As a consequence, they are notably unproductive, highly vulnerable to overfishing and potentially have little resilience to overexploitation. The lead author just completed a senior NRC Associateship at PFEL and the second author is PFEL staff. The purpose was to examine how deepwater fisheries impact marine ecosystems. Since 1960, deepwater fisheries have contributed 600,000 - 1,000,000 MT annually to global marine fish landings. The accumulated biomass of previously unfished deepwater stocks are typically fished down, often within 5-10 years, to the point of commercial extinction or very low sustainable levels.
Most deepwater fisheries are today overfished or in danger of depletion.
The paper describes the risks associated with these deep water fisheries. In general, the risks to population viability of reduced stock size and age structure, the potential for species replacement, and the impacts on prey and predator populations are not known. However, deepwater trawl fisheries have been shown to have potentially severe impacts on the benthic fauna of seamounts, where deepwater fishes aggregate. This fauna, dominated by suspension feeders, such as corals, is typically restricted to the seamount environment and is characterized by high levels of endemism, which suggests limited reproductive dispersal. The ability of the benthic community to recover, following its removal by trawling, is not known.