The nonbreeding Forster’s Tern in these two images is the same bird and the images were taken ten frames and a few seconds apart as the tern stood on the shoreline of the Gulf of Mexico in Florida.
When photographing birds on the shoreline when there are waves just a few seconds can really make a difference in the background. In the top image the wave had just barely begun to break while in the second image the wave had crested which gave the background lighter colors plus it gave the sand under the bird a glassy look where the wave had washed on shore.
Just a few seconds can make a difference.
MiaAdditional posts you might enjoy: