Ecuadorean hummingbird emits high-pitched song from mountains

A species of Ecuadorean hummingbird native to the Andean high-altitude grasslands is unique for emitting the highest sound recorded in birds.

About 14cm (5.5in) long, the Ecuadorean hillstar (Oreotrochilus chimborazo) emits the sound to mark its territory and during courtship rituals.

Experts say they produce a song with a fundamental frequency of 13.4 kHz. This is far beyond the range at which most birds can hear - 2 to 8 kHz.

Their habitat is at an altitude between 3,500m and 5,200m (11,500ft to 17,000ft).

Ecuador, which is rich in biodiversity, is home to 132 hummingbird species out of the more than 300 in the world.