Satyrium
acadica
Acadian Hairstreak
Range:
This species is found in Canada from southeastern British Columbia east to Nova
Scotia, and in the U.S. from Idaho to the east coast, extending south as far
as Colorado, east to northern Virginia. In Idaho,
it occurs in the northern and south central parts of the state.
Habitat:
This species can be found in moist habitats such as along
streams and in wet fields and meadows.
Diet:
Caterpillar:
Caterpillars feed on the leaves of willows (Salix spp.).
Adult:
Butterflies drink flower nectar, commonly from milkweeds (Asclepias
spp.) and dogbane (Apocynum spp.).
Ecology:
Eggs are laid in the fall, overwinter, and hatch in the spring.
There is only one generation of caterpillars each year. The caterpillar is equipped
with a honey gland, also known as a dorsal nectary organ, which
emits a sugary solution agreeable to ants. The ants feed on the solution and
in turn protect the caterpillar from predators. Adults generally fly from June through August. The tails
of the hindwings of the butterfly resemble antennae and can act to fool predators
into biting the wrong end of the butterfly, allowing it to escape. This species
closely resembles the California Hairstreak and it can be difficult to distinguish
between the two where their ranges overlap. However, the California Hairstreak
occurs near oaks (Quercus spp.) while the Acadian Hairstreak occurs near
willows (Salix spp.).
Reproduction:
Males perch in
the afternoon on short vegetation near willows to wait for receptive females,
and may occasionally actively patrol
for them. Females lay white eggs, tinted with green or pink, on the twigs of
willows.
Conservation:
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Global Rank: | G5; populations are widespread, abundant, and secure. |
Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm (Version 05Nov98).
Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies. Second Edition. Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.
Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.
Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.
Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.