On Jan. 1, Professor Art Shapiro and others will set out once again to capture cabbage white butterflies — in a scientific endeavor that will also net someone a pitcher of beer.

Shapiro, who launched the contest in 1972, offers the beer (or cash equivalent) to whomever nets the first cabbage white of the new year. As a professor of evolution and ecology, he uses the information in his research into biological responses to climate change.

The cabbage white, scientific name Pieris rapae, is typically one of the first butterflies to emerge in late winter, Shapiro said. Data from his beer-for-a-butterfly contest, covering Yolo, Solano and Sacramento counties, show emergence dates ranging from Jan. 1 to Feb. 22, averaging about Jan. 20 — a week or so earlier than the butterfly’s average emergence date 30 years ago.

Shapiro, who averages more than 200 days a year in the field, usually wins his own contest, losing only three times in 42 years!

He won the 2013 contest with a cabbage white catch on Jan. 21. And then he did what he always does when he wins: He shares the beer prize with his graduate students, who are usually his toughest competitors.

The rules require an adult specimen, caught outdoors (look for the cabbage white amid its host plants, weedy mustards, in vacant lots, fields and gardens). Take your catch — live — to the Department of Evolution and Ecology, 2320 Storer Hall. If the office is not open, keep your butterfly in a refrigerator — “A few days in the fridge will not harm it,” according to a contest flier — until you can deliver the cabbage white.

You must provide the exact time, date and location of the capture, plus your name, address and contact information (email preferred).

For more information, contact  Shapiro by phone, (530) 752-2176, or email.

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