitable areas can be relied upon to mitigate the loss of currently suitable habitat because very little undeveloped land exists along the California coast where Astragalus pycnostachyus var. lanosissimus occurs.

8.3.4 Sea Level Rise

Sea level has been variably increasing along the Southern California coast between Santa Barbara and Ventura Counties. The sea level is rising at a rate of 1.16 mm/yr (0.05 in) in Santa Barbara based on data between 1973 and 2018, and at a rate of 3.22 mm/yr (0.13 in) at Rincon Island in Carpinteria based on data between 1962 and 1990. These data suggests that current rates of increase will result in a sea level increase of 11.6 cm (0.38 ft) in Santa Barbara and 32.3 cm (1.06 ft) in Carpinteria in the next 100 years (NOAA 2019, NA).

However, rates of sea level rise are predicted to increase, with areas along the California coast expected to experience 30 cm (1 ft) of sea level rise by 2050 (Sievanen et al. 2018, p. 16). The effects of sea level rise include increased ocean flooding of coastal areas, changes in ground water chemistry, and shifts in vegetation communities along the coast. The flooding potential of coastal areas throughout California has been modeled based upon different sea level rise and ocean condition scenarios. If 25 cm (10 in) of sea level rise occurs and current annual storm frequency continues, the flood model predicts increase frequency, depth, and length of flooding at Coal Oil Point Reserve, Carpinteria Salt Marsh, and Ormond Beach. The North Shore site is located at too high an elevation for ocean based flooding to cause inundation and the McGrath State Beach, McGrath Parcel, and Mandalay State Beach sites occur behind back dunes that are not likely to flood from sea level rise under this scenario. Ocean based flooding begins to affect these areas at 175 cm (69 in) of sea level rise (Ballard et al. 2016, NA).

The dominant effect of sea level rise on Astragalus pycnostachyus var. lanosissimus will be an increase in salinity at sites that are likely to have direct inundation with ocean water through flooding or through increases to salinity in the ground water that the species relies upon for persistence during dry periods and periods of drought. The result is likely a decrease in the suitability of habitat and potential for increased mortality of existing populations. Habitat migration to higher elevations is not a likely natural mitigation factor because there is little room for migration, resulting in an overall decrease of potentially suitable habitat for the species.

9 FUTURE SCENARIOS

The distribution of Astragalus pycnostachyus var. lanosissimus is currently limited to a single natural population that is under intense management for the preservation of the species, two reintroduction sites that are similarly managed, and a single plant that has naturally recruited from past reintroduction efforts that is not currently managed for the benefit of the species. Two additional populations presumably exist only as seed banks in areas where suitable habitat is present and there is recent history of the presence of reproductive adults. As a result, the level and consistency of land use and land management actions including native and non-native species management, herbivory management, soil moisture monitoring, supplemental watering, and reintroduction efforts are dominant factors in predicting the future condition of the species. Development pressure, restoration of habitat, and climate change are additional factors that will influence the resiliency, representation, and redundancy of Astragalus pycnostachyus var. lanosissimus.

Table 5 presents three plausible future scenarios given current trends in land management and land use, developmental pressure, and possible future climate conditions. The first scenario describes a future in which the current trends in Astragalus pycnostachyus var. lanosissimus population trajectories continue with similar levels of land use and land management. The climate in this scenario changes as predicted under the average of models using RCP 8.5 (see Oakley et al. 2018, entire). The second scenario describes a future in which the current trajectories in populations are bolstered by beneficial increases in land use and land management, including additional reintroduction attempts, while climate continues to change as predicted based on the average of models using RCP 8.5. In the third scenario, land use and land management practices decline, with the climate continuing to change as predicted based on the average of models using RCP 8.5. Different RCP values are not considered because even under more optimistic modeling, the climate continues to have negative impacts on the species’ habitat and life cycle. Additionally, the species is currently reliant upon human actions to be both sustained and introduced to new areas. As a result, under any climate scenario human activities will have proportionately greater effects on resiliency, representation, and redundancy of the species.

