This is a seasonal palustrine wetland of the fresh-mixosaline type and constitutes feeding and breeding habitat for over 60 species of resident and migratory water birds, mainly black-bellied tree duck (Dendrocygna autumnalis), roseate spoonbill(Ajaia ajaja), blue-winged teal (Anas discors), limpkin (Aramus guarauna), wood stark (Mycteria Americana) and jabiru (Jabiru mycteria). It is possible to reach it in a four-wheel drive vehicle from the town of Rosario located 6 km from Puerto Humo, on the banks of the Tempisque.