The Red-winged Blackbirds and Savannah Sparrows nesting in the tall vegetation south of the Flare Station got a commutation of their death sentence on April 25, when Waterfront Manager Alexandra Endress ordered a halt to mowing in the park.
Endress acted in response to a report by bird expert Rusty Scalf to the effect that Red-winged Blackbirds and Savannah Sparrows appeared to be nesting and breeding in the tract. It is against California law to destroy the habitat of birds while they are breeding, nesting, and raising their young, regardless of whether that habitat is up in trees or down on the ground.
Scalf has taught birding classes through the Golden Gate Audubon Society since 1990, and has conducted Breeding Bird Atlas surveys for a number of California counties, including Alameda.
Visiting the park on Wednesday morning, Scalf not only confirmed that the blackbirds were nesting in the tall grasses and weeds, but also discovered the Savannah Sparrows in the same tract. A subspecies of Savannah Sparrows is listed as a California Species of Special Concern. Both blackbirds and sparrows build nests at ground level or slightly above.
These birds would not nest in vegetation that’s been mowed. If the whole meadow south of the flare station had been mowed in March, the issue of destroying bird habitat would not arise. But only part of the meadow was mowed, and a sizable tract was left to grow. Once the vegetation grew about knee high or taller, it became attractive bird nesting territory, and the birds moved in.
For a copy of Rusty Scalf’s report, along with the cover letter, click here (PDF file). For more on Savannah Sparrows, click here. For the initial post describing the threat to nesting birds in this tract, click here.