Table 5. Summary of potential future scenarios influencing the resiliency, representation, and redundancy of Astragalus pycnostachyus var. lanosissimus. Scenario 2 Scenario 3 Scenario 1 Factor (Increasing (Declining (Continuation) management) management) Land management Currently managed Current management Management populations continue continues at existing continues only at the to be managed for the sites, with increases North Shore site. benefit of the species. in beneficial McGrath parcel not No change in management at managed after 2025. management of all current and potential North Campus Open other current and reintroduction sites. Space restoration site potential funding ends within reintroduction sites. 10 years, restricting management. No other sites managed for the species. Reintroductions Supplemental Additional No additional planting occurs at reintroduction sites reintroductions and only McGrath Parcel. introduced. no supplemental Supplemental planting of current planting at current sites. reintroduction sites as needed.

9.1 FUTURE SCENARIO 1 (CONTINUATION)

In Future Scenario 1, there is a continuation of current land use, land management, and reintroduction efforts. Current trends in the populations are expected to continue with declining numbers of reproductive adult individuals at all sites except for the North Shore site and the McGrath Parcel where current management activities support the biological needs of the species. Negative impacts from the development of the North Shore site are anticipated, primarily through further alteration of hydrology affecting the depth and persistence of the water table, introduction of non-native species, and unintentional mortality from trespass into the areas where Astragalus pycnostachyus var. lanosissimus occurs. However, monitoring of the North Shore site and subsequent management actions are likely to be successful in maintaining conditions that support the continued persistence of the species.

Restoration activities at the North Campus Open Space restoration site are likely to have positive influences on associated species and vegetation cover facilitating the survival of individuals planted in 2019. Those adults will contribute to a growing seedbank as they reach reproductive maturity. The success of this restoration project will provide future opportunity for introducing Astragalus pycnostachyus var. lanosissimus into newly suitable habitat in other areas within the NCOS restoration site. The expansion of natural environments within the broader Devereux

Slough ecosystem may also provide some ability for the migration of suitable habitat reducing the negative effects of climate change at this specific location.

At the Coal Oil Point Reserve pond site vegetation cover increases and the associated species shift more towards later successional species and/or invasive species resulting a decrease of resiliency but not so much that the category changes from moderate to low. The absence of direct management efforts has established site conditions that are not optimal, but are adequate, for germination and survival. It is also possible that future natural disturbances from the associated pond shift conditions to become more favorable but we have chosen to evaluate the sites as an extrapolation of current conditions.

The Ormond Beach Restoration and Public Access Project is another restoration project that may benefit a past reintroduction attempt and provide opportunity for additional new introductions. The project is in early planning stages and an estimated construction date is currently unknown.

Without additional management, Carpinteria Salt Marsh Reserve and McGrath State Beach will increasingly become unsuitable due to a combination of competition from both non-native and native vegetation inhibiting germination of the seed bank, herbivory suppressing any seeds that do germinate, and the effects of climate change resulting in drier and more saline conditions despite periods of greater rain. The resiliency of these sites will remain low.. Similarly, potential suitable habitat elsewhere in Santa Barbara, Ventura, and Los Angeles Counties will become less suitable with time in the absence of direction management.

Under Future Scenario 1 the conditions at the North Shore site and McGrath Parcel remain stable due to management efforts, and resiliency remains high. Continued management efforts at the NCOS restoration site will improve conditions through associated species introductions and control of competing species, resulting in higher resilience. Resiliency decreases but the category does not change for the COPR pond site because that site has been unmanaged for a period of time where we do not expect to observe significant decline in habitat suitability with continued lack of management. Carpinteria Salt Marsh Reserve and McGrath State Beach are expected to continue to have low resiliency with deteriorating changes due to predicted loss of adult plants (CSMR) and negative changes in vegetation cover and associated species (CSMR and McGrath State Beach). Under Scenario 1, Astragalus pycnostachyus var. lanosissimus populations generally decline without management, leading to conservation reliant populations that are under constant threat of local extirpation, and extinction of the species outside of botanical gardens and ex situ seed banks (Table 6).

Representation is low under this scenario because all populations have been established using seeds collected from a small number of individuals from the North Shore site. Founder effects are likely to persist where the species still occurs and genetic diversity is likely to decrease as populations decline. The current representation of genetic diversity may not be diverse enough to allow for adaption to the effects of climate change.

