Tuesday, May 09, 2006

Butterflies continue to face challenges

This article is not saying anything about global warming, but my intel says that California's weather is directly related to global warming.

States a press release from UC Davis, "Cold, wet conditions early in the year mean that 2006 is shaping up as the worst year for California's butterflies in almost four decades, according to Art Shapiro, professor of evolution and ecology at UC Davis.

That's a turnaround from last spring, when millions of painted lady butterflies migrated through the Central Valley. But other species have seen steep declines in recent years and could disappear from the region altogether.

'It has been the worst spring for butterflies of my 35 in California,' Shapiro said. 'There will probably be long-term repercussions, especially for species already in serious decline.'

Shapiro said that at most of his study sites, he is seeing half or less than half the number of species present at this time in an average year, and far fewer individual butterflies than usual. For example, at Gates Canyon near Vacaville he counted 10 species and 43 individuals on April 18, 2006. At the same site on April 19, 2005, he counted 21 species and 378 butterflies.

This winter's weather conditions may have a lot to do with the drop in numbers. The early winter was mild, with not enough cold to end the winter dormancy or 'diapause' of most butterflies, so they did not emerge to take advantage of early warm weather in February. Then March turned cold and wet, wiping out the breeding of species that had emerged."