Beer For a Butterfly

By Kathy Keatley Garvey

He did it again.

Professor Arthur Shapiro of the UC Davis Department of Evolution and Ecology snagged the first cabbage white butterfly of 2012 on Sunday, Jan. 8 in West Sacramento, Yolo County, to win his own beer-for-a-butterfly contest.

Shapiro netted the butterfly (Pieris rapae), a newly emerged male, at 11:50 a.m. under a hazy skies with a temperature reading of 60 degrees.

Shapiro, a noted butterfly expert and distinguished professor, has sponsored the Pitcher-of-Beer-for-a-Butterfly Contest since 1972 and recalls having lost only three times, each time to one of his graduate students. In keeping with tradition, he offers a pitcher of beer (or a cash equivalent) for the first cabbage white collected in the three-county area of Yolo, Solano and Sacramento.

Shapiro immediately announced he would take his graduate students and their significant others out for a beer in a few days to celebrate. His students are typically his fiercest competitors in the contest, which is designed to aid in his studies of biological response to climate change.

Sunday’s capture date is the second earliest of record in 40 years, the earliest being Jan. 4, 1990. Shapiro said it reflects “the extraordinary sunny and dry weather that has persisted all winter, with warm afternoons, frosty nights, and little cloudiness or fog.”

“There have been numerous high-temperature records set in northern California, both in the valleys and in the Sierra Nevada," Shapiro said. “The abnormal conditions cannot be linked causally to global warming but are related somehow to the current La Nina, now in its second year.”

Shapiro noted that many regional first-flight records for butterflies were set during the severe drought of 1975-76, before “ the signature of global warming was observed.”

“In 1976 we had species flying at the end of January that normally come out in March,” Shapiro observed. “If the current weather pattern continues another two weeks, all those records will be at risk.”

He also pointed out that due to the lack of rainfall, germination of herbaceous plants has been very poor. “If butterflies and other insects are tricked by the weather into emerging early, the resources they need will simply not be there!”

Shapiro sponsors the annual contest to draw attention to Pieris rapae and its first flight. "I am doing long-term studies of butterfly life cycles and climate. Such studies are especially important to help us understand biological responses to climate change. The cabbage white is now emerging a week or so earlier on average than it did 30 years ago here."

Shapiro, who is in the field more than 200 days a year, has been defeated only three times since 1972.  Adam Porter found the first cabbage white in 1983; and Sherri Graves and Rick VanBuskirk each won the contest in the late 1990s.

Shapiro maintains a website on butterflies at http://butterfly.ucdavis.edu/, where he records  butterfly population trends that he monitors in Central California. He has surveyed fixed routes at 10 sites since as early as 1972. They range from the Sacramento River delta, through the Sacramento Valley and Sierra Nevada mountains, to the high desert of the western Great Basin. The sites, he said, represent the great biological, geological, and climatological diversity of central California.

Shapiro and biologist/writer/photographer Tim Manolis are the co-authors of "A Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions," published in 2007 by the University of California Press.

Shapiro is a Fellow of the American Association for the Advancement of Science, the Royal Entomological Society, and the California Academy of Sciences.