Under Future Scenario 1, no populations are expected to become extirpated but unmanaged populations (COPR pond, Carpinteria Salt Marsh Reserve, McGrath State Beach) may only persist as a seed bank until more favorable conditions naturally return to those sites. As a result

redundancy may be considered to either be maintained at its current state or to slightly decrease because of the loss of reproductive adults from unmanaged sites leading to decreased resiliency and increased chance of extirpation. There are no predicted new population discoveries or introductions in this scenario and the range of the species is narrow enough that a catastrophic event such as a tsunami resulting from an earthquake may negatively impact all populations. Somewhat similarly, severe or prolonged drought is likely to be uniform across the species range and would affect all populations similarly. A buffer against total loss of redundancy and extinction are the holdings of the species in botanic gardens and ex situ seed banks.

Table 6. Resiliency (Future Scenario 1) of Astragalus pycnostachyus var. lanosissimus populations. Currently extant populations were scored as low, moderate, high (0, red; 1, yellow; 2, green; respectively) for each habitat need. The average (mean) score was then used to provide an overall rank. Populations that scored 0 to 0.66 had low resiliency. Populations were considered moderately resilient if scored between 0.67 and 1.33. Populations with high resilience scored greater than 1.33. The North Campus Open Space restoration site is still in development and the evaluation of that site is based on estimates (est).

at 18 inches

Site Dynamic Environment Vegetation Cover Species Associated Water table moisture Soil Reproductive adults Seed bank Overall

North Shore 1.43

Coal Oil Point Reserve Pond 0.71

North Campus Open Space est est est est est est est 1.86

Carpinteria Salt Marsh Reserve 0.43

McGrath State Beach 0.43

McGrath Parcel 1.86

9.2 FUTURE SCENARIO 2 (INCREASING MANAGEMENT)

Under Future Scenario 2, management activities that benefit Astragalus pycnostachyus var. lanosissimus increase at past and current reintroduction sites. Key management activities that increase the suitability of habitat include non-native and native species management to reduce competition for juvenile and adult individuals of the species, controlling herbivory through exclusion fencing, removing snails, and decreasing shrub and tree vegetation in order to reduce cover for and thus discourage herbivorous mammals. Currently, supplemental planting is used infrequently at introduced sites, only when reproducing adults have not been present for several

years and when conditions are believed to be suitable. This is done to both check site suitability at that time and to increase the local seed bank if the supplemental plants successfully produce seed. Supplemental watering is used to establish populations at initial introduction or when supplemental planting occurs. Additional supplemental water is used sparingly to reduce the effects of drought and desiccation from changes in seasonal precipitation. These activities already occur at the North Shore site and the McGrath Parcel and will continue under this scenario.

Additional sites for reintroduction are identified and managed under Future Scenario 2. This includes the North Campus Open Space (NCOS) Restoration Project and the Ormond Beach Restoration and Public Access Project. Restoration activities at the NCOS restoration site are likely to have positive influences on associated species and vegetation cover facilitating the survival of individuals planted in 2019. Those adults will contribute to a growing seedbank as they reach reproductive maturity. The success of this restoration project will provide future opportunity for introducing Astragalus pycnostachyus var. lanosissimus into newly suitable habitat in other areas within the NCOS restoration site. The expansion of natural environments within the broader Devereux Slough ecosystem may also provide some ability for the migration of suitable habitat reducing the negative effects of climate change at this specific location. In this scenario we also expect a new population to be introduced to a unique location at the newly restored Ormond Beach Restoration and Public Access Project (not at the location of the extirpated Ormond Beach site).

The Coal Oil Point Reserve pond site, Carpinteria Salt Marsh Reserve, and McGrath State Beach will have increased management resulting in the reestablishment of reproductive adults in these populations. Weed management and supplemental planting are likely to have the greatest effect at these sites.

Development surrounding the North Shore site has negative impacts on the North Shore population, but these will be mitigated through continued and/or additional measures as necessary because of the requirement to manage in perpetuity. The North Shore population continues to be conservation reliant in this scenario.

The effects of climate change are still significant in this scenario, with decreases in winter precipitation frequency, increases in winter precipitation intensity, and increases in average, maximum, and minimum temperatures. The results increase stress and mortality on existing and potential future Astragalus pycnostachyus var. lanosissimus populations while decreasing the amount of available suitable habitat. The effects are offset only slightly through management activities since they cannot directly address declining water tables and broad shifts in precipitation patterns and temperature. The management under this scenario does improve habitat locally at all sites, as well as potential sites, resulting in a greater ability for migration of vegetation and suitable habitat.

