The reason their feathers appear shiny green/bronze is due to structural coloration! Instead of having pigments inside their feathers, Nicobar pigeons have tiny nanometer-scale ridges on the surface of their feathers. When light reflects off the feathers, it is distorted in a way that gives them a green/bronze and shiny appearance. Structural coloration is quite common in birds; almost all green and blue feathers are formed this way, but the Nicobar pigeon takes it to a whole new level.

 

Unlike many flocking birds, Nicobar Pigeons are known to fly in columns, sometimes almost in single file. The white tail of mature birds serves as a "taillight" for the bird behind, helping the flock stay together.

 

The female Nicobar pigeon lays a single white egg, which is long and elliptical in shape. The egg is incubated by both adults and hatches after around two and a half weeks. The chick is initially helpless and fed a rich crop milk fluid, regurgitated by the adults, who continue to care for the chick until it fledges at about three months.

 

Nicobar pigeons are classified as Near Threatened on the IUCN Red List. Their population is declining mainly due to habitat destruction. Although illegal capture and hunting are not primary threats due to the pigeon's wide range, they may become more problematic as their habitat diminishes. The presence of introduced predators is another factor harming these pigeons.