Semipalmated Plovers (Charadrius semipalmatus) are common winter residents and spring/fall migrants in the Bodega Bay area. You can find them in Bodega Harbor during low tides and on the outer beaches during high tides. These photos are from Salmon Creek Beach on 8 March 2012.
Although not often visible, Semipalmated Plovers are named for their partially webbed feet. More noticeable field marks include a short dark bill, often with orange at the base; a white collar and single dark breast band; orange-yellow legs; medium brown above and bright white below.
Note that Snowy Plovers are lighter above (more gray than brown) and have black or gray legs (for comparison, see below and post on 3 December 2011).
Today I tried to take some photos of Semipalmated Plovers in flight. The photos could be sharper (it's difficult to follow them in flight!) , but they still seemed interesting for a different view of this species. Here are two from above and two from below (click to enlarge).
Note the long narrow wings and somewhat falcon-like profile. Shorebirds are known for their fast flight, and Semipalmated Plovers are no exception. They've been recorded flying at 52 km (32 mi)/hour!
(P.S. You may have noticed another species in the photographs. There were a few Dunlin mixed in with these Semipalmated Plovers. There's at least one Dunlin (and up to three) in every photo of the flock in flight — look for the all brown head and longer bill.)