There they bred quickly and swarmed over the countryside, destroying crops, fruit trees, and townspeople.

Athena, noticing the hero's plight, gave Heracles a rattle called krotala, which Hephaestus had made especially for the occasion.

Heracles shook the krotala (similar to castanets) on a certain mountain that overhung the lake and thus frightening the birds into the air.

According to Mnaseas,[11] they were not birds, but women and daughters of Stymphalus and Ornis, and were killed by Heracles because they did not receive him hospitably.

[12] Chronological listing of the main classical literature sources for the Stymphalian birds (not comprehensive): Regarding the Sophocles source, Jebb[13] says Brunck[14] reads "πτωκάδες" as "πλωάδες" which is an epithet given by Apollonius Rhodius to the Stymphalian birds in Argonautica 2.