Red-winged Blackbirds and Savannah Sparrows are doing it. At least two pairs of House Finches are doing it, too, up in the northwestern quadrant, wing to wing with the blackbirds. They’re nesting.
As this short video opens, a Red-winged Blackbird female perches in the upper left on top of a bush, with two male House Finches and one female House Finch next to her. I saw these finches plus another one or two females fly off repeatedly into nearby grasses and onto dirt, picking up items of interest and flying back into the bush. At one point, a female with her beak full of nesting material approaches a male, who promptly chases her away. Hmm.
I had thought that these finches did their breeding somewhere else and only came here for the winter, often in flocks of hundreds. But apparently at least a small handful have decided, the heck with that, let’s just stay here. Who could blame them?