Soil Ecology and Research Group last update August 5, 2003

ANNUAL REPORT

HABITAT RESTORATION IN SUPPORT OF THE SAN CLEMENTE ISLAND LOGGERHEAD SHRIKE PROGRAM

Introduction
This report describes the activities and accomplishments of the San Clemente Island Native Habitat Restoration Program from January 2002 through December 2003. The goals of this program are to ensure the long-term viability of island species through the restoration of native plant communities and to increase the understanding that functioning ecosystems ensure the long-term success of SCI Naval operations. These activities have been conducted for the United States Navy, under contract, by the Soil Ecology and Restoration Group (SERG) of San Diego State University. Tasks identified as critical to the success of this program include the establishment and maintenance of a native plant nursery and the propagation and outplanting of plants essential for the recovery of endangered animals. Additional contractual obligations include the following tasks:

• Native seed collection and storage
• Establishment of live reference area/living collection
• Establishment of stock for erosion control, landscaping, beautification
• Propagation and outplanting of endangered plants
• Selection of areas for outplanting, implementation of
outplanting efforts, maintenance of records of outplantings
• Provide assistance to other botanical programs on the island such as
noxious weed management, herbarium maintenance, and mapping and
collecting data about plant populations

Specifically, this report will address progress made on the development of the native plant nursery, progress with native seed collection, the status of shrike habitat enhancements and the progress of a number of lesser projects.

Native Plant Nursery
Production
Production has focused on generating plants for shrike habitat enhancement projects and native plant community restoration projects associated with exotic species removal. Table 1 lists all species under propagation and the current nursery inventory is presented in Table 2 (species with fewer than 20 individuals have been omitted for brevity). The total number of plants produced to date, excluding grasses, is approximately 10,000 plants.

This year saw increased success with propagation of Lycium californicum cuttings. Although previous attempts had largely failed, the use of powdered growth hormone and Supersoil as a rooting medium, as well as closer regulation of temperature and moisture levels of the cuttings have produced nearly two hundred plants. Similar attempts to propagate L. brevipes have been largely unsuccessful, though a small number of clones of this species have been produced. New methods of propagation are being investigating.

Table 1.
Species in propagation at nursery

Table 2.
Current nursery inventory.

No success has yet been seen in the propagation of island Lyonothamnus floribundus. Germination tests have show very low seed viability (< 0.05%). Successful tests using non-SCI seed sources have shown propagation methods to be sound.

Several minor pest problems were encountered during this term. In early January, an outbreak of post emergence damping off fungus was responsible for the loss of several dozen seedlings. The symptoms of this pathogen include stunted growth, wilting and a darkened ring at the base of the stem. The fungus was likely introduced through the use of native soil in the transplanting medium. The outbreak was halted by eliminating native soil from the medium and by washing the roots with vitamin B1 during transplanting. Vitamin B1 is useful as it stimulates root growth and reduces plant shock during transplantation. A second, though much less lethal, fungal infection has proven to be more difficult to eliminate, but easy to control. An Ascomycota species (bird's nest fungus) has been found growing in several nursery pots. These fungi can cause damage to nursery plants as the fruiting bodies (ascocarp) crowd-out seedlings in the pots. A dusting of cinnamon over the fungus has been reasonably successful at controlling outbreaks of this species.

In early May, herbivory by common earwigs (Forficula sp.) resulted in damage to many plants and loss of approximately 150 Rhamnus pirifolia seedlings in the greenhouse (Figure 1). Efforts to trap out or to discourage this herbivory using cayenne were ineffective. Limited use of bait (Green Light Snail Slug and Earwig Bait) has controlled the infestation and limited damage to acceptable levels. Common ravens (Corvus corax) were responsible for the loss of several dozen individual plants from the outside bench growing area. The behavior of these birds included general loafing on the benches and the pulling of young plants from their pots. Attempts to haze these birds from the site using an airhorn were unsuccessful. Their behavior was modified by hanging a dead raven in the area for two days. The birds were observed returning to the site briefly and have not returned since. (The dead bird was borrowed from IWS Raptor Research and died of unknown and unrelated causes.)

Figure 1. Earwig damage to Lavatera assurgentiflora glabra at nursery.

