Endangered Butterflies

The lists breaks down into nine brush-footed species, eight blue species, one metalmark species and one swallowtail species.

Brush-footed Butterflies (Nymphalidae)

• Bay Checkerspot (Euphydryas editha bayensis): Threatened
• Behren's Silverspot (Speyeria zerene behrensii): Endangered
• Callippe Silverspot (Speyeria callippe callippe): Endangered
• Mitchell's Satyr (Neonympha mitchellii mitchellii): Endangered
• Myrtle's Silverspot (Speyeria zerene myrtleae): Endangered
• Oregon Silverspot (Speyeria zerene hippolyta): Threatened
• Quino Checkerspot (Euphydryas editha quino_: Endangered
• Saint Francis' Satyr (Neonympha mitchellii francisci): Endangered
• Uncompahgre fritillary (Boloria acrocnema): Endangered

Blues, Coppers and Hairstreaks (Lycaenidae)

• El Segundo blue (Euphilotes battoides allyni): Endangered
• Fender's blue (Icaricia icarioides fenderi): Endangered
• Karner's Blue (Lycaeides melissa samuelis): Endangered
• Lotis Blue (Lycaeides argyrognomon lotis): Endangered
• Mission Blue (Icaricia icarioides missionensis): Endangered
• Palos Verdes blue (Glaucopsyche lygdamus palosverdesensis): Endangered
• San Bruno Elfin (Callophrys mossii bayensis): Endangered
• Smith's Blue (Euphilotes enoptes smithi): Endangered

Metalmark Butterflies (Riodinidae)

• Lange's Metalmark (Apodemia mormo langei): Endangered

Swallowtails (Papilionidae)

• Schaus Swallowtail (Heraclides aristodemus ponceanus): Endangered

Having brush-footed butterflies lead the list is easily understandable. With over two hundred species, it's the largest of the butterfly families.

With about one-half the number of species (100), the Lycaenidae species almost equaling the listing with the brush-footed presents a sort of a puzzle. Why are there a disproportionate number of endangered blue butterflies?

The best answer to date combines explanations of limited range and limited diets. As a rule of thumb, the larvae of many blue butterfly species only consume one, or maybe two different plants that are limited to a small, specific, geographic location.

The video, for example, provides a short and simple look at the Fender's Blue butterfly, a subspecies of the Boisduval's Blue (Plebejus icarioides), that was listed as endangered in 2000. Despite the existence of many lupine species in its former range, the Fender's Blue larvae only consume Kincaid's lupine and spur lupine.

When development encroaches on the plants, the butterfly populations suffer.

Along with habitat protection, a variety of captive breeking programs that involved both breeding the butterfies and growing the larval host plants have been enacted as measures to revive these endangered populations.

© 2010. Patricia A. Michaels