I recently discovered surfbirds (Aphriza virgata) with the help of a local birding group. Unless you’re looking for them,
or watching rocks and one happens by, they’re hard to spot. I’ve seen them at the surfline on Monterey’s Coast Guard breakwater and along our rocky shores. They’re small, stocky gray birds (I know, non-descript) and easy to confuse with turnstones, which share the same space, however surfbirds have yellow legs.
Scientists have had a tough time classifying surfbirds. They’re in their own genus in the sandpiper family (Scolopacidae). But there’s question about whether or not that’s right. They’re viewed as an intermediate between turnstones (genus Arenaria) and knots (genus Calidris) with characteristics of both (Livezey 2010). Some think that they may be more closely related to knots.
Along Monterey Bay, most surfbirds are winter visitors (although some stay on as residents according to the SIMoN species database). They actually winter along the shore from Alaska to Chile. I’m not sure why I’ve never noticed them before, maybe not paying attention or mistaking them for turnstones (this photo shows a surfbird in front of a turnstone — they do look different when side-by-side). 
Like turnstones, surfbirds dodge the surf while probing rocks for molluscs (snails, barnacles, etc.) and crustaceans (crabs, etc.) The Cornell Lab All about Birds site says they pull up mussels and barnacles and swallow them whole (one wonders how the rest of the digestive process goes).
I admire anything that can make a living in the intertidal, especially along the surfline. It’s a physically rough place. These small, tough birds, amid the raucous sea lions and gulls, are interesting to watch when you can find them.
WordCraft.NatureFocus 