The site includes freshwater marshes, reedbeds (Phragmites), riverine forest and cultivated and abandoned fields.
This site is mainly important for reedbed and marshland birds. Species of global conservation concern that do not meet IBA criteria: Crex crex (passage).
BirdLife International (2020) Important Bird Areas factsheet: Marais de L'Ile Vieille. Downloaded from http://www.birdlife.org on 02/12/2020.