I was perusing the U.S. Copyright Office FAQ and came across this paragraph:

How do I protect my sighting of Elvis?
Copyright law does not protect sightings. However, copyright law will protect your photo (or other depiction) of your sighting of Elvis. Just send it to us with a Form VA application and the $30 filing fee. No one can lawfully use your photo of your sighting, although someone else may file his own photo of his sighting. Copyright law protects the original photograph, not the subject of the photograph.