- Author: Kathy Keatley Garvey
The winner of the 2018 Beer-for-a-Butterfly Contest, sponsored by Art Shapiro, UC Davis distinguished professor of evolution and ecology, is…drumroll…Art Shapiro.
Shapiro collected the cabbage white butterfly, Pieris rapae, at 11:23 a.m. Friday, Jan. 19 in one of his frequented sites—a mustard patch by railroad tracks in West Sacramento, Yolo County. He caught it with his hands--no net.
“Today should not have been the day,” he said, noting the weather forecast of "a chance of rain" when he left his Davis home at 10 a.m. for West Sacramento.
“I spotted the male butterfly dorsal basking (sunbathing) on low vegetation shortly after the first cumulous formed at 11 a.m.,” Shapiro said. “As I approached to collect it, a small cumulus occluded the sun and it closed its wings over its back--allowing me to just pick it up without using my net at all, and drop it into a glassine envelope. It turned out that that was the ONLY cloud that crossed the sun in the next two and a half hours! It got up to about 60 degrees and was a gorgeous day with a trace of a west wind.”
Shapiro said that "It probably emerged an hour or so before I got there so this really is the start of the season! Let the rites of spring begin!”
He described the butterfly as quite yellow instead of white. “Cold weather promotes sepiapterin formation, so early ones are often quite yellow.”
Apparently the newly emerged butterfly had not yet flown. When he placed it in the glassine envelope, “it voided meconium, metabolic wastes of metamorphosis, normally ejected before the first flight.”
Shapiro, who maintains a research website at http://butterfly.ucdavis.edu, launched the contest in 1972 as part of his scientific research to record the first flight of the butterfly in the three-county area of Sacramento, Yolo and Solano. He offers a pitcher of the beer, or its equivalent, to the first person who collects the “first of the year” butterfly. It's a contest he usually wins. He has been defeated only four times, and all by UC Davis graduate students.
His former graduate student, Matt Forester, now a professor of biology at the University of Nevada, Reno, and a research collaborator with Shapiro, accurately predicted the first butterfly would be found on Jan. 19.
“Since 1972, the first flight has varied from Jan. 1 to Feb. 22, averaging about Jan. 20,” Shapiro noted.
This is the seventh year the winning butterfly has been collected in Yolo County. Last year Shapiro found the winner on the UC Davis campus; in 2016, graduate student Jacob Montgomery netted the winner outside his home in west Davis, and Shapiro collected all five winners from 2012 to 2015 in West Sacramento.

- Author: Kathy Keatley Garvey
And the winner is: Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, who has sponsored the annual contest since 1972 as part of his long-term studies of butterfly life cycles and climate.
The contest rules indicate that the first person who finds the first cabbage white butterfly of the year in the three-county area of Yolo, Solano and Sacramento receives a pitcher of beer or its equivalent.
Shapiro nabbed the cabbage white butterfly, Pieris rapae, at 1:56 p.m., Thursday, Jan. 19 in the student gardens near the Solano Park Apartments on campus. It's the first time the winner has been found on the main campus.
He found the butterfly, a male, on a cultivated Brassica (cabbage family).
“Earlier today I was asked when P. rapae would come out, given the very wet January this year. I replied that when it stopped raining. we'd probably get into tule fog…and that would take us into February for any decent butterfly weather.”
Jan. 19 dawned with a “a cold, unstable air mass overhead,” Shapiro recalled, describing it as “an ideal convective day, with showers and thundershowers popping up.”
With the ground and the vegetation sopping wet, he figured this would not a “potential rapae day.”
“When I got out of class at noon it was bright and sunny, clear overhead but with cumulus building to the west over the Coast Range. It felt warm and I might have gone to West Sacramento, but decided by the time I got there it would have clouded over and perhaps even be raining. So I got lunch and then walked over to the student gardens near the Solano Park Apartments just to gather host plant for my rapae culture--yes, I'm mass-rearing the bugs for photoperiod studies, and have some 100 live ones in a refrigerator."
“It remained sunny and got quite warm—55 or 56, I'd say," Shapiro related. "The vegetation was indeed sopping wet. At 12:59 I saw—a rapae. It was sitting quietly, wings folded, on a cultivated Brassica. It had not opened its wings to body-bask, that is, warm the body by exposure to incoming solar radiation. If it had, it almost certainly would have flown and, being netless, I would have lost it. Instead it just sat there as I picked it off the plant. I always carry one glasseine envelope in my eyeglass case. Into the envelope it went. It's a winter-phenotype male and, I imagine, had just emerged this morning and not yet flown.”
“This is the second year in a row that the first rapae was found in a garden rather than one of the conventional ‘warm pockets,' Shapiro noted. “What does it all mean?”
The 2016 winner was also found in a garden when UC Davis ecology graduate student Jacob Montgomery stepped outside his home in West Davis on Jan. 16 and collected it.
Davis resident Cindy McReynolds, program manager of the Bruce Hammock lab, UC Davis Department of Entomology and Nematology, spotted some cabbage white butterfly chrysalids in her garden two weeks ago. "They were on the cabbage when I was removing the vegetation."
While scouting for the cabbage white on Jan. 19, Shapiro also noticed a “fresh-looking female West Coast Lady, Vanessa annabella, nectaring at a crucifer in the same garden—first one of those this year too, but it's a hibernator.”
Shapiro launched the contest in 1972 to draw attention to Pieris rapae and its first flight. “Since 1972, the first flight has varied from Jan. 1 to Feb. 22, averaging about Jan. 20.”
The butterfly is emerging earlier and earlier as the regional climate has warmed, said Shapiro, who researches biological responses to climate change. "The cabbage white is now emerging a week or so earlier on average than it did 30 years ago here."
The professor, a fellow of the American Association for the Advancement of Science, the Royal Entomological Society and the California Academy of Sciences, said the cabbage white butterfly inhabits vacant lots, fields and gardens where its host plants, weedy mustards, grow.
Shapiro has won the contest every year except four. The other winners were his own graduate students: Adam Porter defeated him in 1983; and Sherri Graves and Rick VanBuskirk each won in the late 1990s.
Shapiro, who is in the field more than 200 days of the year, monitoring butterflies of central California, knows where to find the cabbage whites. He has collected many of his winners in mustard patches near railroad tracks in West Sacramento, Yolo County. Over the last seven years, five of the winners came from West Sacramento; one in Davis, Yolo County; and one in Suisun, Solano County.
Coincidentally, Shapiro caught the 2013 and 2009 winners on President Obama's Inauguration Day. This year he nearly made President-Elect Donald Trump's Inauguration Day (Jan. 20).
Shapiro maintains a website on butterflies, where he records the population trends. He and artist Tim Manolis co-authored A Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, published in 2007 by the University of California Press.
