The next time you see a small white butterfly fluttering through town, it could land you a free pitcher of beer or the cash equivalent.
Arthur Shapiro, professor of evolution and ecology at UC Davis continues his annual “Butterfly-for-Beer” contest, now in its 38th year, this month.
Shapiro will reward whoever captures the first live cabbage white butterfly (Pieris rapae) of the year. Only adult butterflies found outdoors in Sacramento, Solano or Yolo counties are eligible.
Shapiro has conducted detailed monitoring of butterfly flight seasons since 1972.
“This provides a unique database for analyzing the biological response to climate change,” he said.
Shapiro said he chose this species because it is one of the most common in California.
“It’s everywhere, it’s easy to find,” he said. “If you are going to have a contest, it’s an obvious choice. You don’t have to go backpacking into the wilderness to find it– it’s in vacant lots.“
The wanted butterfly is white in color and approximately one and one-quarter inches long. It may have black spots near its outer wings.
“Every winter usually signals the ‘end‘ of the butterfly season, as butterflies usually only fly on warm sunny days,” said Greg Kareofelas, an observer of local fauna and friend of Shapiro in an e-mail.
“Art chose the cabbage white to be a ‘sign‘ of the start of the next season for a number of reasons,” he said. “It spends the winter as a chrysalis that will only emerge when the warm days of the next year are detected. Hence, the sign of the next season. Long term monitoring of this emergence date can detect changes in the weather patterns.“
Shapiro said he conducts the contest to make sure he is keeping up with what is happening in nature. “If people beat me frequently it means I’m not working hard enough to keep track of my bug,” he said.
“It just occurred to me that it would be fun to have people competing with me; it would keep me on my toes, it would keep me working hard,” he said.
Most of Shapiro’s competition comes from the graduate students in his lab who “are avid to beat the boss,” he said. “Occasionally they do, but not very often.“
In addition, Shaprio said the contest also raises public awareness of climate change and its consequences.
“Butterflies are coming out earlier than they used to in late winter,” he said. “[They appear] averaging about a week earlier than they did thirty-some years earlier.“
The emergence of the first butterfly is variable – first sightings over the years have ranged from Jan. 1 to Feb. 22. Last year, the first butterfly was caught on Jan. 19.
“One of the funniest things about the contest is that almost every year someone will contact me in June and say ‘I’ve got one, did I win?'” Shapiro said.
“The thing that makes butterflies important [indicators] is that there is so much known about them,” Kareofelas said. “Butterflies can be seen easily – other little insects can’t.“
So if you can monitor a part of that fauna that’s easily seen and easily noticed, you draw an assumption that if there’s a problem in the butterfly population, there’s likely a problem in other insect populations as well, he said.
“So maybe there’s a problem in the environment,” Kareofelas said. “If [the butterfly is] in trouble, then everything else is in trouble.“
Shapiro’s contest is open to everyone in the community. Butterflies found should be brought alive to the receptionist in the evolution and ecology office at 2320 Storer. Entrants should include information about the time, date and place found. Butterflies captured when the department office is closed can be stored live for a few days in the refrigerator.
Shapiro said those interested in more information are welcome to contact him at email@example.com.
ANNA OPALKA can be reached at firstname.lastname@example.org.