Species · GBIF taxon 2415893
Atlantic Tomcod
Microgadus tomcodAlso known as Frostfish, Winter Cod
Atlantic tomcod are small, bottom-dwelling members of the cod family that thrive in icy coastal waters, estuaries, and rivers. They produce specialized antifreeze proteins in their blood, allowing them to remain active and spawn under solid ice during the dead of winter. These resilient fish serve as a vital ecological link, converting small invertebrates into food for larger marine predators.
Cold-waterBottom-dwellerEstuarine
Licensed referenceH.L. Todd 1884 / Public Domain · Public Domain
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & prey
- Amphipods
- Mysid Shrimp
- Polychaete Worms
Predators
- Striped Bass
- Bluefish
- Double-crested Cormorant
ThreatsWater pollution, habitat degradation, and warming winter water temperatures
HabitatsEstuaries, brackish bays, coastal waters, and freshwater rivers
Life span3 to 4 years
Size / weightNot available
Classification
- OrderGadiformes
- FamilyGadidae
- GenusMicrogadus
- SpeciesMicrogadus tomcod
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Winter Angling: Look for them in tidal rivers and estuaries during the coldest months when they migrate upstream to spawn.
- Identification: Distinguish them from young Atlantic cod by their elongated second pelvic fin ray, which acts as a feeler.
- Catch and Release: Handle gently with wet hands to protect their delicate slime coat if caught.
Image unavailableClose Relative 
Close Relative NOAA / Public Domain (NOAA) · Public Domain (NOAA)
Family Member J. Deeds FDA / Public Domain (FDA) · Public Domain (FDA)
Family Member Unknown / CC-BY · cc-by
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