Report Shows Importance of Shallow-Water Habitat

Report Shows Importance of Shallow-Water Habitat

A new report by NOAA Fisheries documents the importance of shallow-water marine and estuarine habitats in the Gulf of Maine. The report summarizes what is known about the “functional value” (for survival, growth to maturity, and reproduction) of 8 different types of habitat for 16 fish and invertebrate species.

Habitat use was assessed for the various life stages of each species in the following benthic (bottom) habitats: mud, sand, gravel/cobble, boulder, eelgrass, macroalgae, salt marsh channels, and shell beds.

Habitat use scores (1 = present, 2 = common) were assigned to each benthic life stage known to occur in depths less than 10 meters and then summarized for all species in each habitat type. The evaluation was based on a review of approximately 125 publications in scientific journals. In cases where information was lacking, scores were based on best professional judgment.

The results show that shallow-water habitats in the Gulf of Maine provide valuable ecological benefits for a variety of commercially and recreationally important species. The top ranking habitats—those where species were either “common” or “present,” were: 1) sand and gravel/cobble; 2) mud, eelgrass and macroalgae; 3) boulders and salt marsh channels; and 4) shell (mussel) beds. However, for species and life stages that were considered to be common, vegetated (eelgrass and macroalgae growing on rocky substrates), sand, and gravel habitats ranked higher than the other 4 types.

Some species, like cod and lobsters, move into deeper water as they get older, while others like mussels, clams, windowpane and smooth flounders, and cunner are restricted to shallow water for their entire lives. Species like winter flounder, smooth flounder, sand lance, clams, cunner, mussels, and clams spawn in shallow water.

Read the full PDF report from NOAA Fisheries.