Malibu Lagoon Restoration Project Results of surveys: Amphibians, Reptiles, Terrestrial Invertebrates

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1 FH & A (661) ; fax; fthovore@thevine.net Frank Hovore & Associates Sundance Place Santa Clarita, CA August 2005 Malibu Lagoon Restoration Project Results of surveys: Amphibians, Reptiles, Terrestrial Invertebrates Terrestrial Invertebrate Surveys Background Terrestrial invertebrate diversity within any given area of limited extent, such as the Malibu Lagoon restoration area, is determined by floral diversity, combined with edaphic conditions and factors of human disturbance. The existing conditions at the lagoon consist of the following segments: a lawn and parking area, surrounded by native and non-native species in marginal hedge formations; uplands around the mouth of the creek and side channels, much of which has been heavily invaded by ornamental species from adjacent development; stepping-stone patches of deposited materials forming a walkway network between the lawn area and beach, vegetated with a low-diversity mixture of native and non-native species; a small patch of dune strand at the terminus of the walkway system, heavily impacted by use as an outdoor toilet by beach-goers and transients; small areas of coastal salt marsh scrub, heavily invaded by ruderal elements; open mudflats along channel banks and inside the creek channel mouth; open beach sand. Areas which have largely been altered from their original substrate characteristics, or which have been heavily compacted due to foot traffic and vehicle use, generally exhibit much lower native terrestrial diversity than do even remnant areas of intact substrates. And, areas which have been converted from native to non-native vegetation, or in which native vegetation occurs only as landscaping (without natural spacing and understory characteristics) also may lose a high percentage of original species diversity. Further, where non-native plant species predominate, or where disturbance has resulted in floral homogeneity, natural diversity may be replaced by high densities of one or two arthropod species, often non-native. Methodologies

2 Vegetation within the project site was surveyed visually and by foliagedisturbance to census non-fossorial terrestrial arthropods. Burrowing species were surveyed by sifting sand and detritus layers from within the dune and beach formations. Open freshwater was sampled by seine-netting and dip-netting. Open beach strand was sampled visually and by aerial netting. Protocols for foliage censusing were as follows: each of the dominant native plant species present within the survey area were sampled quantitatively using a 1 meter square sampling sheet, the number of samples from each species commensurate with its physical stature and dominance within the flora. Samples taken were: arroyo willow (18 sq. m.); laurel sumac (13 sq. m.); quail bush (8 sq. m.); coyote brush (6 sq. m.); mulefat baccharis (6 sq. m.); St. Catherine s lace (4 sq. m.); giant coreopsis (4 sq. m.); showy island snapdragon (2 sq. m.); and beach bur (2 sq. m.). Non-native species and ornamental plantings were not sampled, although it is recognized that some of the species surveyed are naturalized on the site. Sifting samples were taken within the area of disturbed coastal dunes at the terminus of the access trail to the beach, and on the southern margin of the creek channel. Samples were taken in units of approximately 10 cu. cm. each (roughly corresponding to the sifter volume), and a total of 10 such sifter-samples was taken from beneath beach bur, sand verbena, quail bush, and hottentot fig (non-native). Surveys were conducted on 02 and 20 June, 2005, the overall timing ranging from 10 a.m. through 3:30 p.m. Nocturnal collecting was not conducted in the park because of constraints imposed by other uses of the area, safety concerns, and the effects of adjacent lighting upon UV attractiveness. In order to assess the potential elements present on the site, FH&A reviewed data and specimens one continuous year of malaise trap, sand sifting, and blacklight trapping at the El Segundo Dunes, and also conducted focused invertebrate surveys at Ballona Wetlands, on the Del Rey dunes, and has received all data from the Los Angeles County Natural History Museum El Segundo dune studies (R. Mattoni, pers. comm.). Additionally 14-year study of the nocturnal insect fauna of Malibu, conducted at two nearby sites facing the coastline (Charmlee Natural Area, F.T. Hovore, M. Kouba; private residence at 4244 Avenida de la Encinal, P. & S. Russell), plus two seasons of light trapping at the Malibu Canyon CDF station, and at a private residence on Decker Canyon Road (I.P. Swift, F.T. Hovore) provided abundant local material for assessment, and is incorporated herein as appropriate. Results of surveys A total of 96 terrestrial invertebrate species were segregated during the visual searching, meter plot and sifting surveys. Most occurred as single or occasional captures, but some species, such as Argentine ants (Linepithema humile), willow aphids (Pterochloris viminalis) and chironomid midges (Chironomidae) were abundant beyond counting. The captures may be summarized as follows (common names generally follow Hogue, C.L., 1993, Insects of the Los Angeles Basin; Powell, J.A. and Hogue, C.L., 1979, California insects; Mattoni, R., 1990, Butterflies of greater Los Angeles).

