The Stymphalian birds (Ancient Greek: Στυμφαλίδες ὄρνιθες) are a flock of voracious, man-eating birds in Greek mythology, named for their dwelling in the swamp of Stymphalia in Arcadia. They were credited with bronze beaks, sharp metallic feathers they could launch like darts, and poisonous excrement. Clearing them from the marsh was the sixth labour of Heracles, who scared them aloft with a bronze rattle given by Athena and shot them with arrows poisoned by the Hydra's blood. The survivors are said to have fled to the island of Aretias in the Euxine Sea, where the Argonauts later encountered them.
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I.Characteristics
The Stymphalian birds were described as creatures of formidable, destructive equipment: bronze beaks, sharp metallic feathers they could launch as weapons, and poisonous excrement.
According to Pausanias, the birds flew against those who came to hunt them, wounding and killing them with their beaks. All armour of bronze or iron that men wear could be pierced by the birds; the one effective defence was a garment woven of thick cork, in which the birds' beaks would become caught and entangled. In size and form they resembled cranes and were like the ibis, but with more powerful beaks.
II.Mythology
The birds had divine connections in the tradition: they were said either to be the pets of Artemis, goddess of the hunt, or to have been brought up by Ares, god of war. They migrated to an Arcadian marsh to escape a pack of wolves, where they bred quickly and swarmed over the countryside, destroying crops, fruit trees, and the townspeople themselves.
III.The Sixth Labour of Heracles
Driving the birds away from the marsh was the sixth labour that Eurystheus set for Heracles. The terrain itself obstructed him, for the marshy ground would not support his weight and he could not approach the flock on foot.
Athena came to his aid, providing a rattle called the krotala, which Hephaestus had made especially for the occasion. By shaking the rattle, Heracles frightened the birds into the air; he then shot many of them with feathered arrows tipped with the poisonous blood of the slain Hydra. The surviving birds flew far away, never to plague Arcadia again, and settled on the island of Aretias in the Euxine Sea, where the Argonauts later encountered them.
An alternative version, attributed to Mnaseas, claimed that they were not birds at all but women, the daughters of Stymphalus and Ornis, whom Heracles killed for their inhospitality. A temple nevertheless represented them as birds, and behind it stood white marble statues of maidens with the legs of birds.
IV.Classical literature sources
The Stymphalian birds are documented across an extensive range of ancient authors, from the 5th century BC through the Byzantine era. Greek and Roman writers who record the birds and the labour of Heracles include Sophocles, Apollonius Rhodius, Pausanias, Ovid, and Seneca, among many others, down to the twelfth-century scholar Tzetzes.