Effects of fishing on the structure and functioning of estuarine and nearshore ecosystems

TLDR

Estuaries are economically valuable fisheries habitats that are heavily modified and threatened by human activities, including fishing. The study synthesizes global effects of fishing on estuarine and coastal waters. The authors review eight process‑oriented categories—target organisms, non‑target organisms, nursery functions, trophic effects, habitat change, reduced water quality, human environment, and potential local extinctions—using case studies. The interactions among these factors underscore the need for integrated coastal management and suggest that fish‑based action plans could be developed for estuaries.

Abstract

Estuaries and associated coastal waters support many essential fisheries, a fact which contributes to their disproportionately high economic value. They are, however, also among the most extensively modified and threatened of aquatic environments. Almost all have been strongly affected by human beings, and fisheries are an integral part of human activities on the coast. We have taken a global perspective in synthesizing the effects of fishing on estuaries and coastal waters. Rather than attempt to cover all regions of the world in detail, we review eight process-orientated categories affected by fishing, with case studies for each of them: target organisms, non-target organisms, nursery functions, trophic effects, habitat change, reduced water quality, human environment, and potential for local extinctions. Fishing in the estuarine and nearshore environment has clear impacts on the structure and functioning of these ecosystems, although other, non-fishing issues also effect these ecosystems. This creates multiple interactions and reinforces the need for an integrated approach to coastal zone management. Nonetheless, some form of fish-based action plan could be created, especially within estuaries, which would provide management objectives for a particular system.