Over more than four decades of running his annual Beer for a Butterfly Contest, Professor Art Shapiro hasn’t had to buy many pitchers for anyone but himself.

The beer (or its equivalent) is for whomever catches the first cabbage white butterfly of the year in Yolo, Solano or Sacramento counties.

Shapiro started the contest in 1972 and has won all but three times. Graduate students comprise his main competitors, but they don’t lose out entirely, as Shapiro is happy to share his prize pitcher.

While “beer” shares the spotlight, the contest is more about the “butterfly” and science, in that Shapiro records the date the Pieris rapae first takes flight as part of his research on biological response to climate change.

“It is typically one of the first butterflies to emerge in late winter,” Shapiro said. “The cabbage white is now emerging a week or so earlier on average than it did 30 years ago here.”

The insect requires a string of days above a certain temperature before first flight, and that date has been gradually coming earlier as the region warms. In 2015 he caught his first specimen (and won his contest) on Jan. 26 — one of the latest dates in recent history.

Shapiro said he’s already seen the cabbage white flying, so it’s anybody’s game. To participate, look for an adult cabbage white butterfly (it’s white with faint black spots on the top half, and can often be found in vacant lots, fields and gardens) and bring it — alive — to the Department of Evolution and Ecology, 2320 Storer Hall, during normal business hours to be verified.

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