Preliminary Insect (Butterfly) Survey at Griffith Park, Los Angeles, California

Kathy Keane October 30, 2003 Keane Biological Consulting 5546 Parkcrest Street Long Beach, CA 90808 Subject: Preliminary Insect (Butterfly) Survey at Griffith Park, Los Angeles, California. Dear Kathy: Introduction At the request of Keane Biological Consulting (KBC), Guy P. Bruyea (GPB) conducted a reconnaissance-level survey for the butterfly and insect inhabitants of Griffith Park in northwestern Los Angeles County, California. This report presents findings of our survey conducted to assess butterfly and other insect diversity within Griffith Park, and briefly describes the vegetation, topography, and present land use throughout the survey area in an effort to assess the overall quality of the habitat currently present. Additionally, this report describes the butterfly species observed or detected, and identifies butterfly species with potential for occurrence that were not detected during the present survey. All observations were made by GPB during two visits to Griffith Park in June and July 2003. Site Description Griffith Park is generally located at the east end of the Santa Monica Mountains northwest of the City of Los Angeles within Los Angeles County, California. The ± 4100-acre Griffith Park is situated within extensive commercial and residential developments associated with the City of Los Angeles and surrounding areas, and is the largest municipal park and urban wilderness area within the United States. Specifically, Griffith Park is bounded as follows: to the east by the Golden State Freeway (Interstate Highway 5) and the City of Glendale and extensive commercial and residential development beyond; to the north by the Ventura Freeway (SR 134), the City of Burbank and extensive commercial and residential development beyond; to the south by Los Feliz Boulevard, Hollywood Reservoir, Hollywood Freeway (Highway 101), the Cities of Hollywood and Los Angeles and extensive commercial and residential development beyond; and to the west by Universal City, Highway 101, extensive commercial and residential development, and the western portion of the Santa Monica Mountains beyond. Griffith Park is situated within the Rancho Los Feliz land grant and Sections 26, 27, 34, 35, Townships 1N and 1S, Range 14W within the U.S.G.S. Hollywood and Burbank 7.5’ series quadrangle maps. Land use varies within Griffith Park, and includes anthropogenic disturbances such as areas associated with hiking and equestrian trails, paved and unimproved roads, and various commercial developments including the Los Angeles Zoo, Greek Theatre, Griffith Observatory, Los Angeles Equestrian Center, several museums, and public golf courses. Topographically, Griffith Park contains gently to steeply sloping ridgelines and flat areas with a combined maximum vertical relief of roughly 1241 feet between the highest and lowest elevation points. Elevations at Griffith Park range from approximately 384 to 1625 feet above mean sea level (AMSL), with Mt. Hollywood at its peak elevation. Surrounding topographic features include gently to steeply sloping hillsides with canyons and ridgelines interspersed with relatively flat areas in the valleys surrounding Griffith Park. Sensitive Butterfly Species Background Information Although the scope of the present study includes the identification of all potential insect inhabitants of Griffith Park, the present study focused on butterfly diversity within the Park due to survey time constraints and other factors. Butterflies are among the more familiar and easily identified insects to the amateur entomologist or nature enthusiast, and can be a good indicator of habitat quality in a particular area. Many butterfly species are easily monitored and respond quickly to changes in habitat, and their absence (in places where they were formerly present) can be an important indicator of habitat degradation. In that vein, butterfly occupants of Griffith Park are discussed in detail herein. Many butterflies are becoming increasingly scarce in southern California, especially in coastal and valley areas were natural habitats have been converted for human uses or have been adversely impacted by various anthropogenic disturbances. Additionally, in the relatively less disturbed foothill and mountain areas the spread of invasive non-native weedy vegetation, grazing, fire suppression, and off- road vehicle activity is threatening many native plants, including butterfly larval host plants. There are approximately 135 recorded butterfly species from Los Angeles County, of which approximately 120 are considered resident. Some species have adapted well to ornamental landscapes, but many formerly common species have now become increasingly rare over the past few decades due to urban expansion and other factors. Several