Can extirpated quail return to San Francisco parks?

The official bird of San Francisco has become officially extirpated there. But researchers are determined to return California quail to large urban parks in the city, like the Presidio.

“We think that quail potentially could be introduced and they could persist for some time,” said Kelly Iknayan, an environmental scientist with the San Francisco Estuary Institute.

The last California quail (Callipepla californica) was seen in Golden Gate Park in 2018, and in Presidio a few years earlier, despite efforts to save the species, even including designating it as the official bird. The nearest quail population to the city that still persists is in San Bruno Mountain, an open space to the southeast of San Francisco.

In a study published recently in the Journal of Applied Ecology on factors that are important for quail population presence and persistence, Iknayan and her colleagues found that in areas closer to urbanization, these birds need large, open space to survive. “Size was a big factor in whether or not they persist,” she said.

The results indicated that improving habitat connectivity between parks is likely an important factor for ensuring long-term survival of populations, Iknayan said. Work like the Great Highway Project that closes parts of a coastal highway in the city are improving connectivity already.

The researchers also found that coyote (Canis latrans) presence was positively associated with quail presence. It’s unclear why this is the case, but Iknayan said that coyotes might play a role in suppressing the populations of smaller mesocarnivores that prey on quail like feral cats (Felis catus) and raccoons (Procyon lotor). Or the presence of coyotes may just dissuade cats and raccoons from using the open spaces, opening up areas that quail prefer.

Researchers aren’t sure why quail were extirpated from San Francisco parks, but predation by raccoons and feral cats, both of which are relatively tolerant of humans, may have contributed to their disappearance. Coyotes weren’t present in Golden Gate or Presidio park until more recent years, by which time the quail were already pretty low in numbers or gone altogether.

Another factor that led to the extirpation of California quail in both parks is likely their isolation. Regardless of the reasons that numbers dropped in these parks, populations would have been hard put to recover due to the lack of immigration from outside populations.

Restoration of native shrubs and other plants as well as improvements to waterways might also improve the ecosystem for quail, the team found.

Overall, these kinds of changes can hopefully improve urban parks for the eventual return of the birds, Iknayan said. Presidio Park staff have already successfully reintroduced several species such as western fence lizards (Sceloporus occidentalis) and California ringlet butterflies (Coenonympha tullia).

“We can start to look at how we can make changes and improve the landscape so that some of these species can come back,” she said.