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Atlantic Tomcod (Microgadus tomcod)

A collection of links and pages related to the Atlantic Tomcod and related recovery efforts.

Atlantic Tomcod Overview

Microgadus tomcodIllustration of an Atlantic tomcod (Microgadus tomcod).


Atlantic tomcod feed on small crustaceans, polychaetes, mollusks, and fish. From November through February, they spawn in shallow estuarine waters north of the Hudson River. A female can produce 6,000 to 30,000 eggs per year. When the eggs are released, they sink to the benthos and stick to whatever substrate they land on and incubate for a month. Twenty-four hours after hatching, larvae become photopositive and swim to the surface of the water to gulp air to fill their swim bladder. The larvae then move to the benthos and stay there feeding on zooplankton and polychaetes until they are big enough to travel the water column.


Atlantic tomcod are distributed along the coast from south Labrador to Virginia. They prefer the brackish waters of salt marshes and river mouths, but can also be found in freshwater. They are usually not found in depths exceeding 6 meters.

    History of the Fishery

    In the 1800’s, Atlantic tomcod were commercially important. They were harvested heavily in the Boston area, and were called “London trout.” 1n the 1950’s their numbers started to decline and the fishery was closed. Now they are caught as a winter sport fish.

    Current Status and Management

    Currently, Atlantic tomcod are listed as Least Concern. Their population is presumed to be large and relatively stable with no major threats. It is uncertain how big the population actually is.

    Links, Useful documents

    Prepared by:
    Meg Begley
    University of Maine
    American Fisheries Society Student Subunit 

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