Updated 8 p.m. Feb. 3: Professor Art Shapiro officially closed his Beer for a Butterfly contest tonight without a winner for the first time in the contest’s 49-year history. For the “complicated” reasons explained below, he had extended the contest until 5 p.m. Sunday (Feb. 2), then again to 5 p.m. today — but no one brought in a cabbage white butterfly (Pieris rapae). As for the beer that went unclaimed, Shapiro said he intends to go drink a pitcher with a friend later this week. On a scientific note, about the late date of the cabbage white’s first flight, Jan. 30, the latest since 2011 and the second latest since 2005, Shapiro had a warning: “This does not mean global warming is a hoax!”

Professor Art Shapiro predicted it: The cabbage white butterfly would be out this week, he said in a Jan. 25 email to his “posse,” alerting them to their opportunity to win his annual Beer for a Butterfly contest — the prize pitcher going to the person who catches the first cabbage white of the new year.

And there it was today (Jan. 30), in the Putah Creek Nature Park in Winters, spotted by none other than Shapiro himself (as usual, given that he has won almost every year since he started the contest 49 years ago).

“At 11:16 a.m. I spotted a Pieris rapae dorsal basking on a malva leaf on the steep S-facing slope above the creek,” the professor of evolution and ecology said in a blow-by-blow recap of his morning in the field. “It was a female. I could only approach it from below, and before I could close in, it detected me — and took off.

“It flew directly across the creek, where I could not follow. Apparently the shaded N-facing slope was not to its liking. At 11:20 it flew directly back across the creek, about 15 feet off the ground — and kept going. It went over the riparian trees and over the top of the slope, on a bearing that would take it into the middle of Winters (the town).

“Hoping it would return, I milled around fruitlessly for 90 minutes. The temperature rose to a balmy 66 degrees Fahrenheit. I never saw it again — or anything else; no nymphalids.”

Today’s date is in the books ...

Still, he got what he needed: the date of the cabbage white’s first flight of 2020, to add to his database going back to 1972, for research measuring biological response to climate change.

As the climate has warmed, the cabbage white’s first-flight date has gradually moved up — to a range of Jan. 1 to Feb. 22. Interestingly, Shapiro said, this year’s first flight of Jan. 30 was the latest for the valley rapae since the first flight of Jan. 31, 2011, “and one has to go back to Feb. 2, 2005, for the next one later than this. That is, this is really late!”

But what about the contest? Is he the winner — again? Not exactly. Or, as he headlined his recap: “Rapae Is Out. But It’s Complicated.”

“I knew this would happen someday — it almost has in the past! — and I had a protocol in place.”

“This” is the situation: The cabbage white made its first flight, but no one has the required voucher — or proof, in the form of a live specimen — to claim the prize.

A fair protocol

The voucher requirement, he said, is “the only way I can confirm the accuracy of other people’s records.”

And even though he has “perfect faith” in his own sight — that is, he knows he saw a rapae today — “I cannot declare myself the winner,” because he doesn’t have a voucher.

In fairness to potential competitors, though, his offer stands: A pitcher of beer to the first person to bring in a live rapae from the contest area (Sacramento, Yolo and Solano counties) — but you have only until 5 p.m. this Sunday (Feb. 2) to get it done. More about the contest, including the rules.

And, get this: Shapiro said he will not try to beat anyone to a voucher! So everyone else gets a chance! If no one turns one in, he will declare the contest closed with no winner this year. “I think that’s fair,” he said.

“I can visualize a stream of thirsty people with nets converging on Winters as soon as this gets out!”

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