Josiah Clark’s talk was an excellent wrap up to our year. Josiah’s work as an ecologist focuses on where the wild can fit into our urban centers. How we can take the highly fragmented green spaces of our cities and make them resilient and sustainable for the “last of the least and the best of the rest.”
The most fundamental aspect of that work is making these green spaces functional breeding areas. Keys to this is to have a lot of biodiversity (both of species and within species), and building up native plant communities, where communities is the operative word. Complex mashups of plants create all the more opportunities for all sorts of wildlife to thrive.
But each different area even within such a small city as San Francisco, can often need different management strategies. These strategies often hinge on understanding what the disturbance regimes (erosion, wind, floods, and nutrients) are like in a given area: for instance high tides at Crissy fields, fires (or the lack thereof) on San Bruno mountain, or wind blown dunes. Areas like dunes, serpentine and bluffs have poor nutrient soils, but because of their limits, often leaves native plants with better chances. Often times those disturbance regimes are the things that native plants were adapted to, and humans having built up or mitigated their affects has been to the detriment of native plants (like fire adapted coastal scrub). Our last remaining native rodent the gopher even provides positive disturbance, creating erosion where it otherwise would not happen.
Josiah then led us through a few case studies: the Green Hairstreak Project, Nutall’s White Crowned Sparrow in the Bison paddock of Golden Gate Park, and the Pacific Chorus Frog. And how these were managed with all these things in mind.
And speakers have been bringing to us other examples of this all year long: Liam O’Brien talking on restoring the mission blue, Matthew Bettelheim and the western pond turtle, Brent Plater and Sharp park, John Bourgeois and salt pond restoration, our speakers on Yerba Buena island, Vance T. Vredenburg on frogs in the Sierras, and Camilla Fox showing us Coyotes in the city. We also had two historical overviews of the process of how our city came to its current fragmentation of habitats: one local — Joel Pomerantz and the Wiggle, once stream now bicycle route — and one area wide, Professor Richard Walker, giving us a history of bay area environmentalism.
We look forward to what we can bring out for you in 2011.
SF Natural History Series 