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Demersal FishGeoffrey SmithCHAPTER7IntroductionThe high rates of productivity within the Northwest Atlantic region provide an abundant food source for planktivores inthe water column, while still allowing significant energy to reach the ocean floor to support benthic communities. As aresult, demersal fish species, i.e., fish that live on or near the seafloor, are able to thrive on the abundance of available preyitems. These demersal species (which include Atlantic cod, haddock, flounders, monkfish, sea bass, skates, tilefish, andseveral estuarine-dependent species) are characterized by their close association with the seafloor for critical life stagesincluding feeding, juvenile nursery areas, and spawning. Historically, demersal fish in the region played a critical role as adominant predator, heavily influencing lower trophic levels in the system (Steneck 1997).The list of demersal fish species included in this assessment is comprised of teleosts (ray-finned fishes) and elasmobranchs(cartilaginous fishes) that utilize a variety of benthic habitats to complete various phases of their life histories.While the species within the group share the common attribute of close association with sea floor habitats, individualspecies utilize a variety of different habitats throughout the region. Atlantic cod and haddock demonstrate an affinity formore complex substrates including gravel, pebbles, and cobbles, while flounders and skates show a preference for finergrainedsubstrates such as sands and mud. In addition, many species within the group make distinct seasonal migrations,occupying shallower habitats in the spring and summer months, then moving offshore to deeper water habitats in thewinter in response to changes in water temperature.Demersal fish have also played a critical economic and cultural role in the region for centuries. Fisheries for cod, haddock,hake, and halibut are believed to be largely responsible for European settlement in North America some 500 years ago(Kurlansky 1997). Since then, demersal fish populations have helped support fishing communities up and down the eastcoast, providing a source of income, food, and community identity. Even today, demersal fisheries are important to theeconomies in many parts of the region despite significant declines in many commercially exploited demersal fishes.Technical Team MembersChris Bruce, The Nature Conservancy, VirginiaDan Coker, The Nature Conservancy, MaineMark Gibson, Rhode Island Department of Fish and WildlifeDavid Goethel, Commercial Fisherman and NEFMC Member, New HampshireRyan Gordon, The Nature Conservancy, MaineKohl Kanwit, Maine Department of Marine ResourcesJeremy King, Massachusetts Division of Marine FisheriesJack Musick, Ph.D, Virginia Institute of Marine SciencesTom Nies, New England Fisheries Management CouncilJay Odell, The Nature Conservancy, VirginiaPaul Rago, Ph.D., Northeast Fisheries Science CenterGeoffrey Smith, The Nature Conservancy, MaineDavid Stevenson, National Marine Fisheries ServiceNorthwest Atlantic Marine Ecoregional Assessment • Phase 1 Report 7-