The Importance of Pinnacles and Seamounts to Pelagic Fishes and Fisheries off the Southern Baja California Peninsula

Abstract

We evaluate the importance of seamounts to pelagic fishes and fisheries in the Gulf of California by creating an inventory local seamounts, analyzing the seasonal abundance of pelagic species an inter-annual time scale at a single seamount using underwater visual census, ultrasonic telemetry and fisheries observation, and assessing the fishermen and fisheries that depend on seamount ecosystems. We arrive at an inclusive definition of seamounts and consider a seamount to be any submarine peak or ridge abruptly rising from a level sea floor. The abrupt topographic nature of these features lead to its ecological significance, as a site attracting a diversity of fishes in relatively high abundance. We describe and encourage science-based management of seamount fish assemblages and present four major areas we believe will need further study if we are to understand and better manage seamount ecosystems and their related fisheries, including causation of productivity surrounding seamounts, scales of oceanographic processes impacting seamounts, connectivity of species to seamounts and the socio-economic impact of ecosystem management on fishermen