A review of amphidromous freshwater fishes of the Chocó biogeographical region (Colombia and Ecuador): diversity, ecology, fisheries and conservation
Amphidromy is a specialized form of diadromy developed by tropical and temperate fish and invertebrates. In the tropics, most amphidromous fish belong to the Gobiidae and Eleotridae families. Knowledge on the taxonomy, phylogenetics, ecology, fisheries and conservation of this group of fishes has been gathered in the last 30 years mainly in the Indo-Pacific and Caribbean regions, with the tropical Eastern Pacific region largely overlooked in literature. Here, we provide a state of the art review on the ecology, fisheries and conservation of amphidromous fishes in two countries of the Chocó biogeographical region (Colombia and Ecuador). We then focus on different observations carried during the last 10 years at three main localities (El Valle – Chocó, Delta del Rio San Juan and Dagua Basin) with contrasting environmental settings in the Colombian Pacific coast where amphidromous fishes are harvested by Afro-Colombians and Indigenous people. Accelerated environmental changes (e.g. mining, deforestation, water pollution) in the catchment areas of the rivers draining into the Pacific Ocean may threaten the populations of several of these amphidromous fishes. Understanding further ecological aspects of amphidromous fishes in this region will greatly benefit further global comparisons.