Killdeer, Charadrius vociferus
Killdeer, 5/16/06, Palo Alto Baylands
The familiar and distinctive Killdeer looks pretty much the same year round. One variation is that in fresh autumn plumage, they show distinct rufous edgings to the upperpart feathers. These wear off during the winter, giving a gradually more uniform look, though some rufous lining can be retained into summer. The bird on the left has some new and some old feathers, in July.
Killdeer, 8/19/07, Edwards NWR, Alviso
Killdeer,  2/17/07, Edwards NWR, Alviso
Killdeer, 7/16/06, Edwards NWR, Alviso
Killdeer nest on open ground, like the dirt and grass parking lot at Palo Alto Baylands, shown in the three pictures below, including one of nesting and one of copulation.
Killdeer, 4/30/07, Palo Alto Baylands
Killdeer, on nest, 5/12/07, Palo Alto Baylands
Killdeer, pair copulating, 5/24/07, Palo Alto Baylands
Killdeer, juvenile, 10/15/05, Shoreline Park, Mountain View
This bird is molting from juvenile to first basic plumage -- the second chest stripe is just coming in, and buff-lined juvenile feathers, below, are being replaced by adult rufous-lined ones, above.
Killdeer, juvenile, 6/26/06, Cemetery Road, Sierraville, Sierra Co
Left and below are downy chicks, with the single breastband that marks the juvenile Killdeer.
Killdeer, juvenile, 7/23/06, Edwards NWR, Alviso
Killdeer, juvenile, 7/23/06, Edwards NWR, Alviso