Seed Collection and Processing
Seed collection activities have focused on monitoring populations for optimal harvest and increasing the diversity of species in storage and thereby available for propagation. Below average rainfall during the previous year has resulted in limited seed production for most species, but it is likely that sufficient amounts will be available to meet the needs for current projects. A total of five kilograms of seed representing twenty-nine different species were collected (Table 3). Several species were collected for the first time this quarter, including Adenostema fasciculatum and Ambrosia chamissonis. The only source of Prunus lyonii seeds found this season was collected from Mosquito Cove, where coastal moisture was able to support flowering during this year’s drought. Total seed inventory is currently approximately twenty-eight grams representing fifty native species (Appendix 1).

Table 3.
Year 2002 Native Seed Collections

Native Species Plantings
Shrike Habitat
Eight native shrub and tree planting sites were completed during 2002. These plantings are primarily intended to enhance shrike habitat quality by increasing the diversity and abundance of native vegetation and by providing structure and cover for both shrikes and prey species. These plantings also enhance native plant communities both directly and through the production and dispersal of seed at these sites.

Installations were completed at Lemon Tank, Boulders, Vista, Chamish, Maple, Flasher, Tota and Pebble (Figure 2). All sites were selected for plant installation based on their current or potential use as captive shrike release sites and the availability of vehicle access for material transport and access. Species selection for each site was based on the appropriateness of site characteristics (soil, aspect, elevation, existing vegetation, etc.) for available SCI nursery grown plants. A total of approximately 2400 plants were installed at these sites. A summary of species planted at these sites is presented in Table 4. A summary of each planting site is presented in Figures 3-10.

Live Reference Collection
Demonstration plantings have been installed around the Natural Resources Facility and Native Plant Nursery and serve both to educate visitors about the diversity of native plants that exist on San Clemente Island and to beautify the facility. These plantings also include a demonstration of the temporary irrigation system typical of habitat enhancement plantings on SCI, as well as tree and shrub plantings added to the courtyard area (Figure 11). Facility plantings now include examples of all species currently in nursery production.

Endangered Species Propagation
Efforts to begin the propagation and outplanting of endangered species have been hindered by delays in the endangered species permit process. Permit applications have now been approved by the U. S. Fish and Wildlife Service and work has begun on the collection of seed and germination of endangered species found throughout the island.

Rare Species Propagation and Outplanting
Efforts have been to aid the reproduction of several plant species, which for various reasons are currently suffering reduced reproductive success. The term “rare species” is not meant to carry any legal definition in this usage and may include any species for which distribution and/or reproduction is limited. Three species of particular interest are Lavatera assurgentiflora glabra, Coreopsis gigantea, and Quercus tomentella. Nursery propagation of these species has been very successful and relatively large numbers of each have been included at several of the planting sites.

Figure 2. Native shrub and tree planting sites completed as of 31 December 2002.

Table 4.
Summary of species planted at 2002 sites

Figure 3. Lemon Tank Native Habitat Restoration Site

Site Summary
Name: Lemon Tank
Utm: 359 267, 3 644 590
Elevation: 1140 feet
Completion date: 24 January 02
Description: The site immediately east of the Lemon Tank dam. The open terrace adjacent to the canyon native and exotic grassland species and Bacharris pilularis. Canyon slopes support primarily native and exotic grassland species, Calystegia macrostegia, Eriophyllum nevinii, Hemizonia clementina and Opuntia littoralis. Mixed species plantings were installed along the terraces and extending down the southern and western slopes of the canyon. A group of sixteen Quercus tomentella were planted on the canyon bottom in an area cleared of Calystegia.
Dominant species: Bromus sps., Nassella pulchra. Calystegia macrostegia,
Notable species: Jepsonia malvaflora and Viola pendunculata are common on the southern slopes.
Quantities planted: Total - 350. Artemisia californica - 83, Ceanothus megacarpus - 14, Encelia californica - 43, Eriophyllum nevinii - 41, Hazardia cana - 7, Heteromeles arbutifolia - 45, Isomeris arborea - 45, Isocoma menziesii - 2, Munzothamnus blairii - 9, Prunus lyonii - 33, Quercus tomentella - 16, Rhus integrifolia - 12
Survivorship: 93%

