Flying Swallow, Leaping Tiger

When a team of scientists set out to study the African Tigerfish (Hydrocynus vittatus) in a South African lake, they took some of the more colourful local rumours about the fish’s hunting behaviour with a pinch of salt. But their healthy scepticism was quickly dispelled when they made the first confirmed record of a freshwater fish preying on birds in flight. 

The attacks happen astoundingly quickly, with the fish leaping clear of the water to catch the swallows in mid-air, and during their time at the lake, researchers saw as many as twenty successful strikes a day on fast-flying barn swallows that skimmed too near the water’s surface. Yet the feat is made even more impressive by the fact that the barn swallow is a famously agile species that can fly at speeds of up to 40mph

While other fish such as Bass, eels, piranhas and pike have all been known to occasionally eat birds, they tend to prey on stationary targets floating on the surface or by the water's edge. For example, the European catfish has been spotted leaping onto shores to catch pigeons. But this is the first definitive proof of a freshwater species preying on birds in flight, and scientists believe the behaviour may have been adopted out of necessity because of limited food supplies in the Tigerfish's habitat.

However the tactic, while spectacular, is a risky one. By attacking barn swallows in the air, the African Tigerfish leaves itself vulnerable to other, more fearsome airborne predators itself, such as the African fish eagle.