This goose is actually not all that alone. To the left beyond the image are about 30 of them swimming away. This goose looked like s/he was quite happy having some time away from the flock. About 5 minutes later, s/he started paddling over to catch up to the group.
The composition is spot on, as is the processing - I've been sitting here staring at for quite some time and the only thing I'm disappointed with is that no monster from the depth s has erupted from the water to devour that goose. Other than that, fabulous.
@graemestevens Ah...but it's there...just off camera. Remember the 30 other geese I mentioned? There weren't 30 by the time this one arrived over there.
She does seem to be looking back, just to check that she isn't completely out of touch. The way the sun shines over the water giving that strong strip of light balances your composition so well.