Resiliency of all populations are considered to be high under Future Scenario 2. The largest changes in resiliency occur at the COPR pond, NCOS restoration, Carpinteria Salt Marsh Reserve, and McGrath State Beach sites. The management activities currently ongoing at the North Shore site and McGrath Parcel continue, maintaining high resiliency. The high resiliency

58 of these populations is tempered by the fact that they become increasingly conservation reliant with increasing human management. Any loss of management activities would likely lead to a decline in resiliency.

Despite increased resiliency, new introductions, and supplemental planting, representation is very low under this scenario because all populations have been established using seeds collected from a small number of individuals from the North Shore site. Founder effects are likely to persist where the species still occurs and at locations where it was introduced. The current representation of genetic diversity may not be diverse enough to allow for adaption to the effects of climate change. Representation could increase if new populations were identified but this is not considered likely and was not included in any of the future scenarios.

Under Future Scenario 2 redundancy increases because management facilitates the persistence of populations through management actions and a new population is established at the Ormond Beach Restoration and Public Access Project. However, even with the increased number of populations, the range of the species is narrow enough that a catastrophic event such as a tsunami resulting from an earthquake may negatively impact all populations. Somewhat similarly, severe or prolonged drought is likely to be uniform across the species range and would affect all populations similarly. A buffer against total loss of redundancy and extinction are the holdings of the species in botanic gardens and ex situ seed banks.

Table 7. Resiliency (Future Scenario 2) of Astragalus pycnostachyus var. lanosissimus populations. Currently extant populations were scored as low, moderate, high (0, red; 1, yellow; 2, green; respectively) for each habitat need. The average (mean) score was then used to provide an overall rank. Populations that scored 0 to 0.66 had low resiliency. Populations were considered moderately resilient if scored between 0.67 and 1.33. Populations with high resilience scored greater than 1.33. The North Campus Open Space restoration site is still in development and the evaluation of that site is based on estimates (est).

at 18 inches

Site Dynamic Environment Vegetation Cover Species Associated Water table moisture Soil Reproductive adults Seed bank Overall

North Shore 1.57

Coal Oil Point Reserve Pond 1.86

North Campus Open Space est est est est est est est 1.86

Carpinteria Salt Marsh Reserve 1.57

McGrath State Beach 1.71

McGrath Parcel 1.86

9.3 FUTURE SCENARIO 3 (DECLINING MANAGEMENT)

Under Future Scenario 3 management effort declines at all sites except for the North Shore site. The North Shore site is not expected to decline because of legal agreements to maintain the population. The McGrath Parcel continues with the current management effort through 2025 (the end of the 10 year maintenance period required by development permits) and then ceases. The lack of management at all other past reintroduction sites results in prolonged absence of reproducing adults punctuated with periods of natural recruitment following floods or heavy rain. However, establishment of natural recruits generally fails due to a combination of non-native and native species competition, herbivory, and decreasing water tables, increasing salinity, and hotter, drier spring, summer, and fall months. The failure of natural recruitment to produce

60 reproductive plants results in a depletion of the seed bank, causing loss of resiliency that in some cases lead to population extirpations that are not expected to return if habitat and conditions were to improve.

In this scenario, the restoration project at the North Campus Open Space restoration site is constructed and maintained for a period of time before management declines and habitat suitability decreases. Populations of Astragalus pycnostachyus var. lanosissimus may persist for short periods if introduced, but the lack of permanent long term management leads to extirpation as has been observed with previous reintroductions.

The effects of climate change are exacerbated by the declining effort to manage habitat for the species, resulting in accelerated deterioration of previously suitable habitat. Future Scenario 3 results in only the North Shore continuing with high resiliency due to active management required through regulatory action. The COPR pond site decreases in resiliency but does not become extirpated due to its history of lack of management that suggests the site may be able to withstand prolonged periods of absent management. The NCOS restoration site similarly drops in resiliency but does not fall into the low category due to its position within the Devereaux Lagoon system. All other populations fall into the low resiliency category and become extirpated within 20 to 30 years depending on when management activities stop.

