By Georgette Brisson W00006177 9/18/08 Biology 28
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Mission Blue Butterfly
by Georgette Brisson W00006177 9/18/08 Biology 28 Ecology of Golden Gate National Recreation Area Instructor Crima Pogge Mission Blue Butterfly TOC
Mission Blue Butterfly Introduction: The Mission Blue Butterfly is called Icaricia icarioides missionensis. It is a small blue butterfly in the Lycaenidae (Gossame-Wing butterflies) family, the coppers. This butterfly is part of a Subfamily of Blue or Lycaenid (Lycaenie) Butterfly and is a descendent from the Superfamily of Papilionoidea (Plebejus icarioides missionensis). It is native to the San Francisco Bay Area and part of the endangered list. Formerly relatively widespread on the San Francisco and Marin peninsulas in California, the mission blue is now restricted to only a few sites. It inhabits are in Milagra Ridge in Pacifica, Sweeney Ridge in San Bruno, portions of the Marin Headlands (small pockets on Southern Headlands and Fort Baker), Twin Peaks and McClarren Park. Description of Species: The endangered Mission Blue is a small butterfly with a wingspan ranging from about 25 millimeters (1–1½ inch). The adults are about the size of a quarter (21 – 33 mm). In the male of the Mission Blue Butterfly species, its upper wing is light blue or iridescent blue and lavender. The male edges consist of black margins fringed with long white hair-like scales. In males, the ventral surfaces of the wings are whitish with small circular gray or black spots in the areas of the fore and hind wings. These spots form a border on the top outer wings. Adult females on the upper-side of the wings have dark brown wing surfaces or are sometimes marked with iridescent blue basal overlay areas mixed in with the brown. The margins of the wing fringe are very similar to those on the male of the species with a dark black border and are distinguished with white fringe. The underside bodies of both sexes are marked with an array of dark black speckles forming dot patterns. The under-wings of the male are silver grayish, while the female appear silver gray or brownish. The underside edges of the wings of both is off-white with two rows of irregularly shaped black spots forming a Mission Blue Butterfly Food Source The Mission blue butterfly requires the type coastal scrub and grassland habitat found only near the Golden Gate of San Francisco. Lupines grow best in grassland and rocky habitats lacking taller plants that might crowd them out. The lupine food plants occur in low density even within favored natural areas, often clumped in small pockets. Mission blues must often travel many meters to locate their food plants, thus spreading out over the grassland. Mission blue scarcity is partly due to the distribution of its lupine food plants. Lupines are only found in the grasslands and rocky outcrops. Lupines cannot survive in the shade of shrubs such as coyote brush, among forest of oaks and Douglas firs, or in the wet ravines of willows. Lupine - grasslands are very rare habitats on the SF peninsula. This is part of the reason why the population of the Mission Blue is small and it is in the danger of becoming extinct. The Mission Blue Butterflies mainly feed on
Adults also feed on:
Nectar plants include
Host Plant Food Source for Larvae The larvae will only feed on the leaves of the three host perennial lupine plants to lay their eggs, for the nourishment of larvae, and from which adult Mission blues emerge. These plants are native to their habitat and necessary for survival for the Mission Blue. The host plants utilized by the Mission Blue are
“Without the lupine the Mission blue cannot reproduce, and thus cannot survive”. (Arnold 1994) The butterfly's fate is closely tied to that of the three species of lupine as the plants provide food and shelter for the butterfly in its larval stage. Thus, the mission blue's habitat parallels that of the lupine plant species. Host Plant Descriptions (ref 11) L. albifrons, or Silver Lupine, sometimes known as silver bush lupine, is one of the lupine species that acts as the host plant for the larvae and pupae of the mission blue butterfly. It is a small, round shrub, with a woody trunk. A deciduous perennial, the plant takes up about 2 ft (0.61 m) of space and can reach heights of 5 ft (1.5 m) It blooms a light blue to violet flower on 3–12 in stalks. The leaves are a silver color with a feathery texture. The silver lupine has five different varieties, three of which occur only in California, the other two occur in both California and Oregon. The five varieties are: Lupinus albifrons var. albifrons, silver lupine, Lupinus albifrons var. collinus, silver lupine, Lupinus albifrons var. douglasii, Douglas' silver lupine, Lupinus albifrons var. eminens, silver lupine, and Lupinus albifrons var. flumineus, silver lupine.