Parnassius behrii (Sierra Nevada Parnassian)
Credit: Zachary MacDonald
about the species
The Sierra Nevada Parnassian (Parnassius behrii) is a large, white butterfly, endemic to the central and southern regions of the Sierra Nevada mountain range. These butterflies are easy to love for their exuberant animation across alpine meadows and scree slopes. Unfortunately, P. behrii and their high-elevation habitats are particularly sensitive to changing climatic conditions. As temperature warm and treelines continue to advance up mountain slopes, some P. behrii populations may be able track their climatic niche by similarly moving upslope. However, many populations already occur near mountain tops, limiting their potential for elevation shifts. Diversification models show that Parnassius have been quite sensitive to changes in climatic conditions over the past 10,000 years, with extinction rates increasing with higher temperatures. Due to its restricted range and high habitat specificity, P. behrii is the most vulnerable North American Parnassius species. It’s only known larval host plants are Stonecrops (Sedum spp.), which are generally restricted to alpine meadows and rocky outcrops. Available data suggest that many P. behrii populations have been declining or have gone extinct in recent decades.
why species was selected
Parnassius behrii is likely to become a species of conservation concern as habitat and climatic conditions continue to change in alpine environments. Coupling whole-genome sequence data with forward-in-time landscape and environmental modelling will allow us to predict how these changes are likely to affect the persistence of individual populations and the entire species. This information can be used to inform future translocation and reintroduction efforts, should they be required. Two other butterflies, Colias behrii and Oeneis chryxus ivallda, are also endemic to the Sierra Nevada, and are similarly being addressed by the CCGP. Comparative analyses across these species will help conservation biologists understand how high-elevation ecosystems are changing.
