No one has come forth with the first cabbage white butterfly, Pieris rapae, of the year in the three-county area of Sacramento, Yolo and Solano, to win the 2026 Beer-for-a-Butterfly Contest.
Not even the sponsor, UC Davis Distinguished Professor Emeritus Art Shapiro, who launched the event in 1972--and who usually collects the winning butterfly and the beer.
It works like this: collect a live rapae in the wild in the three-county area. Then contact Shapiro at amshapiro@ucdavis.edu or theochila@gmail.com to see if you're the winner. The prize: a pitcher of beer or an alternative drink. Suds for a bug...
"After 0.01" of rain overnight, today dawned bright and sunny with a few scattered cirrus and a few early-morning cumulus that evaporated quickly," he emailed to his posse today. "I went to North Sac. 61F, wind N 6-12 mph, 95% sun. It only felt warm in S-facing wind-sheltered spots, where I saw 1 each, atalanta (Vanessa atalanta, the red admiral butterfly) and antiopa (Nymphalis antiopa, the mourning cloak). Still no rapae! The suspense is killing me..."
The point of the contest "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.
So what day were the winning cabbage whites collected over the last 10 years?
- 2025: Art Shapiro collected the winner at 12:13 p.m., Jan. 23 in West Sacramento, Yolo County
- 2024: Art Shapiro recorded the winner at 11:30 a.m., Jan. 29 in West Sacramento, Yolo County
- 2023: Shapiro recorded the winner at 11:22 a.m., Feb. 18 in West Sacramento.
- 2022: No official contest due to the COVID pandemic, but Shapiro recorded his first-of-the-year P. rapae at 1:25 p.m. on Jan. 19 in West Sacramento
- 2021: No official contest due to the COVID pandemic, but Shapiro collected his first-of-the-year at 1:55 p.m. Jan. 16 on the UC Davis campus, Yolo County
- 2020: Shapiro recorded the winner in Winters, Yolo County at 11:16 a.m. on Jan. 30 at the Putah Creek Nature Park.
- 2019: Shapiro collected the winner near the Suisun Yacht Club, Suisun City, Solano County, at 1:12 p.m., Friday, Jan. 25.
- 2018: Shapiro collected the winner in West Sacramento
- 2017: Jan. 19: Shapiro collected the winner on the UC Davis campus
- 2016: Jan. 16: UC Davis graduate student Jacob Montgomery collected the winner in west Davis
Shapiro has been defeated only four times, and all four were graduate students.
Meanwhile, we're running out of January, and the suspense is killing Art Shapiro. As you know, he knows where to look. He's an internationally recognized lepidopterist who has been monitoring the butterfly populations of central and northern California since 1972. He maintains a research website at https://butterfly.ucdavis.edu/. (By the way he's featured in the current issue of Vacaville Magazine).
Isn't it time for you to head out with your net and collect that live butterfly and win bragging rights and a beer? P. rapae inhabits vacant lots, fields and gardens where its host plants in the mustard family (Brassicaceae) grow. Hosts include cultivated vegetables like cabbage, broccoli, cauliflower, kale, Brussels sprouts, collards, and mustard greens.
Cover image: Cabbage white butterfly, Pieris rapae. (Photo by Kathy Keatley Garvey)