The already low genetic diversity and representation is further reduced by the extirpation of three populations. However, the amount of genetic diversity that is lost due to population extirpations may be relatively low compared to species with naturally occurring populations because the founding individuals for each introduced population were sourced from the same genetic material at the North Shore site. It is likely that not enough time has passed since populations were introduced to have resulted in genetically unique ecotypes.

Redundancy under this scenario decreases from the extirpation of three populations and the lowered resiliency of two others. A buffer against total loss of redundancy and extinction are the holdings of the species in botanic gardens and ex situ seed banks.

Table 8. Resiliency (Future Scenario 3) of Astragalus pycnostachyus var. lanosissimus populations. Currently extant populations were scored as low, moderate, high (0, red; 1, yellow; 2, green; respectively) for each habitat need. The average (mean) score was then used to provide an overall rank. Populations that scored 0 to 0.66 had low resiliency. Populations were considered moderately resilient if scored between 0.67 and 1.33. Populations with high resilience scored greater than 1.33. The North Campus Open Space restoration site is still in development and the evaluation of that site is based on estimates (est). The use of an “x” adjacent to the resiliency score indicates a reintroduction site that was expected to become extirpated under the considered scenario.

at 18 inches

Species

Site Dynamic Environment Vegetation Cover Associated Water table moisture Soil Reproductive adults Seed bank Overall

North Shore 1.43

Coal Oil Point Reserve Pond 0.71

North Campus Open Space est est est est est est est 0.86

Carpinteria Salt Marsh Reserve 0.43x

McGrath State Beach 0.43x

McGrath Parcel 0.57x

10 OVERALL SYNTHESIS

Evaluating the status of Astragalus pycnostachyus var. lanosissimus is challenging because before 1997 the species was believed to be extinct and it existed under natural (unmanaged) conditions only from 1997 to 2009. The species was listed under the Federal Endangered Species Act in 2001, with the primary threats being development resulting in direct loss of the sole population, unanticipated human-caused and natural events that could eliminate the sole population, and competition from non-native plants. The list of threats to the species was limited because very little was known about the biological needs and life history of the species. By 2005, populations had been introduced to seven locations with varying success, and all sites were initially managed. Between ~2005 and 2009, all populations except the North Shore population could be considered conservation reliant because they did not persist without management. Following the alteration of hydrology at the North Shore site in 2009, and the subsequent installation of an irrigation system, all populations became conservation reliant. By 2012, a more complete understanding of the biological needs and life history of Astragalus pycnostachyus var. lanosissimus had been developed; however, by then most populations no longer had reproductive individuals, or contained very few. In 2019, reproductive individuals only exist at the North Shore site and the McGrath Parcel, both under active management that includes supplemental watering and non-native and native species control. Supplemental planting has also been used at the McGrath Parcel following high mortality from flood events. A single plant was found at Carpinteria Salt Marsh in 2019, indicating that the site may still support a population in the form of a dormant seed bank. The North Campus Open Space (NCOS) restoration site was planted with Astragalus pycnostachyus var. lanosissimus between October and December 2019 and represents the most recent effort to established a self-sustaining population. The Coal Oil Point Reserve (COPR) pond site and McGrath State Beach are still considered extant populations despite not having reproductive adults because they likely contain a viable seedbank and suitable habitat.

The resiliency of extant populations varies based on the scenario that is considered (Table 9). Under current conditions, the North Shore population and the McGrath Parcel population have high resiliency. This is largely due to the continued management activities at each population that facilitate adequate soil moisture, vegetation cover, and species composition. The COPR pond and NCOS restoration site have moderate resiliency. Carpinteria Salt Marsh Reserve (CSMR), and McGrath State Beach have low resiliency. Of these sites, adult plants are present at only the NCOS restoration site and a single plant at CSMR. Adult plants were present at the COPR pond in 2018 and at McGrath State Beach in 2012. However, the seed bank is believed to be viable at both sites and conditions are likely to support germination and adult plants in the future. This is in contrast to the COPR lagoon site, Mandalay State Beach, and Ormond where there is likely a seed bank from past reintroduction efforts, but the sites are no longer likely to support germination and adult plants. As a result we consider those populations to be functionally extirpated.

