Ruddy turnstone is missing feet.

It was dark on the fishing pier at Fort Desoto. The sun had long gone and I was walking back to my car. Even in the dark I noticed this little bird was walking funny. I turned on my flash to shed some light indirectly and found the above ruddy turnstone was missing it's feet. It was still getting around pretty good. I guess the bird has adapted pretty well. I always wonder about these birds. What happened to cause this or was it born without feet? He flew off with no problem.