3 Collembola (springtails): 1 species, indet. Zygentoma (silverfish): 1 species, indet. Ephemeroptera (mayflies): 1 species (Baetis sp.) Odonata (dragonflies, damselflies): 4 spp., including green darner (Anax junius); multicolored darner (Aeschna multicolor); red-tinged skimmer (Sympetrum illotum); 2 species of damselfly, including violet dancer (Argia vivida). Dermaptera (earwigs): 1 sp., ring-legged earwig (Euborellia annulipes). Orthoptera (grasshoppers and allies): 2 spp., field cricket (Gryllus sp.); forktailed bush katydid (Scudderia mexicana). Psocoptera (booklice): 1 sp., indet. Hemiptera (true bugs): 3 spp., green stinkbug (Chlorochroa sp., prob. uhleri), [nymphs only]; squash bug (Anasa tristis); marsh boatman (Trichocorixa reticulata) [abundant in slough]. Homoptera (homopterans): 3 spp., willow leafhopper (Cicadellidae); gray treehopper (Membracidae); willow aphid (Pterochloris viminalis). Neuroptera (nerve-winged insects): 3 spp., snakefly (Argulla sp.); green lacewing (Chrysoperla sp., prob. plorabunda); antlion sp. indet. (Mymeleontidae). Lepidoptera (butterflies and moths) 12 spp.,: looper noctuids (3 different species, undeterminable from caterpillars); measuring moths (2 species, caterpillars only); brown ctenucha (Ctenucha brunnea); western tiger swallowtail (Papilio rutulus); cabbage white (Pieris rapae); common white (Pieris protodice); pygmy blue (Brephidium exilis); fiery skipper (Hylephila phyleus); funereal duskywing (Erynnis funeralis). Diptera (flies), 12 spp.,: cranefly sp. indet (Tipulidae); mosquito (Culex sp., prob. peus); water midge (Chironomidae); flower fly (Syrphidae); beeflies (Bombyliidae, 2 spp., indet); house fly (Musca domestica); stable fly (prob. Stomoxys calcitrans); green bottle fly (Phaenicia sericata); fruit fly (Drosophila melanogaster, in trash cans); kelp fly (Coelopa vanduzeei); and brine fly (Ephydra riparia). Coleoptera (beetles), 26 spp.: Oregon tiger beetle (Cicindela oregona); ground beetle (prob. Agonum funebre); water scavenger, indet. (Hydrophilidae); click beetles (3 spp., indet); common sand beetle (Coelus ciliatus) and one indet. small darkling beetle (Tenebrionidae); hister beetle (Histeridae); ladybird beetles