butterflies presently (and/or historically) found in Los Angeles County (and/or areas of adjacent southern Kern County) are now protected or are considered species of special concern (Table 1 and Sensitive Species Accounts). At least three butterflies that once occurred in Los Angeles County are now presumably extinct. These include, 1) the unsilvered fritillary (Speyeria adiaste atossa), which was last observed near Mt. Pinos in 1959, 2) a very localized race of the Sonoran blue (Philotes sonorensis extinctus) that once occurred in the upper San Gabriel wash above Azusa (to 1968), and 3) the Palos Verdes blue (Glaucopsyche lygdamus palosverdesensis, herein referred to as PVB), which was last observed on the Palos Verdes peninsula in 1983. Three butterflies known from Los Angeles County are now on the federal list of endangered wildlife. These include the El Segundo blue (Euphilotes battoides allyni, herein referred to as ESB1), the Quino checkerspot butterfly (Euphydryas editha quino, herein referred to as QCB), and the PVB. Several other butterflies are considered uncommon in Los Angeles County, some having federal or state status (i.e., species of special concern), and others that warrant careful monitoring due to declining populations or extremely limited ranges within Los Angeles County. These include (but are not limited to) the San Emigdio blue (Plebulina emigdionis), the Santa Monica Mountains hairstreak (Satyrium auretorum fumosum), the wandering skipper (Panoquina errans), and the Tehachapi Mountain silverspot (Speyeria egleis tehachapina). Butterfly species that appear to be declining (or may be extirpated) in Los Angeles County, but remain common in other areas of their respective ranges include the purplish copper (Lycaena helloides), giant copper (Lycaena xanthoides), Columella hairstreak (Strymon columella istapa), southern sylvan hairstreak (Satyrium sylvinus), western tailed blue (Everes amyntula), coastal arrowhead blue (Glaucopsyche piasus sagittigera), California ringlet (Coenonympha tullia californica), and sylvan satyr (Cercyonis sthenele sylvestris). Table 1. Los Angeles County Sensitive (and/or Narrow-endemic) Butterflies Common Name Scientific Name Status Range * Quino Checkerspot Euphydryas editha quino FE N El Segundo Blue Euphilotes battoides allyni FE N Palos Verdes Blue Glaucopsyche lygdamus FE N palosverdesensis Comstock’s Blue Euphilotes battoides comstocki CR N San Emigdio Blue Plebulina emigdionis FSC N Bright Blue Copper Lycaena heteronea clara CR N Cloudy Copper Lycaena arota nubila CR Y San Gabriel Mountain Sonoran Blue Philotes sonorensis extinctus X N Veined Blue Icaricia neurona CR N Green (=Skinner’s) Blue Icaricia lupini chlorina CR N Santa Monica Mountains Hairstreak Satyrium auretorum fumosum FSC Y? Emmel’s Elfin Callophrys mossii hidakupa FSC N Wandering Skipper Panoquina errans FSC N Alkali Skipper Pseudocopaeodes eunus FSC N Tehachapi Mountains Silverspot Speyeria egleis tehachapina FSC N Unsilvered Fritillary Speyeria adiaste atossa X N Monarch Butterfly Danaus plexippus 1 Y *Indicates whether Griffith Park is within known historical and/or extant range of indicated taxon (Y=yes, N=no) FE=Federally endangered, FSC=Federal Species of Concern, X=Presumed extinct (no status), CR=California Rare (narrow endemic) 1 Overwintering (or nesting) sites should be protected, butterfly probably not at risk currently Over the past century, many formerly common butterfly species have been extirpated from Griffith Park and surrounding areas due to habitat fragmentation and other disturbances. Sensitive butterflies considered to have potential for occurrence within Los Angeles County, based on known ranges, the presence of associated vegetation communities, elevations on site, host plant availability within the general vicinity, and other requirements, are discussed in more detail below. Sensitive Butterfly Species Accounts Quino Checkerspot Butterfly (Euphydryas editha quino) The United States Fish and Wildlife Service (Service) added this rare butterfly to the federal list of endangered wildlife in early 1997. The Quino Checkerspot Butterfly (QCB) is a geographic race (subspecies) of Euphydryas editha, whose combined ranges extend from northern Baja California to Canada along the Pacific coast, and east to Colorado (Bauer, 1975). The QCB is presently known to exist only as several, probably isolated, colonies in southwestern Riverside County, southern San Diego County and northern Baja California, Mexico. This butterfly is associated with sparsely vegetated or bare areas usually characterized by clay or cryptobiotic soil deposits that develop a hard crust within southern California sage scrub vegetation communities. Low-growing herbaceous annuals including the QCB’s primary larval host plant, dot-

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