[Mystery bird] The White Tern is known by more alternate names than a con-artist, also being known as the Angel Tern, Common White-tern, Common White Tern, Little White Tern, Little Fairy Tern, Fairy Tern, Little White-tern, Little Fairy-tern, and even (since it lives in tropical oceans of the world) as the Atlantic White Tern, Gygis alba (formerly; Gygis microrhyncha), photographed on Midway Atoll National Wildlife Refuge — one of the most remote coral atolls on earth — a US territory in the north Pacific Ocean [I will identify this bird for you in 48 hours]
NOTE: Please name at least one field mark that supports your identification.
This wide-ranging and stunningly beautiful mystery bird is famous for a unique and astonishing behavior — what is this behavior?
This small tern is famous for laying its egg on bare thin branches in a small fork or depression of a tree or bush. This balancing act is probably a predator-avoidance behavior as the branches they choose are too small for rats or even small lizards to climb (although I was intrigued by several commenters’ observation that this is a way to avoid insect/arachnid nest parasites). White Terns are also quick to relay should they lose the egg in a windstorm. Newly hatched chicks have well developed feet that they use to hang on to their precarious “nest.”