Shallow water benthic habitats in the Gulf of Maine: A summary of habitat use by life stages of common marine and estuarine species
Shallow-water estuarine and coastal marine habitats in the Gulf of Maine comprise some of the most productive habitats in the northeastern United States and have been identified as Essential Fish Habitat (EFH)1 for many species of importance to commercial and recreational fisheries. However, these near-shore habitats are also the most vulnerable to human disturbances due to their proximity to coastal population centers. The purpose of this report is to describe the importance of shallow-water habitats (0-10 meters) for spawning, feeding, and growth to maturity for 16 fish and invertebrate species in the Gulf of Maine based on a literature review. The species include a mix of federally managed fishery species, state-managed fishery species and other species that are important members of the shallow-water marine ecosystem. Habitat use was assessed for individual life history stages of each species in eight shallow-water benthic habitats: mud, sand, gravel/cobble, boulder, eelgrass, macroalgae, salt marsh channels, and shellfish beds. Habitat use scores (0 = absent, 1 = present, and 2 = common or abundant) were assigned to each benthic life stage of each species known to occur in depths less than 10 meters. Scores were then summarized for all species in each habitat type. According to this evaluation, shallow-water habitats in the Gulf of Maine are used by young-of-the-year juveniles of all 16 species. Additionally, older juveniles of 12 species and adults of 11 species also rely on these habitats. Nine of the sixteen species spawn in one or more of these habitats. Further analysis shows that sand and gravel/cobble habitats are used by the most species and life stages, followed by mud, eelgrass, macroalgae, boulder, salt marsh channels, and shell (mussel) beds. Shallowwater habitats in the Gulf of Maine provide valuable ecological services for a variety of species. Mud, sand, gravel/cobble, and vegetated habitats are particularly important as juvenile nursery grounds for species such as Atlantic cod, Atlantic tomcod, American lobsters, winter flounder, soft-shell clams, and blue mussels.