Of Cows, Cars, and Checkerspots

January 15, 2015

Stuart Weiss, co-founder of the Menlo Park-based environmental consulting firm Creekside Center for Earth Observation, is one of those rare birds who’s managed to connect hard science to on-the-ground conservation on a grand scale. And he started out by just doing what he loves: chasing butterflies!

Are you originally from the Bay Area? If not, what brought you here?
I’m originally from suburban Philadelphia. I got accepted at Stanford and chose it over Harvard because I wanted to come to California: The Grateful Dead and the allure of San Francisco drew me out here. Also, I hadn’t done very much travelling, and coming out here gave me the chance to see things on the way, like the mountains of the West, which had been such mythical places to me.

What got you into the field of environmental science?
I was 10 years old on the first Earth Day in 1970 and it made a huge impression on me. My dad was an anti-war activist, and I have that tradition in my family: Find a way to make the world a better place. It’s amazing to recall how foul the air and water were back then — there was such an obvious need for a cleanup. I also wanted to work outdoors.

What is Creekside Science? When did you start the firm and why?
After I graduated with a BS in Biology I got a research assistant position at Stanford at the same lab I’d worked at in college. In 1992 I started a Ph.D. program, worked as a post-doc, and was finally fledged from the academic nest in 1998. I’d been doing consulting work on the side for many years and I started striking out on my own. I picked up a few large environmental consulting contracts and learned how to hustle and make it work. In 2006, I formally named my consulting shop the Creekside Center for Earth Observation. Now I have three staff people, and we get to do a lot of really interesting work.

Like what?
The really interesting one I inherited from Paul Ehrlich’s lab at Stanford is studying the Bay checkerspot butterfly to help conserve populations threatened by human impacts. I’ve been working on it since 1979. We started studying the “Mother Lode” population at Coyote Ridge south of San Jose in 1984. It’s led to a lot of on-the-ground conservation; for example, we successfully defended a natural preserve (Edgewood Preserve in Redwood City), which is home to the checkerspot’s preferred habitat, from becoming a golf course in the late 80s and early 90s.

Related to that work, in 1999 I published a paper in the journal Conservation Biology entitled “Cars, Cows, and Checkerspot Butterflies”. That paper has led to about $700 million in mitigation funds going to conserve the butterfly’s habitat as part of the Santa Clara Valley Habitat Plan. It took nearly 15 years of work with a lot of people, combining science with grassroots rabble-rousing, to make it happen.

The rare Bay checkerspot butterfly prefers serpentine soils, which are themselves a threatened habitat. Photo: Stu Weiss
The rare Bay checkerspot butterfly prefers serpentine soils, a threatened habitat. Photo: Stu Weiss

The link between these three “C’s” – cars, cows, and checkerspots – is a phenomenon you call “chemical climate change”. What does this term mean, and how has it impacted species like the checkerspot?
The reactive nitrogen we spew into the air from our cars and trucks and industry (what scientists call “nitrogen deposition”) has changed the atmosphere into a potent fertilizer. It’s like dumping bags of the stuff onto our soils; San Jose is getting up to 20 pounds of nitrogen per acre per year. It’s far beyond the historical range, and it makes invasive grasses and weeds grow like crazy, so they overwhelm the small native wildflowers that the Bay checkerspot needs to survive. I call it the biggest global environmental change we’ve never heard of. Even Sonoma County has some of the highest nitrogen deposition in the Bay Area.

What can be done about it?
California’s nitrogen levels have dropped by half since the 1980s, thanks to our strict pollution control laws. But the land itself has been saturated by nitrogen for a long time now. Cleaning it up will take decades. The good news is that it can be managed by cattle grazing – all cows eat grass. Without the cows, there wouldn’t be checkerspot butterflies.

How did you convince officials involved in the project to preserve butterfly habitat on the side of a major highway?
I got to take a lot of Santa Clara County supervisors and other local politicians on tours through the wildflowers. Driving down 101 you’d think it’s just a big barren hillside up there on the east side. But that first ridge east of the highway is covered with wildflowers in the spring, and hundreds of thousands—even millions—of Bay checkerspots are flying around.

What about your work to restore wintering monarch butterflies ?
In 1999 I worked on a restoration plan in Pacific Grove, “Butterfly Town USA”. The forest canopy was falling apart, so we planted an additional row of bluegum eucalyptus trees to protect the site from northwest winds. 15 years later the trees are 60 feet tall and they’re providing wind shelter and monarchs have moved into the area.

You’ve got to be in this kind of restoration work for the long haul. It takes a decade to make it work. You’ve got to figure it out as you go along.

What inspired you to spend a good part of your career trying to understand and preserve butterflies?
When I came to Stanford I was chasing butterflies on Jasper Ridge as a work-study job while my friends were sitting in a lecture hall for Econ 1. I thought this was much better. Chasing butterflies through fields of wildflowers gets kind of addicting and doing it for a good cause is pretty satisfying. We get to see the results of our work and land being conserved and managed.

Stu working in the monarch butterfly habitat at Pacific Grove, CA. Photo: Lech Naumovich
Stu working high up in the monarch butterfly habitat at Pacific Grove, CA. Photo: Lech Naumovich

What’s your favorite habitat?
What I really like is the complex mosaic of habitats in the Bay Area; on one side of the ridge you can have dry chaparral, and on the other slope is redwood forest. That’s really the key to many species’ resiliency under climate change: We have this complex topography and coastal inland temperature gradient. Local topography lets some butterflies survive in a dry year—they can escape to north-facing slopes where there’s more moisture. Then when conditions improve, the populations spread out again across habitats.

What do you think is the most endangered native habitat type in the Bay Area? And what should be doing to try to preserve it?
At the top of my list would be native grasslands and vernal pools. And what we need to do to save them is support a really strong Endangered Species Act. That’s a very powerful law that can be applied to preserve these habitats – and we need to support the Bay Area Conservation Lands Network. That gives us the ability to manage the habitats.

Where do you like to roam on your days off?
I never really have a day off, because I work for myself. But almost anywhere, really. I love going to the beach: Pescadero — places with good tidepools and rocky shores, like the Fitzgerald Marine Reserve. I also love the Monterey Peninsula.

>> Learn more about Stu’s current projects: visit the Creekside Center for Earth Observation.

>> Stu presented a workshop on nitrogen deposition at the California Native Plant Society’s 2015 Conservation Conference this week. Learn more about upcoming speakers and exhibits at this year’s conference in San Jose, running through Sunday, January 18th.

About the Author

Beth Slatkin is Bay Nature's marketing and outreach director.

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