endemic to a single state or province
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: (<100 square km (less than about 40 square miles)) Endemic to Antioch Dunes NWR and iimmediately adjacent (<150 meters) land. The entire dune system is now about 67 acres, not all of which supports Lange's metalmark. About 55 acres are protected probably including all occupied habitat. The original range was proebably a few dozen square miles.
Comments: Riverbank sand dunes; host is Eriogonum latifolium ssp. auriculatum. Only uses plants that are four or five years old.
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 1 - 5
Comments: There are two remnant colonies, parts of an originally much larger population, that had some gene flow as recently as the 1980s, and quite possibly since then, and are less than a mile apart. One occurrence.
50 - 250 individuals
Comments: Based on actual population estimates by mark release-recapture, there were probably fewer than 1000 adults most years from 1977 to 1983. Since 1986 there are only estimates based of numbers observed. Even if all individuals present were observed, which is very unlikely, this methodology would underestimate actual population size because daily turnover, and early and late flying individuals are not accounted for. Nevertheless these peak are quite sufficient for monitoring relative change, and such estimates reached 2000 in 1991 and a maximum of 2345 in 1999, followed by a steady decline down to 45 in 2006, and 89 in 2007. It is possible, but undocumented and should not be assumed, that some pupae remain in diapause through unfavorable years and that very low numbers some years in part reflect this.
National NatureServe Conservation Status
Rounded National Status Rank: N1 - Critically Imperiled
NatureServe Conservation Status
Rounded Global Status Rank: T1 - Critically Imperiled
Reasons: This is a critically imperiled subspecies in decline and on the verge of extinction as of 2006-2007.
Other Considerations: Note that the above information dates from 1981.
Date Listed: 06/08/1976
Lead Region: California/Nevada Region (Region 8)
Where Listed: Entire
Population location: Entire
Listing status: E
For most current information and documents related to the conservation status and management of Apodemia mormo langei , see its USFWS Species Profile
Global Short Term Trend: Decline of 70 to >90%
Comments: See USFWS (1998) the trend has been steadily downward after 1999, with a decline of more than 95%.
Global Long Term Trend: Decline of >90%
Comments: Undoubtedly well over 99% compared to pre-sand mining numbers.
Degree of Threat: Very high - high
Comments: The main threat as of 2008 is thought to be invasive weeds affecting the foodplant, and possibly other aspects of the habitat. Numbers since 2005, and probably since 2002 are low enough for genetic deterioration to be likely, and probably inevitable. Fire also a threat, and while not mentioned by USFWS (2008), the Xerces Society red list profile of this species (Black and Vaughan 2005) points out that about 40% of the habitat burned in 2000 and that recent counts have been under 450 adults. However, the actual USFWS data show about 1200 adults in 2000 (pre-fire) and 700 in 2001, which is closely proportional to the extent of the burn, declining to slightly over 500 or less after that, which is unlikely to be attributable to the fire. Foodplants probably need a few years to recover to useable condition, and most individuals of any life stage would perish in the area actually burned. The habitat is largely protected from direct human disturbance.
Biological Research Needs: Possibly habitat issues.
Global Protection: None. No occurrences appropriately protected and managed
Comments: Most of the occurrence is on USFWS land and is protected and management is being attempted. The rest is on Pacific Gas and Electric property and USFWS has access to this portion as well.
Needs: Captive breeding became essential and is underway in the mid 2000s. Unless habitat issues, apparently mostly invasive weeds, can be adequately addressed very soon this butterfly is likely to become extinct in the wild. Even with weed control recovery of the foodplants would take a season or more.
Apodemia mormo langei
Apodemia mormo langei, known by the common name Lange's Metalmark Butterfly, is an endangered North American butterfly. It is a subspecies of the Mormon metalmark and belongs to the family Riodinidae. The butterfly is endemic to California, where it is known from one strip of riverbank in the San Francisco Bay Area. A 2008 count estimated the total remaining population at 131 individuals. Since 2011, this number has dropped to about 25–30.
