Capturing cabbage white butterfly proved impossible
A butterfly for a pitcher of beer is not a fair trade, except in the eyes of Arthur Shapiro, a distinguished professor in the department of evolution and ecology.
Each January for the past 49 years, Shapiro holds a contest between himself and the Davis community to find the first cabbage white butterfly. In his “Beer-for-a-Butterfly” contest, Shapiro promises a pitcher of beer to the first person to capture a Pieris rapae, or cabbage white butterfly in Sacramento, Solano or Yolo counties. And they must capture it before him. For the first time, however, no winner was crowned this year.
Shapiro studies phenology, which is the seasonal timing of biological events. Since 1972, Shapiro has held this contest to track the emergence of cabbage white butterflies as a part of his research. Shapiro picked this butterfly for the contest because it is easy to see and the average person would not have difficulty finding it.
This species finds warm, protected places to stay during the cold months and then emerges when the weather begins warming, usually in January. For most years, the “first flight” of the butterfly is between Jan. 1 to Feb. 22, averaging at the date of Jan. 20. Each year, except for this year, the butterflies emerged earlier. Last year, Shapiro won the contest by finding the first butterfly on Jan. 25, the earliest recorded day in Suisun City in 47 years.
“The idea is that he’s documenting the emergence of these butterflies earlier and earlier as climate changes and weather patterns shift to an earlier warming season,” said Jacob Montgomery, a class of 2017 masters graduate who won the contest in 2016 and currently works as a project manager for California Trout in the Central Valley Region.
In order to win the contest, contestants must capture an adult cabbage white outdoors — no caterpillars or pupae — and deliver it alive to the department of evolution and ecology at 2320 Storer Hall. They must provide the exact time, date and location of the capture with their name, address, phone number and/or email for the data record.
Catchers usually have the best luck finding these butterflies in “vacant lots, fields and gardens where its host plants, weedy mustards, grow,” according to a news release from the department of entomology and nematology.
This year Shapiro saw a female butterfly on Jan. 30 in Winters near Putah Creek, but was unable to capture the specimen. As a result, he extended the contest until 5 p.m. Sunday, Feb. 2, and then again until Monday, Feb. 3, but nobody brought him a butterfly, so he closed the contest. Even though no winner was declared this year, Shapiro still got what he needed: the date of the cabbage white’s first flight of 2020.
“He’s not going to misidentify it,” said Greg Kareofelas, a butterfly expert and volunteer at the Bohart entomology museum. “There’s nothing else he could identify it as.”
Since the start of this contest in 1972, Shapiro has created a large database about cabbage white emergence dates. He has noted that the butterflies have been emerging earlier each year due to hotter weather, making this year an anomaly. Although this was the latest year of capture since 2011, Shapiro said this does not discount the prevalence of global warming.
“When I say that it’s a weird year, it’s because we’ve had very little rain, we’ve had pretty little cold weather,” Kareofelas said. “So even though we’re having kind of nice warm days, and the butterflies should be emerging now, they probably don’t believe that this is truly the time to come out.”
Shaprio believes the reason for this change in butterfly emergence is the lack of colder weather and earlier frost melt, which would cause the butterflies to come out of their winter dormancy sooner. Also, the populations of the butterflies seem to be decreasing, making the probability of seeing one even lower.
“The cabbage white was delayed a little bit this year, but normally they would have come out a little bit earlier than what he first saw, and since he’s first seen it, he hasn’t seen a whole lot more of them,” Kareofelas said.
In the contest, Shapiro has been defeated only four times — all by UC Davis graduate students, according to the news release. Montgomery won in 2016 and Adam Porter, Shapiro’s graduate student, defeated him in 1983. The other two winners were Sherri Graves and Rick Van Buskirk, Shapiro’s former graduate students, who both won the title in the late 1990s.
“People who know about [the contest] are so excited when they hear about it or when somebody wins because that’s like a big deal if you can beat Art Shapiro at his own game,” Montgomery said.
Winners of the contest are brought to the G St. Wunderbar for a celebratory beer with Shapiro, as the original bar of choice, The Graduate, closed. Also, the previous winning beer, Pabst Blue Ribbon (PBR), has been replaced with the new house beer, Hamm’s beer. If an underage student were to win the contest, then they are given the cash value of the beer, Shapiro said.
Before he won, Montgomery had been aware of the contest for many years since he grew up in Davis and attended UC Davis for graduate school. He said he always saw the cabbage white around Davis and the surrounding area as well. And then, on one fateful Saturday morning in January 2016, Montgomery captured his prized butterfly on the way to the Farmer’s Market.
“This butterfly was like sitting in a little bush in our garden on a lavender bush,” Montgomery said. “I just grabbed it and put it inside real quick, and sent off an email. [Shapiro] was asking me to confirm it and send some pictures and videos and confirmed it was the one.”
Montgomery drank a Lost Coast Great White beer, but, to him, the greater prize was the chance to hang out with Shapiro for an hour at The Graduate.
“I mean, the beer’s good, but hanging out with that guy is great,” Montgomery said. “He’s got some amazing stories and just a vast knowledge of these intricacies of relationships and butterflies and flowers and ecosystems.”
Montgomery enjoyed hearing stories from Shapiro’s work where he spends over 200 days a year in the field. The hours Shapiro spends making these observations helps him be an accomplished biologist, and this knowledge is one reason students are drawn to the contest.
“I mean, [Shapiro]’s a legend, right?” Montgomery said. “So if the butterfly legend is telling you ‘I got this butterfly contest,’ you know that has a certain appeal to folks that are interested in that kind of thing.”
Shapiro’s contest is an example of citizen science, as it is a good way to engage the general public yet still provide him with data. For anyone looking to compete in the 2021 Beer-For-A-Butterfly contest, Montgomery’s best advice is to look early and try your luck.
“It’s like anything else,” Montgomery said. “You have to be in the right spot at the right time.”
Written by: Margo Rosenbaum — science@theaggie.org
