This swallow is a boreal migrant. It comes to the south to spend summer and goes back to the Northern Hemisphere to breed.
It looks like the Brown-chested Martin but it is smaller. Its tail is relatively short and barely forked, tail undercoverts are long and the collar is very wide laterally. It does not vocalize while on flight. This individual was flying among white-rumped swallows Tachycineta leucorrhoa and brown-chested martins Progne tapera. They were rather high and far.

This swallow is a boreal migrant. It comes to the south to spend summer and goes back to the Northern Hemisphere to breed.
It looks like the brown-chested martin but it is smaller. Its tail is relatively short and barely forked, tail undercoverts are long and the collar is very wide laterally. It does not vocalize while on flight. This individual was flying among white-rumped swallows Tachycineta leucorrhoa and brown-chested martins Progne tapera. They were rather high and far.