4 (Hippodamia convergens, Adalia bipunctata, 1 sp. indet); brown leatherwing (Cantharis consors); minute sand scarab (Psammodius mcclayi); branch borers (Psoa maculata, 1 sp. indet.); willow girdler (Agrilus angelicus); spider longhorn (Ipochus fasciatus); cucumber beetle (Diabrotica sp. and 2 other spp. of Chrysomelidae, indet.); 5 species of weevils, including broad-nosed weevils and Curculio spp., all indet (Curculionidae). Hymenoptera (ants, bees and wasps): 7 spp.: Argentine ant (Linepithema humile); willow leafgall sawfly (Euura pacifica); yellowjacket (Vespula pensylvanica); golden paper wasp (Polistes fuscatus aurifer); carpenter bee (Xylocopa varipuncta); honeybee (Apis mellifera); tiphiid wasp (Tiphiidae). Arachnids (spiders and their allies): 10 species: black widow (Latrodectus hesperus), 5 species of jumping spider (Salticidae), 3 species of crab spider (Thomosidae), golden orb weaver (Argiope aurantia); red spider mites (Tetranychidae), 1 sp. indet. Non-insect arthropods: Crustacea: dooryard sowbug (Porcellio laevis), common pillbug (Armadillidium vulgare); amphipod (Amphipoda); brown garden snail (Helix aspersa). Species observed, detected from evidence (pupal casings, larval workings, fragments of exoskeletons, etc.) included several additional undetermined species of darkling beetle (Tenebrionidae); at least 5 species of smaller Diptera (undeterminable); common mud-dauber (Sceliphron caementarium); hornet moth (Synanthodon robiniae, in willow); and tiger moth (Arachnis picta). Additional, mostly nocturnal, species expected to occur within the upland terrestrial habitats of the park, based upon collection records within 5 miles of the site in similar vegetation and habitat formations, include the following (many without common names): beetles: Serica spp., Dichelonyx spp., Parathyce palpalis, Phymatodes lecontei, and willow flat-headed borer, Dicerca hornii; moths: Acontia spp., Apame cuculliformis, Apantesis hewletti, Catabena sagittata, Cisthene spp., Digrammia spp., Euxoa infausta, Hemihyalea edwardsii, Lacinipolia spp., Melipotis spp., Polia sp., Schinia buta, Synedoida edwardsi, Zale termina (some moth records from the California Moth Specimens Database project, U.C. Berkeley). A number of agency-listed sensitive arthropod species occur within the coastal portion of the Santa Monica Mountains, including Trask s shoulderband snail, wandering (salt marsh) skipper butterfly, Busck s gall moth, Belkin s dune tabanid, globose dune beetle, dorothy s dune weevil, Santa Monica Mountains shieldback katydid, and sandy beach tiger beetle. Huffman (2002, Santa Monica Bay Audubon Soc. newsletter, Vol. 26(1), reports seeing wandering (salt marsh) skipper (Panoquina errans) at Malibu Lagoon, and while this record remains to be verified by further detection, the species may occasionally wander into the area, wherever the host plants (Distichlis spicata and other grasses) are present.

5 The other species likely would not occur within the project area, primarily because the natural, native habitat values are either lacking or retorted and degraded, or their specific host plants or substrate associations are lacking. Habitat values are not present for the tabanid fly, globose dune beetle, or sandy beach tiger beetle, all of which are found in specific dune substrates or on undisturbed beach strand. The first two species persist in low numbers locally only in the least-disturbed portions of the El Segundo (LAX) dunes, adjacent to the El Segundo blue butterfly preserve. The nearest extant population of the tiger beetle known to us is at Atascadero State Beach. Dorothy s dune weevil is more widespread than the other species, and does occur in remnant dune areas in Playa del Rey (where it is easily detected by sifting) but no evidence of it was seen during the sifting surveys. The shieldback katydid is an upland chaparral species which has been taken feeding on iceplant along residential roadsides near Big Rock, and Trask s shoulderband is a dune species often common on the El Segundo dunes under piles of removed iceplant, suggesting that these two species have shifted from native substrates and hosts onto introduced resources. No evidence of either species was found in focused surveys, though, and they do not appear to be present. Herpetofaunal surveys Malibu Creek has sustained perennial flows, and therefore native amphibians and aquatic reptiles may have persisted within the creek and upper portion of the lagoon, above the limit of brackish or saline water. Existing conditions of disturbance, water quality, and episodic high-energy flows preclude species with narrowly specialized biological or ecological needs, but ecological generalist taxa such as western toad (Bufo boreas halophilus) and Pacific chorus frog (Pseudacris regilla) might yet persist within the area. Both of these species have higher tolerances for salinity or pollution than do most amphibians, and persist in rural residential areas adjacent to creeks and ponds, where landscaping and artificial ponds provide suitable moisture and breeding sites. There is at best a very low probability that two-striped garter snake and southwestern pond turtle occur in the creek within the zone of potential project effects. The upland terrestrial portions of the site-- not the salt marsh systems-- support a suite of common, human-tolerant (or resistant) species of lizards, and perhaps also a few snakes, but overall, the herpetofauna diversity appears to have been reduced by adverse interactions with humans using the area. Methodologies Amphibians were searched-for visually, by dip-netting, and by turning over debris and other objects within the riparian zone. Reptiles were observed during diurnal fieldwork. Two transients living within the area were asked if they ever see snakes, and none of them had seen any within the project area (and both indicated that they would kill any snake they encountered). Crew monitors working on the removal of exotic plants along Malibu Creek from the park boundary inland were interviewed for sight records of

