Rio La Pasion is located in the Atlantic slope lowlands. The western limit is marked by the Usumacinta river, bordering Chiapas, Mexico.
Rio La Pasion is an important site for 12 species restricted to the Gulf Caribbean Slope. Recent ornithological information is limited to an ecological rapid assessment (AHT 2000) and some additional species records (Eisermann & Avendaño 2007).
BirdLife International (2020) Important Bird Areas factsheet: Rio La Pasion. Downloaded from http://www.birdlife.org on 06/04/2020.