Figure 4. Vista Native Habitat Restoration Site

Site Summary
Name: Vista
Utm: 364 863, 3 639 013
Elevation: 1936 feet
Completion date: 4 March 02
Description: This site is located at the end of the dirt road between the Vista Radio and FACSFAC facilities. The site is characterized by open east facing slopes supporting native and exotic grassland species and three small Quercus tomentella groves. Soils are loose and friable with a large proportion of rock. Plantings are up-slope and to the north and south of the groves.
Dominant species: Quercus tomentella, Bacharris pilularis, Artemisia californica, Mimulus aurantiacus, Nassella pulchra, Avena fatua, Bromus hordeeaceus, B. diandrus, B. madritensis.
Quantities planted: Total - 242. Artemisia californica - 29, Ceanothus megacarpus - 11, Eriophyllum nevinii - 26, Hazardia cana - 22, Heteromeles arbutifolia - 43, Munzothamnus blairii - 4, Quercus tomentella - 96, Rhus integrifolia - 11
Survivorship: 83%

Figure 5. Boulders Native Habitat Restoration Site

Site Summary
Name: Boulders
Utm: 363 160, 3 640 745
Elevation:
Completion date: 11 April 02
Description: The site is located approximately 0.1 east of Ridge Road near the Boulders camera pad. Site vegetation is characterized by native and exotic grassland species and sparse native shrubs. Soils are loamy clays with considerable rock. Plantings were installed on a small bench terrace and east facing slope just below the ridge.
Dominant species: Nassella pulchra, Avena fatua, Bromus hordeeaceus, B. diandrus, B. madritensis.
Quantities planted: Total - 218. Artemisia californica - 20, Ceanothus megacarpus - 3, Eriophyllum nevinii - 19, Hazardia cana - 11, Heteromeles arbutifolia - 31, Munzothamnus blairii - 4, Quercus tomentella - 108, Rhus integrifolia - 28
Survivorship: 83%

Figure 6. Chamish Native Habitat Restoration Site

Site Summary
Name: Chamish
Utm: 357 410, 3 647 208
Elevation: 872 feet
Completion date: 21 June 02
Description: The site is located east of the VC-3 and near an abandoned reservoir. Soils are sandy clays. Terrace vegetation is dominated by exotic annual grasses and exotic shrubs. Canyon areas are dominated by Rhus integrifolia, Opuntia littoralis, Salsola tragus and Calystegia macrostegia. Three planting areas were selected on the exotic grass dominated terrace. One area was selected south of the dam, one north of the dam and a third (not shown on map do to scale limitations) was selected on the north side of Chamish Canyon and east of the landfill. The later site was selected for species focused plantings of Lavatera assurgentiflora and Coreopsis gigantea.
Dominant species: Rhus integrifolia, Opuntia littoralis, Avena fatua, Bromus hordeeaceus, B. diandrus, B. madritensis, Atriplex semibacata, Salsola tragus, Calystegia macrostegia, Lotus argophyllus.
Quantities planted: Total - 327. Artemisia californica - 26, Coreopsis gigantea - 27, Encelia californica - 34, Eriophyllum nevinii - 28, Hazardia cana - 27, Heteromeles arbutifolia - 9, Isomeris arborea - 22, Isocoma menziesii - 42, Lavatera assurgentiflora - 63, Malosma laurina - 2, Munzothamnus blairii - 23, Rhus integrifolia - 24
Survivorship: 98%

Figure 7. Maple Native Habitat Restoration Site

Site Summary
Name: Maple
Utm: 356 440, 3 649 395
Elevation: 440 feet
Completion date: 16 June 02
Description: The site is located just south of the gate on Nots Road. Soils are loamy clay. Existing vegetation includes native and exotic grasslands, and maritime desert scrub lycium phase. Plantings were installed along the terraces and adjacent the canyon.
Dominant species: Opuntia littoralis, O. prolifera, Nassella pulchra, Avena fatua, Bromus hordeeaceus, B. diandrus, B. madritensis, Atriplex semibacata, Salsola tragus, Lycium californicum, Hemizonia clementina, Rhus integrifolia
Quantities planted: Total - 339. Artemisia nesiotica - 29, Encelia californica - 24, Epilobium canum - 4, Eriogonum giganteum - 15, Eriophyllum nevinii - 27, Galvezia speciosa - 16, Hazardia cana - 27, Heteromeles arbutifolia - 40, Isomeris arborea - 15, Isocoma menziesii - 26, Lavatera assurgentiflora - 36, Malosma laurina - 4, Munzothamnus blairii - 26, Prunus lyonii - 20, Rhus integrifolia - 30
Survivorship: 97%