Table 9. Summary of overall resiliency of Astragalus pycnostachyus var. lanosissimus populations under current conditions and three future scenarios. Extant populations were scored as low, moderate, high (0, red; 1, yellow; 2, green; respectively) based on the mean score of habitat needs (see section 7.1 and section 9 for a description of the analysis). The North Campus Open Space restoration site is still in development and the evaluation of that site is based on estimates (est). The use of an “x” adjacent to the resiliency score indicates a reintroduction site that was expected to become extirpated under the considered future scenario.

(Continuation) Future Scenario 1 Future Scenario 2 Future Scenario 3 Current Condition (Declining Management (Declining Site Management) (Increasing

North Shore 1.43 1.43 1.57 1.43 Coal Oil Point Reserve 1.00 0.71 1.86 0.71 Pond North Campus Open 0.86 1.86 1.86 0.86 Space Carpinteria Salt Marsh 0.57 0.43 1.57 0.43x Reserve

McGrath State Beach 0.57 0.43 1.71 0.43x

McGrath Parcel 1.86 1.86 1.86 0.57x

Resiliency changes in proportion to current management effort under Future Scenario 1. The North Shore and McGrath Parcel continue to have high resiliency and the NCOS restoration site increases from moderate to high resiliency because of the continued restoration work. Conversely, the Carpinteria Salt Marsh Reserve and McGrath State Beach decrease in suitability and remain having low resiliency. The COPR pond site decreases in suitability but remains moderately resilient because the absence of management has occurred for a long enough period where we can assume that it will continue as observed in the past under the 20 to 30 year timeframe considered for the Future Scenarios.

Under Future Scenario 2 there is an increase in the amount of management at each population that leads to improvements in associated species and vegetation cover, and when coupled with reintroductions and maintenance, increase the amount of reproductive adults and further establish the seed bank. All populations are considered to have high resiliency under Future Scenario 2.

Conversely, management effort declines at all sites under Future Scenario 3 except at the North Shore site where regulatory requirements dictate the continued persistence of the population. This scenario assumes that management at the McGrath Parcel and NCOS restoration site stops after 10 years and in the remaining 10 to 20 years the populations decline similarly to what has been observed with past reintroduction sites that were unmanaged for extended periods of time. The decline in management effort results in the loss of resilience of two populations and the extirpation of three populations.

Representation, adaptive capacity, across all populations of Astragalus pycnostachyus var. lanosissimus is low under current conditions. No new natural populations have been discovered and all reintroduction sites have been derived from the same maternal lines, including the NCOS restoration site. The range of ecological settings and geography across which the species is found remains limited. Representation remains low across all future scenarios unless a new natural population is discovered and shown to have a different genetic structure from the existing populations.

Redundancy, ability to withstand catastrophic events, is low, exacerbated by the narrow range of the species, existing only in Santa Barbara and Ventura Counties in small patches along the coast. Furthermore, the COPR pond and NCOS restoration site populations are part of the same lagoon complex, and the McGrath State Beach and McGrath Parcel populations are adjacent to each other. A catastrophic event such as prolonged inundation from a tsunami would likely affect each of these pairs equally, if not all populations along the immediate coast (only the North Shore population exists at an elevation and distance from the ocean that provides some protection against tsunami inundation). Redundancy remains low under Future Scenario 1 with no new populations being introduced. Redundancy slightly increases under Future Scenario 2 with the introduction of a new population at the Ormond Beach Restoration and Public Access Project but still remains low. Redundancy decreases under Future Scenario 3 resulting from the extirpation of three populations. For all scenarios, holdings of the species in botanic gardens and ex situ seed banks provide a buffer against total loss of redundancy and extinction.

We now believe we have a better understanding of the species’ life history (Section 2.5), biological needs (Section 3), and threats (Section 6) compared to when the species was listed in 2001. Because the species does not occur under natural conditions, the status of the species is dependent upon land use, land management, and future reintroductions (Section 9). The result is a species that is conservation reliant with moderate resiliency (with continued management), low representation, and low redundancy that is at constant threat of extinction should management cease to occur. The long-term persistence of this species is dependent upon the level of effort that is directed towards creating and maintaining suitable habitat. The difficulty of maintaining suitable habitat will be exacerbated by the effects of climate change, the lack of adequate management resources, and available land.

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