Skip to main content

Oregon Silverspot Butterfly

Oregon silverspot butterfly


The Oregon silverspot butterfly (Speyeria zerene hippolyta ) is a medium-sized butterfly, predominantly orange and brown with black veins and spots on its hindwings and bright silver spots on its forewings. The length of its forewings is about 1.1 in (2.9 cm). The female is usually slightly larger than the male. This butterfly is listed as threatened by the U. S. Fish and Wildlife Service and has been protected under the Endangered Species Act since 1980.

Inhabiting a very restricted range, the Oregon silverspot occurs only in salt spray meadows along the Pacific coast in Oregon and Washington. This habitat is characterized by heavy rainfall, fog, and mild temperatures. The most critical feature of this habitat, however, is the presence of the western blue violet (Viola adunca ), the host plant of the butterfly's larva. For two months each spring, larval Oregon silverspots feed on violet leaves before entering the pupa stage of development. This butterfly was historically present at 17 locations along the coasts of Oregon and Washington, but now only five populations in Oregon are known to exist with certainty.

Housing developments and recreational uses of the coast that destroy or degrade butterfly habitat are the major threats to this subspecies's survival. Natural fire patterns in its meadow habitat have been suppressed, allowing nonnative vegetation to mix with native plants and changing the habitat's character. An area of Lane County, Oregon with a healthy population of Oregon silverspots has been designated critical habitat for this subspecies. Expansion of the population of western blue violets in this area will be encouraged by the control of saplings and other invading plants. Transplantation of western blue violets to other sites with suitable meadow habitat may also be attempted. A recovery plan was put into effect in 1999 and monitored through 2000. It was headed by Lewis and Clark College, the Oregon Zoo in Portland, and the Woodland Park Zoo in Seattle and consisted of rearing the larvae in captivity, then returning the butterflies to the wild. Although the Oregon silverspot butterfly is not in immediate danger of extinction , its specific habitat requirements and the vulnerability of that habitat to degradation and destruction, makes intervention necessary to ensure the long-term survival of this subspecies.

[Christine B. Jeryan ]


RESOURCES

BOOKS

Howe, W. H. The Butterflies of North America. Garden City, NY: Doubleday, 1975.

OTHER

U.S. Fish and Wildlife Service Revised Recovery Plan Published for the Oregon Silverspot Butterfly. November 29, 2001 [cited May 2002]. http://news.fws.gov/NewsReleases/R1/C71501ED-5742-4E26-965408A77BC0875F.html>.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Oregon Silverspot Butterfly." Environmental Encyclopedia. . Encyclopedia.com. 16 Aug. 2018 <http://www.encyclopedia.com>.

"Oregon Silverspot Butterfly." Environmental Encyclopedia. . Encyclopedia.com. (August 16, 2018). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/oregon-silverspot-butterfly

"Oregon Silverspot Butterfly." Environmental Encyclopedia. . Retrieved August 16, 2018 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/oregon-silverspot-butterfly

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.