Clapper Rails are most unwary birds, apparently relying on their habitat of salt grass for cover. This one was sitting in the sun a few feet from the boardwalk at Palo Alto Baylands -- so close to me that at first couldn't get it in the frame with my 400 lens (the big 500 was hopeless.) After quite a while during which I could only get head shots -- http://www.pbase.com/image/71921743 -- the bird moved just far enough away for me to take this one.