The Sanctuary’s most representative ecosystem is its coastal lagoons: Navío Quebrado lagoon and Laguna Grande. Both are very important socially, economically and culturally as well as providing a great many environmental goods and services. The area also has relics of dry and very dry tropical forest and mangrove forest ecosystems, the latter directly associated to the coastal lagoons, containing estuaries that are habitat to an important biological community composed mainly of crustaceans, mollusks and fish.