A Brief Treatment of Harpies

First identified in ancient Greek and Roman study, harpies (Greek: ἅρπυια, harpyia, pronounced [hárpyi̯a]; Latin: harpȳia) are female monsters in the form of a bird with a human face. In myth, they are said to steal food from their victims while they are eating and carry evildoers (especially those who have killed their family) to the Erinyes. They seem originally to have been wind spirits. Their name means “snatchers.”

“Debate rages on whether these creatures are full on Chimera, escapees of a Horizon or Spirit Realm, or naturally occurring albeit rare Earth inhabitants... Harpy claws are often used in the casting of destructive magic for their razor sharp qualities... Should be flightless due to poor aerodynamics, but nonetheless can remain airborne even in storm weather... Do not bear full human cognitive abilities, but nonetheless communicate, hold social structure, use primitive tools, and can build simple structures. They show memory capabilities, and logical and deductive capabilities... Harpy eggs are nearly beyond value, as a harpy raised from birth tends to be loyal and protective. The Fae desire such creatures as companions, and capable wizards might utilize them as Familiars. To the ruthless, the eggs have an ability to ‘appease’ Paradox when destroyed...” Godric's Tome of Beasts and Intellects, Adept Life, Order of Hermes

Supposedly all harpies hail their Queen Stizzexa, though whether she actually exists or is a myth, or in what capacity she exists is unknown outside of harpies. Her Domains are Wind, Mothers, and Nature. They tend to be territorial and fend off intruders almost on sight. They can be bribed by a sufficiently humble intruder. They prefer diets of fish and fruits. They lay eggs, which must be cared for from 6-7 months. Harpy young can fly within a week of birth. Harpies roost in high, defensible points, preferring difficulty to access to stealthy locations. Some harpies, but not all, have demonstrated the ability to learn mortal languages, though they rarely speak them eloquently. Most harpies have impressive strength and inflict wounds that penetrate most armors and are very hard to heal, and are mostly immune to weather conditions be they natural or magical.

Harpies have figured into the imagination of various cultures. For instance, Dante refers to harpies in his descriptions of hell:

Here the repellent harpies make their nests,

Who drove the Trojans from the Strophades
With dire announcements of the coming woe.
They have broad wings, with razor sharp talons and a human neck and face,

Clawed feet and swollen, feathered bellies; they caw
Their lamentations in the eerie trees

The harpy may or may not be related to other creatures of myth and legend, including the Russian Alkonost and Sirin, the Japanese Karura and Tengu, and the south east Asian Kinnara.

Full treatment of their role in Greek Poetry
(From http://www.theoi.com/Pontios/Harpyiai.html)

Harpies, “the swift robbers,” are, in the Homeric poems, nothing but personified storm winds. (Od. xx. 66, 77.) Homer mentions only one by name, viz. Podarge, who was married to Zephyrus, and gave birth to the two horses of Achilles, Xanthus and Balius. (Il. xvi. 149, &c.) When a person suddenly disappeared from the earth, it was said that he had been carried off by the Harpies (Od. i. 241, xiv. 371); thus, they carried off the daughters of king Pandareus, and gave them as servants to the Erinnyes. (Od. xx. 78.) According to Hesiod (Theog. 267, &c.), the Harpies were the daughters of Thaumas by the Oceanid Electra, fair-locked and winged maidens, who surpassed winds and birds in the rapidity of their flight. Their names in Hesiod are Aëllo and Ocypete. (Comp. Apollod. i. 2. § 6.) But even as early as the time of Aeschylus (Eum. 50), they are described as ugly creatures with wings, and later writers carry their notions of the Harpies so far as to represent them as most disgusting monsters.

They were sent by the gods as a punishment to harass the blind Phineus, and whenever a meal was placed before him, they darted down from the air and carried it off; later writers add, that they either devoured the food themselves, or that they dirtied it by dropping upon it some stinking substance, so as to render it unfit to be eaten. They are further described in these later accounts as birds with the heads of maidens, with long claws on their hands, and with faces pale with hunger. (Virg. Aen. iii. 216, &c.; Tzetz. ad Lycoph. 653; Ov. Met. vii.4, Fast. vi. 132; Hygin. Fab. 14.) The traditions about their parentage likewise differ in the different traditions, for some called them the daughters of Pontus (or Poseidon) and Terra (Serv. ad Aen. iii. 241), of Typhon (Val. Flacc iv. 428, 516), or even of Phineus. (Tzetz. ad Lycoph. 166, Chil. i. 220; Palaephat. 23. 3). Their number is either two, as in Hesiod and Apollodorus, or three; but their names are not the same in all writers, and, besides those already mentioned, we find Aëllopos, Nicothoë, Ocythoë, Ocypode, Celaeno, Acholoë. (Apollod. i. 9, 21; Serv. ad Aen. iii. 209; Hygin. Fab. Praef. p. 15, Fab. 14.) Their place of abode is either the islands called Strophades (Virg. Aen. iii. 210), a place at the entrance of Orcus (vi. 289), or a cave in Crete. (Apollon. Rhod. ii. 298.)

The most celebrated story in which the Harpies play a part is that of Phineus, at whose residence the Argonauts arrived while he was plagued by the monsters. He promised to instruct them respecting the course they had to take, if they would deliver him from the Harpies. When the food for Phineus was laid out on a table, the Harpies immediately came, and were attacked by the Boreades, Zetes and Calais, who were among the Argonauts, and provided with wings. According to an ancient oracle, the Harpies were to perish by the hands of the Boreades, but the latter were to die if they could not overtake the Harpies. The latter fled, but one fell into the river Tigris, which was hence called Harpys, and the other reached the Echinades, and as she never returned, the islands were called Strophades. But being worn out with fatigue, she fell down simultaneously with her pursuer; and, as they promised no further to molest Phineus, the two Harpies were not deprived of their lives. (Apollod. i. 9. § 21.) According to others, the Boreades were on the point of killing the Harpies, when Iris or Hermes appeared, and commanded the conquerors to set them free, or both the Harpies as well as the Boreades died. (Schol. ad Apollon. Rhod. i. 286, 297; Tzetz. Chil. i. 217.) In the famous Harpy monument recently brought from Lycia to this country, the Harpies are represented in the act of carrying off the daughters of Pandareus.

Note: Harpies share their name with the role of rumor monger in certain covert societies.