Lange's metalmark is a fragile, brightly colored butterfly in the Riodinidae (metalmark) family. Adult wingspan varies from 1-inch (25 mm) to 1.5-inch (38 mm). Dorsal wings are largely black with white spots. Red-orange coloration extends through the inner forward half of the forewing, the hindwing bases, and a small central patch subtended by black. Below, the wings have a more muted pattern of gray, white, black, and orange.
Status and distribution
The butterfly has been classified in the USA as a Federal Endangered Species (Federal Register 41:22044; June 1, 1976).
Lange’s metalmark butterfly was historically restricted to sand dunes along the southern bank of the Sacramento River, and is currently found only at Antioch Sand Dunes (a misnomer, as the sand was long ago removed and the landscape is now hilly scrub) in Contra Costa County, California. Most of the habitat is now part of the Antioch Dunes National Wildlife Refuge, administered by the Don Edwards San Francisco Bay National Wildlife Refuge Complex. Recent population counts have ranged from several hundred to more than a thousand individuals. While the Antioch Dunes Recovery Plan of 25 April 1984 has been put under action, no critical habitat has been designated as yet.
In the early 1900s, the isolated dune habitat in the Sacramento-San Joaquin River Delta began to experience a dramatic change as human development expanded. The easily accessible sand was harvested to make bricks. Large-scale sand mining and industrial development fragmented the sand dune habitat until only a small portion of the original ecosystem remained. Nonnative grasses and other vegetation encroached on the sand dunes to crowd the few remaining endangered plants. By the time the Antioch Dunes Refuge was established, only a few acres of remnant dune habitat supported the last natural populations of Antioch Dunes Evening Primrose (Oenothera deltoides ssp. howellii), Contra Costa wallflower (Erysimum capitatum var. angustatum) and Lange's metalmark.
A reservoir of moving sand is essential to maintain the dynamic ecology of the dunes, as moving sand opens areas for the establishment of seedling plants. Roto-tilling has contributed to the invasion of exotic vegetation that stabilizes the remaining sand-dune habitat and competes with native dune vegetation. Habitat improvement activities have included dune restoration, hand-clearing of non-native plant species, planting buckwheat seedlings and restriction of public access to avoid trampling and fire.
A nonprofit environmental group has been breeding the butterflies and plans to release caterpillars into the dunes in 2010.
All the life stages of Lange's metalmark butterflies are found close to the larval food plant, buckwheat (Eriogonum nudum ssp. auriculatum). The eggs are deposited on buckwheat leaves near the leaf petiole during a short mating flight of 10 days' duration. Larvae hatch during the rainy months. Larvae are known to feed only on buckwheat. The adults may use buckwheat, butterweed (Senecio douglasii) for nectar. Lange's metalmark butterfly also use silver lupine (Lupinus albifrons), for mating.
Unlike the many butterfly species that have several generations a year, Lange's metalmark has only one. The fecundity of wild individuals is low. Detailed life history and physiological requirements of this species are unknown.
|Wikimedia Commons has media related to Lange's metalmark butterfly (Apodemia mormo).|
- Arnold, R. A. 1980. Ecological studies of 6 endangered butterflies: island biogeography, patch dynamics, and the design of nature preserves. PhD thesis. Univ. of Calif., Berkeley. Berkeley, CA.
- Howe, W. H. (ed.). 1975. The butterflies of North America. Doubleday and Co. Garden City, NY.
- Opler, P. A. and J. A. Powell. 1962. Taxonomic and distributional studies on the western components of the Apodemia mormo complex (Riodinidae). Journal of the Lepidoptera Society 15:145–171.
- Thelander, C. ed. 1994. Life on the edge: a guide to California's endangered natural resources. BioSystem Books. Santa Cruz, CA. p 432-433.
- U.C. Berkeley, Essig Museum of Entomology. California's Endangered Insects.
- U.S. Fish & Wildlife Service. 1984. Antioch Dunes Recovery Plan. Portland, Oregon.
EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.
To request an improvement, please leave a comment on the page. Thank you!