A New Book About Butterflies Makes the Bay Area a More Magical Place

I am not a person that leaves cities if I can possibly help it. I don’t often feel the need to be in nature, and when I do, I visit Lake Merritt or Golden Gate Park. The one time I was forced by a friend to drive through Yosemite National Park — altogether too remote for my liking — I have a recollection of rounding a corner and contemptuously uttering the phrase “Oh good. More trees.”

I mention this so you’ll understand what an enormous feat it is for anyone, anything — let alone a single book — to make me want to start hiking.

But that’s exactly what Liam O’Brien’s new illustrated guide, Butterflies of the Bay Area and (Slightly) Beyond has done. I cannot overstate what a miracle this is. This comprehensive and gorgeous book is so full of reverence for the prettier flying insects in our midst, so lacking in pretension, and so easy to understand, it’ll inspire even the most fervent city-dwellers to get outside and find the little buggers.

If, like me, you need baby steps, that’s okay. O’Brien is clear that one doesn’t have to leave the city to see many of the butterflies he describes in detail. A chapter titled “Tigers on Market Street” is dedicated to the Western Tiger Swallowtails of downtown San Francisco. As O’Brien also explains, the Upper Sunset is the city’s best neighborhood for spotting a variety of beautiful butterflies without leaving the city. But with his cataloging of 135 species from all nine Bay Area counties, plus Mendocino, San Benito and Monterey, don’t be surprised if you start feeling the call of greener spaces.

Though Butterflies of the Bay Area took five years to put together, O’Brien’s first butterfly research began three decades ago, in 1996. One of the reasons his writing doesn’t get bogged down in science-speak is that he’s a former stage actor who spent years performing on major stages, including in Les Miserables on Broadway. His interest in butterflies only intensified after an HIV diagnosis.

“The virus has connected me to nature in a profound and surreal way,” O’Brien writes. “The world of butterflies was handed to me by the fate of the disease. What a blessing. What a gift.”

O’Brien meticulously illustrates each species alongside details of their habitats, host plants and life phases, as well as the best locations to see them. He includes all the scientific information a layperson might need, including a breakdown of official terminologies, the stages of metamorphosis and butterfly migration patterns — but it never gets boring. One section, for example, is titled “On Common Names and Latin Names and the Big Bag of Crazy Those Are.” He uses the word “bazillions” at one point. He even compares butterflies’ preferences for hilltops to humans gravitating towards bars to find a date.

Importantly, there is magic in the ways O’Brien views and describes these insects. Of the Bilateral Gynandromorphisms — butterflies that express both male and female characteristics, possess both sexes’ genitalia and are incapable of mating — he states: “A true chimera roams the earth.”

O’Brien’s calls for more nature conservation are also impactful. “In the early years of this passion for me, one truth became clear,” he writes. “We San Franciscans are more famous for what no longer flies here than for what still does.”

O’Brien was born in Redwood City, raised in south San Jose and is a 30-year resident of San Francisco who has also lived in Benicia. When he offers you a guide to the best butterfly walks in the Bay (and the best times of year to explore them), it’s safe to say you can trust he knows what he’s talking about.

In addition to his own extensive work, O’Brien consulted John Steiner’s lifelong research on butterflies when writing the book, as well as a collection of every male and female butterfly species from Sonoma and Napa that was donated to him by fellow enthusiast Tom Wyndham. Again, the thing that ties that research all together is his ability to make this science relatable. He describes butterflies as “little solar panels.” He describes the minuscule scales on their wings as “laid like overlapping shingles on a roof.” He makes you want to know as much as he does.

In one moving passage, O’Brien describes performing conservation work, including relocating Mission Blue butterflies from San Bruno Mountain to San Francisco’s Twin Peaks. And it’s there that you realize the butterflies are his true calling.

“I have sung alone on a Broadway stage,” he write at one point, “but this job transcends all other experiences. There is a completeness in me here.”

‘Butterflies of the Bay Area and (Slightly) Beyond: An Illustrated Guide,’ by Liam O’Brien, will be released on Sept. 30, 2025 via Heyday Books.