I have seen similar behaviour with a S E Owl some years ago and as well as the headwind, it was pestered by gulls. Now I have also seen a Merlin a short distance off shore waiting on and then following in a tired pipit to nail it just as it crossed the coast, presumably not to be harassed by gulls for its prey too far out to sea.
Perhaps these owls do the same at night too, and you happened to witnessed the performance in day light .
Other views anyone?
Seen three dead a.ll road casualties, with in one week . two on the a19,one on the a689,I guess, bit of an influx.
Some asio owls at Flamborough today doing the same over the sea.