Aerie Ouphes' persist ability triggers, returning it from your graveyard to the battlefield.
Aerie Ouphes enters the battlefield, triggering The Great Henge, putting one +1/+1 counter on Aerie Ouphes and causing you to draw a card.
Resolve the Aerie Ouphes ability, dealing damage equal to its power to Swans of Bryn Argoll, causing you to draw cards equal to the damage prevented this way.