6 reptiles and amphibians. Additionally, literature sources-- including records from the Los Angeles County Natural History Museum-- were consulted for historic data. Results of surveys The retorted amphibian fauna of the lower portion of Malibu Creek, where it reaches into the project zone of potential impacts, consists of at most two common generalist species, western toad and Pacific chorus frog. California chorus frog (P. cadaverina) has been found in lower Malibu Creek (De Lisle et al., 1986, The distribution and present status of the herpetofauna of the Santa Monica Mountains, Spec. Publ. 2, Southwestern Herpetologists Soc.; various studies by L. Kats and students, Pepperdine University, on-line). It generally does not appear to be as tolerant of disturbance, water pollution and elevated salinity as are the other two species, and we found no evidence to suggest that it has persisted in the creek at or below the point of PCH crossing. Physical and chemical characteristics of the creek channels within the project area are wholly unsuited to use by coast range newt (Taricha t. torosa). This species persists in scattered metapopulations within the upper portions of several drainages on the coastal slope of the SMMTs, but has suffered declines due to a variety of anthropogenic effects, including introduced predators (crayfish), changes to creek morphology, roadkill mortality, and post-fire creekbed siltation. It occurred historically within lower Malibu Creek (De Lisle et al., 1986, ibid), and may persist within Malibu Canyon where it passes through Malibu Creek State Park. Two terrestrial salamanders, the black-bellied slender salamander (Batrachoseps nigriventris) and Monterey salamander (Ensatina e. eschscholtzii), occur within the Malibu Canyon drainage, and the former is fairly common (but secretive) in disturbed settings with moist substrates and dense overstory shading. It might persist within residential areas along Malibu Creek above PCH bridge, and perhaps even in the dense laurel sumac understory around the parking lot and in the willow scrub. There is little probability that the larger, more-conspicuous Monterey salamander occurs anywhere within the site vicinity. No other native amphibians would be present within Malibu Creek or around its banks within the proposed project area of effects. Lizard species present and relatively common throughout the less-disturbed portions of the study area include side-blotched lizard (Uta stansburiana elegans) and western fence lizard (Sceloporus occidentalis longipes). The former species occurs along the paths and around the margin of the beach walkway interface, wherever loose sands and cover provide habitat values; the latter is most common along the pathway to the beach, where it frequents the bridge pilings and rails. These two species are abundant throughout Southern California, and their tolerance for human disturbance combined with successful breeding rates has permitted them to persist within urban residential areas, vacant lots, parks, and even roadway medians. Perhaps more interesting is that fence lizards are common in the wrack and debris in the degraded marsh habitats and around

