Have you heard the story about a lepidopterist and a herpetologist who walk into a bar? And, a cabbage white butterfly, Pieris rapae, goes, too?
That's exactly what happened on Wednesday, Feb. 4, when the co-winners of the 2026 Beer-for-a-Butterfly Contest celebrated with beer and conversation at a Davis bar.
UC Davis Distinguished Professor Emeritus Art Shapiro, who has sponsored and judged the contest since 1972 (and usually wins), declared himself and Kathryn “Kat” Calderala of Davis--a consulting biologist specializing in reptiles and amphibians--as the co-winners.
Shapiro sighted—but did not collect--a cabbage white butterfly, a male, at 12:02 p.m. in West Sacramento, Yolo County, and a few minutes later, at 12:08, Calderala collected a male rapae in a ditch in front of an auto recycling business in Woodland, off County Road 25.
The herpetologist brought the butterfly to the bar, Burgers and Brew, as proof, and later released it where she collected it.
'Toads and Turtles Are My Jam'
Calderala, who moved to Davis last summer from Monterey but is originally from Fresno, initially emailed the lepidopterist: “I hate to break it to you but I'm a herpetologist. Toads and turtles are my jam. I was just out looking at one of the local burrowing owls when I saw the outbreak of whites and thought What the heck?”
She owns "a tiny consulting company, Livewire Ecological Consulting, Inc., which covers all of Central California for field support services (special-status species surveys, etc.)."
“I’m still fairly new to town so have been trying to get up to date on the local special-status species in the county,” Calderala commented. “On this day I was traveling around looking for wintering burrowing owls and happened to see an outbreak of whites in a ditch. I immediately thought about an article someone posted on Linked In, saying the first white had not been found as of the 28th. So I flipped around and went back to chase down a white. Dumb luck, truly.”
The rules of the "Suds for a Bug" contest specify that the first person to collect a live cabbage white butterfly of the year in the wild and within the three-county area of Yolo, Sacramento and Yolo--and is judged the winner--wins a beer or an alternative drink. The point of the contest, Shapiro says, is “to get the earliest possible flight date for statistical purposes." It's all part of his scientific research involving long-term studies of butterfly life cycles and climate change. In its larval stage, the butterfly is a pest of cole crops, including cabbage, broccoli and kale.
In addition to the winning male that Shapiro spotted at the West Sacramento site, he soon counted multiple others there: "a female at 12:06, another male at 12:30, another female at 12:53, and a two-male chase at 12:55. So there ain't no doubt rapae is out!”
'The Suspense Is Killing Me'
“Y'all have no idea what a relief it is to have rapae out,” Shapiro told his email posse on Feb. 2. He earlier lamented that "the suspense is killing me."
Feb. 2 is one of the modal first flight dates, having occurred also in 1982, 1995, and 2005.
Shapiro, who has monitored butterfly population trends in central and northern California since 1972 and maintains a research website at http://butterfly.ucdavis.edu/, said the 2026 winner may have been in Benicia. A sighting was reported, “but it wasn't fully documented, and Benicia is in Solano County but is climatically rather different. I would have expected it in Suisun, but it wasn't. This is meteorologically a very odd year. But Feb. 2 was fated to be the day!”
Shapiro added that Feb. 2, too, was the first “good moth night of the year," according to John "Moth Man" DeBenedictis of Davis. “These things cumulate physiologically and eventually have to reach a critical threshold. So I couldn't predict who would get the bug on the 2nd, but I was not surprised that I was not the only one.“
Matt Forister Creates the Graphs
UC Davis doctoral alumus Matt Forister, the McMinn Professor of Biology at the University of Nevada, and Shapiro's former graduate student, annually creates a graph chronicling the first flight. This year, Forister messaged: “Per tradition, here's the graph, with the current year in red; the slope is just a tad more shallow (was -0.34, now -0.31); not per tradition, the graph this year includes a wiggly spline fit (orange line) to allow for the possibility that the once simple progression of earlier emergence might be giving way to something more complex; maybe this year reflecting the tule fog of an, or perhaps reflecting the lower densities of bugs (rapae is declining, like most things, despite being a weedy animal) which we can expect to result in later detection even in a warming-earlier-emergence world.”
Shapiro has been defeated only four times in the contest, and all by UC Davis graduate students. Three were his grad students: Adam Porter defeated him in 1983; and Sherri Graves and Rick VanBuskirk each won in the late 1990s. The most recent non-Shapiro graduate student to win was Jacob Montgomery, who collected the winner outside his home in west Davis in 2016.
