On the wing - Whiskered Tern unloads excess baggage

Pooping on the fly -- a tern for the worse, or the ideal weight-loss solution?

In flight, a Whiskered Tern (Chlidonias hybridus) unloads extra baggage by leaving a trail of guano. Defecation in flight probably helps optimise body mass for energy-efficient flight, especially after a bird has recently fed. 

Whiskered Terns may be seen well inland over large water bodies as well as along coasts, estuaries and backwaters. They are strong fliers, with their pointed wing-flaps providing considerable thrust. They twist and turn in flight, changing direction randomly and sweep into the water to emerge with unsuspecting fish, amphibians, crustaceans and aquatic insects in their beaks.

Text and photograph: Sandeep Somasekharan