I was watching a semi-palmated plover when out of the corner of my eye a Merlin is observed flying around. I look back at the plover but it seem to have disappeared. I didn't see it fly away. I kept scanning the sand and finally saw this mark in the sand as my eyes adjusted. It was the plover trying to camouflage itself by flattening its body against the sand. It worked. The merlin continued to fly around but eventually left.