[10] L. formosus or Summer Lupine has been cited as a poisonous plant. Because of its topological status it faces eradication at the hands of cattle farmers as it has been implicated in crooked calf disease, though it is not endangered. This lupine, along with five others, is poisonous from the time it starts growth in the spring until the seedpods shatter in late summer or early fall. However, the younger the plant the more toxic it is. Summer lupine is one of three piperidine alkaloid-containing plants that have poisonous effects on livestock. It, along with poison hemlock (Conium maculatum) and tree tobacco (Nicotiana glauca), induced "multiple congenital contractures (MCC) and palatoschisis in goat kids when their dams were gavaged with the plant during gestation.” The skeletal abnormalities included fixed extension of the carpal, tarsal and fetlock joints, scoliosis, lordosis, torticollis and rib cage problems. The clinical signs of toxicity in sheep, cattle and pigs included, ataxia, in coordination, muscular weakness, prostration and death.[12] Lupinus variicolor is known by several common names including varied lupine, many colored lupine, Lindley's varied lupine and varicolored lupine. Its range is restricted to the northern coastal scrub and coastal prairie in the U.S. state of California. It thrives in elevations between zero and 1,640 ft (500 m) Another member of the Fabaceae family, it is a shrub.Mating using the Host Plant Females lay eggs throughout the mating flight. The eggs are laid singly on leaves, stems, flowers and seedpods of lupine species. Eggs hatch 4-7 days after being deposited. Young larvae feed on the inner tissues of the host plant leaves. After feeding, the small second instar larvae enter diapause in the litter at the base of the host plant. Larvae emerge from diapause and resume feeding the following spring. The mechanisms that start and end diapause are unknown. Third and fourth instar larvae are tended by ants. These instars have well-developed honeydew secreting glands that entice ants into this tending behavior. Pupation occurs in the soil beneath the host plant. One generation of butterflies is produced each year. Colonies are located at sites ranging from 690 to 1,180-foot elevation. Some colonies occur in the fog belt of the coastal range. Coastal chaparral and coastal grasslands dominate the vegetation type where colonies are found. (ref 2)
Eggs and larvae are parasitized by other insects, such as wasps and flies. Rodents prey upon both larvae and pupae, and many pupae die due to desiccation. Trampling of host plants, larvae, and pupae by humans and dogs is also a problem in some areas. (ref 3) Butterfly Habitat Areas The i. missionensis is federally endangered and found in only a few locations. The Mission Blue Butterfly was first collected in 1937 from the Mission District of San Francisco. Today only a small colony is still located on Twin Peaks Remaining populations of Mission blue butterfly are found in only a few locations around California: Marin County, San Mateo County, San Bruno Mountain, and possibly at San Francisco County. Its historical habitat and distribution of the species is restricted to encompassed much of the coastal scrub and grassland habitat of the Northern San Francisco Peninsula and Marin County. Additional oother colonies of butterfly species have been discovered in San Mateo County. The San Francisco County population is substantially reduced from its former size, surviving primarily on the southeast natural remnant. The Twin Peaks and McClaren Park areas are where the species have been sited. Twin peak population was re-discovered in 2001. Currently the numbers appear stable based on monitoring of San Bruno Mountain Habitat Conservation Plan. In the San Francisco Daly City locations, a small colony of the endangered Mission Blue Butterfly resides on the Milagra Ridge in Pacifica. This area and many others are threaded by urban development for the future. The species has been collected from Marin County. The coastal scrubland and grassland the mission blue requires is found only in and around the Golden Gate Bridge area in San Francisco. Small pockets have been sited on the Southern side of Marin Headlands and Fort Baker, a former military installation managed by the National Park Service (NPS). The Marin Headlands is contained in the Golden Gate National Recreation Area, GGNRA (another NPS entity). In San Mateo County, the mission blue now occurs mostly in Northern San Mateo County, the San Bruno Mountain. Other butterfly colonies have been discovered in higher numbers in San Mateo County. Coastal chaparral and coastal grasslands dominate the vegetation type where colonies are found. These colonies are located at sites ranging from 690 to 1,180-foot elevation. Some colonies occur in the fog belt of the coastal range. The majority of the Mission Blue Butterflies in the SF Bay area are found on San Bruno Mountains. Mission Blues are found commonly at elevations around 700 ft (Arnold 1994) vs. other species at higher elevations. They are located primarily on the eastern, north-eastern and southern slopes (Arnold, 1979; Thomas Reid Associates, 1982). The latter hosts the largest population. San Bruno mountains harbor the largest populations of Mission Blue butterflies in the Bay area. There are sightings at Sweeney Ridge in San Bruno. The San Bruno Mountain area has conducted the most extensive studies of the Mission Blue Butterflies and help promote the laws for the endanger species. Population The California local population of the Mission Blue Butterfly (Icaricia icarioides missionensis) resides in several