International study identifies flight as most efficient vertebrate movement

An international research study published in the journal Science has demonstrated that flight is the most efficient form of movement among vertebrates, challenging the long-held belief that swimming was the most energy-efficient method.

Led by the Max Planck Institute for Animal Behavior and Swansea University, the research team analyzed 17 years of GPS and accelerometer data from 850 birds and bats across 38 species, alongside four years of radar data on small migratory birds. By integrating atmospheric data such as wind and updrafts, researchers were able to calculate the actual energetic cost of flight.

The study distinguished between two primary strategies: continuous flapping and soaring. Soaring birds, such as the Andean condor, utilize updrafts to gain altitude, resulting in transport costs up to 79% lower than birds of similar mass that rely on continuous flapping, such as the trumpeter swan. For instance, while the swan flaps for approximately 99% of its flight time, the Andean condor flaps for only about 0.1% of its time in the air.