Part of a Dogshank knot? See also Catshank
The knot shown by OP is nothing more than a bowline with a long bitter end.The bitter end is stored by hitching it around the loop of the bowline-to keep the end from flapping in the breeze? This hitching has no effect on the bowline as far as I can see?
The dogshank is a more secure version of the sheepshank?