The animal was walking in the "creek sand" and is possible that mud and sand has covered his foot and toes to look like that on film. Try walking in the mud/sand....you will get a layer of gunk on your foot. Notice how the material on his foot also look similar to the color and consistency of the material/sand and mud on the ground.
Saying you can't see toes on the film is not consistent with what it was walking on. If it was hard dirt or grassy plain, then you can use that argument.