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My previous column about the birds Joseph Grinnell observed on the UC Berkeley campus drew a response from Allison Shultz, a recent graduate who is now the Museum of Vertebrate Zoology’s Centennial Coordinator (more about that below.) Shultz said that for her senior thesis, she replicated surveys done on campus by Margaret Wythe between 1913 and 1927, and by Charles Sibley and Thomas Rodgers in 1938-39. Her results reveal significant changes among those data points. “I saw that the number of species didn’t change much over the years—it actually went up a little—but the community composition changed,” she explains.
Who were these people? Margaret Wythe was co-author, with Grinnell, of the 1927 Directory to the Bird-Life of the San Francisco Bay Region. She started working for Grinnell at the MVZ in 1912, earning 35 cents an hour. After receiving her Master’s degree, she was promoted to Assistant Curator of Birds in 1925. Wythe was on the Museum’s staff at least into the 1940s, when she prepared the distribution maps for The Distribution of the Birds of California by Grinnell and Alden Miller.
Charles Sibley came to Berkeley as an undergraduate in 1937, spent part of his World War II service collecting birds in the Solomon Islands, and returned to UC for his PhD under Miller in 1948. He taught here for a couple of decades before moving to Yale. Sibley, a controversial figure who died in 1998, was on the cutting edge of biochemical studies of the evolutionary relationships of birds. He was the one who determined that New World vultures were actually storks of a sort, and that mynahs and mockingbirds were next of kin. Charles Sibley was not related to field guide author/artist David Sibley.
Thomas L. Rodgers, another of Alden Miller’s students, seems to have been more of a lizard man, although he was the lead author of the article he and Sibley published in the Condor.
As to methods, Wythe kept meticulous notes on the birds she observed for 14 years, using a workman’s time book. “It looks like an Excel spreadsheet,” says Allison Shultz. Sibley and Rodgers monitored birds for a shorter period, and apparently in a more limited area. Their surveys were bounded by Oxford on the west, Hearst on the north, the Campanile on the east, and Allston on the south. They made morning, noon, and evening walks through that area, recording all bird encounters.
Shultz says she tried to mimic what Sibley and Rodgers had done, but using point counts instead of line transects. She also examined old photographs to document changes in landscaping on the campus, and mapped the location of buildings in 1939 versus 2006. Her study ran from October through March, so she may have missed some migrants and summer visitors the earlier study recorded.
Between Wythe’s counts and the Sibley-Rodgers survey, the wrentit—a chaparral-haunting bird, more often heard calling than seen—disappeared from the UC campus. Other species, like the American kestrel, declined. But overall species composition was relatively stable.
From 1939 to 2006, though, there were dramatic changes. New species appeared: Cooper’s hawk, red-shouldered hawk, mourning dove, white-throated swift, Nuttall’s woodpecker, American crow, common raven, chestnut-backed chickadee. These are not all necessarily nesting records, although Shultz suspects the swifts are nesting on some of campus buildings, maybe the Campanile.
And there were losses. Sibley and Rodgers saw California quail on almost half their survey days. That species is completely gone now. So are the American kestrel and American pipit. Shultz also reports the disappearance of the spotted towhee, but my friend John Sutake, a keen observer, recalls seeing them recently when he was UC’s lead groundskeeper; maybe they were missed in the resurvey.
It’s interesting that Shultz found no exotic house sparrows, Eurasian starlings, or rock pigeons in her survey area. “The Cooper’s hawks might keep the pigeons down,” she speculates.
She also had only a few sightings of white-crowned and golden-crowned sparrows, both common winter birds elsewhere in Berkeley.
The gains and losses reflect an altered habitat. “A lot of open area and scrubby places had been removed,” Shultz says. “The Botanical Garden was where Memorial Glade is now until 1924, and some plants were left there until 1960.” Bushes and scrubby areas were removed in the ‘70s and ‘80s for safety reasons. There are also more, and larger, buildings now.
Shultz describes plans for further surveys. In connection with the Museum’s centennial, the Grinnell Project is revisiting Joseph Grinnell’s study transects all over the state. Transects through Lassen Volcanic and Yosemite National Parks have been completed, and show significant patterns of range shifts by small mammals in response to climate change.
If funding is available, the Project will be extended to parts of the Bay Area. “We’ll find qualified observers, have them follow a standard protocol, and enter their observations in an online database,” Shultz explains. Sounds like a great opportunity to get out there with your binoculars and do some Citizen Science. Watch this space for more information.