7 the beach margin. This is not typical habitat for the species, and suggests that the remnant marsh grassland system is functionally transitioning from a salt marsh environment to an upland system. This same phenomenon was observed in the Ballona wetlands, (F. Hovore, 1989, field studies, and 1991, Ballona wetlands/playa Vista DEIR, Biota: Amphibians, Reptiles and Mammals) where-- in the absence of tidal flushing-- salt marsh habitat was transitioning from saline soils and halophytic plants to ruderal upland taxa. Also likely present, but more restricted in distribution on the site, would be San Diego alligator lizard (Elgaria multicarinatus webbi), western skink (Eumeces s. skiltonianus), and possibly also silvery legless lizard (Aniella p. pulchra). Within riparian systems, the first two species typically occur where there is dense undergrowth and accumulated debris; the hedge-like stand of laurel sumac around the parking lot, and the dense willow scrub near the PCH bridge appear most suitable to their use. Legless lizards are much commoner than historic accounts would indicate (De Lisle et al., 1986, ibid, list only 7 localities in the Santa Monica Mountains), but their fossorial, secretive behavior makes them difficult to census. If the species occurs within the project area, it would most likely be in areas of loamy soils with dense cover (such as the willow scrub near the bridge) and in the vegetated areas of remnant dune sand. The only snakes likely to occur within the lower portion of Malibu Creek as it approaches and passes under PCH bridge would be those which are so abundant and widespread within the coastal slope of the SMMTs that they are able to continuously recolonize sink areas such as the park. The species most likely to occur are San Diego gopher snake (Pituophis catenifer annectens) and California kingsnake (Lampropeltis getula californiae), both of which are common in other disturbed coastal lowlands and degraded/invaded salt marsh habitats (such as Ballona Creek). Small individuals of either species might persist within the dense understory of the riparian scrub. Much less-likely to occur in the park are southern Pacific rattlesnake (Crotalus oreganus helleri), San Bernardino ringnecked snake (Diadophis punctatus modestus), and two-striped garter snake (Thamnophis hammondi). These species undoubtedly occurred within the lower portion of Malibu Creek, in the site vicinity, but existing conditions are such that none of them likely would be able to maintain a viable metapopulation anywhere within the area of human impacts. The only snake species observed during exotic vegetation removal along Malibu Creek (Summer, 2005, J. Pucci, pers. comm.) were two southern Pacific rattlesnakes. Summary and comments Most of the arthropod and herpetofaunal species found at the Malibu Lagoon restoration site are associated with upland scrub and freshwater riparian habitats. The highest invertebrate species diversity was found on laurel sumac, willow and coyote brush; the lowest was in the coastal scrub and dune habitats. Species found on the laurel sumac were entirely common upland taxa, some of which are found on other host plants and range over most of the coastal slope of southern California and northern Baja, Mexico. Species associated with willow typically occur with this host within most

8 coastal riparian systems, and sometimes inland into middle-elevation stream systems. The bostrichid beetle, Psoa maculata, occurs to 6,000 feet in the San Gabriel range, and Ipochus fasciatus, despite being flightless, utilizes over 14 recorded host plant genera and occurs from coastal central Baja to Santa Cruz, and inland to San Bernardino County. Similarly, the native invertebrates found in the remnant coastal sand deposits are some of the most common and widespread dune taxa in California, occurring almost anywhere that coastal dune formations persist. Habitat values are not present for the globose dune beetle (which is restricted to a few small populations in sheltered beach dunes, including LAX dunes and near Goleta Beach), or sandy beach tiger beetle, which occurs commonly on beaches which receive minimal human use (such as at Atascadero State Beach), but is extirpated by heavy foot traffic and vehicles. The presence of terrestrial, non-aquatic reptiles within the small marsh patches suggests that the salt marsh habitat characteristics are transitioning to upland values. High numbers of fence lizards in the marsh, for example, is indicative of degraded habitat conditions; this species would not normally occur within a viable, tidally flushed salt marsh system. Restoration of the salt marsh habitat system, then, would promote higher densities of native coastal marshland and dune scrub species, and perhaps permit colonization and metapopulation establishment of rare species such as wandering skipper and globose dune beetle. Removal of the existing park area and upland terrestrial habitats, including the small area of willow scrub, would not constitute an adverse, significant impact to any known listed species of arthropod, amphibian or reptile. The species present all are common and widespread throughout similar habitat types within the coastal zone and slope of southern California, and most range widely beyond this region. During removal of the systems present, any amphibians or reptiles observed should be captured and transported to suitable habitat areas outside of the zone of direct impacts. In particular, if any snakes should be found, they may be removed to safer habitat areas further up Malibu Creek, within the parklands. Respectfully submitted,

9 Frank T. Hovore, Principal biologist Sensitive Species Surveys EIR and EIS Biological Assessments HCP and NCCP Planning Mitigation Monitoring Parks and Recreation Planning Environmental Education

Key 1 Key to Insects Orders

Key 1 Key to Insects Orders Notes: This key covers insect orders commonly and occasionally observed. However, it does not include all orders. Key #1 is similar, but easier, being limited to insect orders