places. It is mainly in the San Bruno Mountains with an estimated quantity at 18,000 adults. The second largest population is in the Marin Headlands, with the exact quantity not recorded yet. The Twin Peaks area holds approximately 500 and the Skyline Ridges support approximately 2,000 adults. The Lycaenidae are the second-largest family of butterflies with about 6000 species worldwide, with the members also called (gossamer-winged butterflies). They constitute about 40% of the known butterfly species. This family is traditionally divided into the subfamilies of the blues (Polyommatinae), the coppers (Lycaeninae), the hairstreaks (Theclinae) and the harvesters (Miletinae). Others include also the (Lipteninae), (Liphyrinae), and (Poritiinae). A few authorities still include the family (Riodinidae) within the (Lycaenidae). The sole member of the subfamily (Styginae) is represented by (Styx infernalis) from the Peruvian Andes. Recent molecular evidence places (Styginae) within the family (Riodinidae). Populations occurring just North and South of the Mission Blue Colonies are partly the common San Francisco Bay Region subspecies, the Pardalis Blue (Icaricia icarioides pardalis). The Mission Blue is usually distinguished from the Pardalis Blue by the lighter underside spotting, the somewhat smaller size, also the presence of some blue on the female wing top surfaces. Time of year for viewing The adult flight season extends from late March to early July, depending on the location and microclimatic conditions. Females lay eggs throughout the mating flight season March to early July. The butterfly can be sighted as early as late March in places like the summit of San Bruno Mountain or the Twin Peaks. They persist well into June when they will be seen perched on a lupine plant or feeding on coastal buckwheat flowers. Day to day for the adult butterfly is mostly spent foraging for nectar, flying, mating and for the females, laying eggs. Nearly equal time is spent between perching, feeding and flying. The adult mission blue lives approximately one week; during this time, the females lay the eggs on the host plant. The complete mission blue butterfly life cycle lasts one year. Endangered Species Act and Studies (ref 3) Legal Protection: The Mission blue was added to the Federal Endangered Species List in 1976, and is protected under the Endangered Species Act. CLASSIFICATION: Endangered Federal Register 41:22044; June 1, 1976Extentive studies of the Mission Blue Butterfly with habbit restoration and monitoring were done in the San Bruno Mountais. A RECOVERY PLAN was drawn up now out of date. Contact us if you need a copy. Recovery Plan for San Bruno Elfin and Mission Blue Butterflies. October 10, 1984Its protection falls under the jurisdiction of the federal Endangered Species Act. While the state of California has enacted an Endangered Species Act, it is quite specific about what affords its protection. Sec. 2062 of the California Endangered Species Act, under definitions, declares, "Endangered species" means a native species or subspecies of a bird, mammal, fish, amphibian, reptile, or plant which is in serious danger of becoming extinct." There is no provision for a state endangered listing in California for any insect. The mission blue butterfly is not protected by state statute in California. I did a lot more research on the endangered species, restorations, laws, etc (plus below topics). However, I ran out of time to sort through it all and write the paper and it is 1AM before our hike Saturday. Some other areas were:
Georgette References and Internet Links Ecology of GGNRA Bio 28 Mission Blue Butterfly 1 SFSU Department of Geography, Geography 316: Biogeography
The Endangered Mission Blue Butterfly Of CA, Indicator Of An Imperiled Natural Ecosystem http://www.mountainwatch.org/mountain/fauna/missionbluebutterfly.htm 10b,21 San Bruno Mountain Watch Site, For involvement with restorations http://www.mountainwatch.org/organize/index.htm 11 BayNature Exploring Nature iin the SF Bay Area, Bay Area Butterfly Resources http://baynature.org/articles/web-only-articles/bay-area-butterfly-resources/?searchterm=mission%20blue%20butterfly 12 US Fish & Wildlife Service, Mission blue butterfly (Icaricia icarioides missionensis) http://ecos.fws.gov/speciesProfile/SpeciesReport.do?spcode=I00J 15 GGNRA Mission Blue Butterfly, 2008 Endangered species big year http://www.ggnrabigyear.org/missionbluebutterfly.html 1a Wikipedia, Mission blue butterfly habitat conservation http://en.wikipedia.org/wiki/Mission_blue_butterfly_habitat_conservation 16b Wikipedia, Mission blue butterfly http://en.wikipedia.org/wiki/Mission_blue_butterfly 17b Wikipedia, Lycaenidae http://en.wikipedia.org/wiki/Lycaenidae 18 Answers.com, Mission Blue Butterfly Habitat Conservaton http://www.answers.com/topic/mission-blue-butterfly-habitat-conservation 20 Arnold, San Bruno Mountain Watch Education Leaflet Series No. 7 http://www.mountainwatch.org/organize/index.htm 33 Google Images, Mission Blue Butterfly http://images.google.com/images?hl=en&rlz=1T4ADBR_enUS226US228&q=mission+blue+butterfly&um=1&ie=UTF-8&sa=X&oi=image_result_group&resnum=1&ct=title 40 GGNRA, park areas http://en.wikipedia.org/wiki/Golden_Gate_National_Recreation_Area - - |