So there is a mythical creature called a harpy, who was a half woman, half bird.
Anything on what type of bird it was?
I'm not aware of any specific species being mentioned in the myths.
Traditional depictions generally seems to have considered the bird part to be some kind of bird of prey (given the size and the claws).
Further, given their nature as befouling creatures, I'd expect some kind of scavenger bird, like a vulture or buzzard.
In this classical depiction they are simply women with wings:
Actually, rather like angels in Christian iconography.
considering that in most media forms, harpies have a pretty humanlike-posture, I mean they mostly have their backs straight. considering they always are depicted as meat eaters and very territorial, I would consider them being close to the eagle.
being eagle based can also explain why some say that harpies live in mountains or near oceans. since there are subspecies of eagles who live inland while other subspecies live near large bodies of water other predator birds like buzzards and falcons havený such a diverse diet. they probably aren't based on owls since owls have plumage on their legs, and most other birds don't.