Figure 8. Flasher Native Habitat Restoration Site

Site Summary
Name: Flasher
Utm: 354 428, 3 650 573
Elevation: 782 feet
Completion date: 19 August 02
Description: The site is located approximately 0.1 miles west of Ridge Road just north of the Photo Lab. Site vegetation is characterized by exotic grassland species and sparse native subshrubs. Soils are loamy clays. Plantings were installed along small drainages, mainly on north-facing slopes. Plantings at this site included three Maritime Desert Scrub species utilizied for the first time in SCI outplantings: Astragalus nevinii, Lycium californicum, and Lotus argophyllus argenteus
Dominant species: Calystegia macrostegia, Atriplex semibaccata, Opuntia littoralis, Lycium californicum, Avena fatua.
Quantities planted: Total - 270. Artemisia californica - 28, Astragalus nevinii – 8, Coreopsis gigantea – 2, Encelia californica - 13, Epilobium canum – 3, Eriophyllum nevinii - 14, Galvezia speciosa – 1, Hazardia cana - 24, Heteromeles arbutifolia - 28, Isomeris arborea – 21, Isocoma menziesii – 24, Lavatera assurgentiflora – 7, Lotus argophyllus argenteus – 21, Lycium californicum – 2, Munzothamnus blairii - 4, Prunus lyonii - 21, Rhus integrifolia – 36.
Survivorship: 98%

Figure 9. Tota Native Habitat Restoration Site

Site Summary
Name: Tota
Utm: 360 012, 3 643 843
Elevation: 1402 feet
Completion date: 25 August 02
Description: The site is located approximately 0.6 miles east of Ridge Road along Tota Road. Site vegetation is characterized by native grassland species and native shrubs. Soils are loamy clays with considerable rock. The site may be characterized as an early successional shrubland and has become dominated in recent years by the rapidly increasing presence of Baccharis pilularis. Plantings at this site were weighted to increase species diversity of this shrubland. Plantings were installed on the south side of Tota Canyon, primarily on open flats and along small dainages.
Dominant species: Nassella pulchra, Avena fatua, Baccharis pilularis, Opuntia littoralis.
Quantities planted: Total – 345. Artemisia californica - 37, Ceanothus megacarpus - 34, Epilobium canum – 21, Eriogonum giganteum – 27, Eriophyllum confertiflorum – 7, Eriophyllum nevinii - 31, Galvezia speciosa – 1, Hazardia cana - 25, Heteromeles arbutifolia - 61, Isomeris arborea – 11, Lotus argophyllus argentea - 2, Mimulus aurantiacus - 2, Munzothamnus blairii - 25, Prunus lyonii - 17, Rhus integrifolia – 38, Rhamnus pirifolia - 4.
Survivorship: 98%

Figure 10. Pebble Native Habitat Restoration Site

Site Summary
Name: Pebble
Utm: 360 012, 3 643 843
Elevation: 1402 feet
Completion date: 14 December 2002
Description: The site is located approximately 0.5 miles west of Ridge Road along Bluff Road. Site vegetation is characterized by native grassland species and native shrubs. Soils are loamy clays with considerable rock. Plantings were installed along drainage on the north side of Bluff Road and on open terrace along the south side of Bluff Road.
Dominant species: Nassella pulchra, Avena fatua, Baccharis pilularis, Opuntia littoralis.
Quantities planted: Total – 311. Artemisia californica - 27, Ceanothus megacarpus - 28, Epilobium canum – 17, Eriogonum giganteum – 27, Eriophyllum confertiflorum – 2, Eriophyllum nevinii - 34, Galvezia speciosa – 10, Hazardia cana - 24, Heteromeles arbutifolia - 39, Isomeris arborea – 25, Lotus argophyllus - 4, Mimulus aurantiacus - 2, Munzothamnus blairii - 20, Prunus lyonii - 11, Rhus integrifolia – 33, Rhamnus pirifolia 8.
Survivorship: 100%

Figure 11. Map of live reference collection plantings.

Lavatera assurgentiflora glabra is a taxa found only on San Clemente and Santa Catalina Islands. Two very small populations exist on Santa Catalina, while seven populations of Lavatera assurgentiflora glabra comprising less than 100 total individuals are known on San Clemente (excluding those found as landscaping in Wilson Cove). The inclusion of 113 Lavatera at planting sites Chamish, Flasher and Maple has doubled the number of individuals known outside the Wilson Cove area (Figure 12). Coreopsis gigantea is a taxa known from only one location on San Clemente. Thirty-four individuals were included at sites Chamish and Flasher. Very little natural recruitment has been observed for Quercus tomentella on SCI. This species is endemic to the Channel Islands and Guadelupe Island. A total of 204 Quercus tomentella seedlings were included in the plantings at sites Vista and Boulders.

Figure 12. Lavatera assurgentiflora glabra individual at the Chamish planting site.

Island Beautification
To increase interest and pride in the native flora, an installation of surplus native plants was made adjacent to the "San Clemente National Forest" sign along Ridge Road. This sign dates to the early 1970's, when it was erected to celebrate a small grove of eucalyptus trees. These trees were removed in the 1980’s during a campaign to eradicate exotic species from the island. The sign has since been considered by many to be an ironic joke welcoming passers-by to a landscape dominated by exotic annual grasses. Few residents and visitors are aware that any native trees exist on San Clemente Island. In an effort to alter this misconception, twenty individuals of native tree and shrub species have been planted at this site. Additional plantings at this site are expected for the future. A similar installation is being planned for the SCI air terminal. Surplus nursery stock has also been provided to various Navy tenant commands, including SPECWAR/MarOps, BUDS and SeaBees, for barracks and facility landscape improvements. Approximately 150 surplus plants were provided for such projects in 2002.

Figure 13. Map of San Clemente National Forest plantings.

Planting Methods
Planting sites were prepared by first clearing a continuous strip approximately 1.5 - 2.0 meters wide through vegetation and duff with a gas powered string trimmer. These clearings facilitate the installation of irrigation lines and reduce resource competition for plantings. Planting holes were dug at approximately 2-3 meter intervals in the center of the cleared strip. Digging was done primarily with hand tools including seventeen-pound dig bars, post-hole diggers and hand trowels. Following excavation, irrigation tubing was stretched the length of the clearing and drip emitters were installed at each planting hole.

Prior to planting, each hole received approximately 1-2 gallons of water via the irrigation system. After the water was allowed to percolate, plants were installed in each hole and a shallow berm of approximately 0.5 meters was constructed around each plant to retain irrigation water. After installation, each plant received an additional 1-2 gallons of water.

Site Maintenance
All plantings were maintained with supplemental watering. Supplemental water is intended to sustain the plants during the drought season and will be discontinued once the soils have hydrated from the winter rains. Water was applied on a 2-3 week schedule, by means of a 180 gallon truck mounted water tank fitted with an electric water pump and portable generator Figure 14. Each plant received an average of 2.5 gallons of water per month. Watering dates and volumes are included in Appendix 2.

Figure 14. Truck fitted with 180-gallon water tank.

As the number of outplanting sites increased during 2002, watering events dominated the work schedule. Figure 15 represents field days that included at least one watering event. The minimum time required for a single delivery of 180 gallons is approximately 2.5 hours. Plans are underway to increase the amount of water that can delivered in a single trip in order to increase efficiency and facilitate the expansion of planting sites.

Figure 15. Summary of watering events.
(Shaded blocks represent days with watering events.)

Survivorship and Growth
During each watering event, irrigation lines were inspected for proper operation and survivorship data were recorded by species. Table 5 represents a summary of survivorship at each site across all species. Table 6 represents survivorship for each species across all sites. Growth data were collected quarterly for a subset of all plantings.

Table 5.
Summary of outplanting survivorship

Table 6.
Summary of outplanting survivorship by species

Measurements of height for Quercus tomentella plantings and height and width for all other plantings have been collected and are currently being prepared for publishing.