Atlantic cod mature at five years old. They spawn every year after that, though they will sometimes skip a year. When Atlantic cod first hatch, the fry eat zooplankton and small crustaceans. As they grow, the young fish eat shrimp and small lobsters. Adults eat mainly herring and capelin.
Seals are the main predator of Atlantic cod. Prior to , Atlantic cod were also a heavily fished species. Their meat is highly valued for eating because it has a mild taste and large flakes.
Historically, Atlantic cod was dried and salted. They, in turn, are eaten by larger carnivores such as tuna, halibut, shark, and squid. It is microscopic in nature.
Plankton are marine drifters — organisms carried along by tides and currents. Scientists classify plankton in several ways, including by size, type, and how long they spend drifting. But the most basic categories divide plankton into two groups: phytoplankton plants and zooplankton animals.
Assorted Plankton. Plankton are the unseen heroes of many ecosystems providing food to a wide variety of species from tiny bivalves to whales. Though they are microscopic in size, organisms called plankton play a big role in marine ecosystems. Atlantic cod spend most of their time on or near the seafloor but may be observed feeding higher up in the water column at times. They eat a variety of prey, including several species of bony fishes, American lobsters , and other invertebrates.
Adult Atlantic cod are only eaten by large sharks, but juveniles are eaten by a variety of medium-sized predators and are often even eaten by cannibalistic adults. Atlantic cod reproduce through a behavior known as broadcast spawning, where females release eggs and males release sperm into the water column above the seafloor, at the same time.
This method increases the likelihood that eggs will become successfully fertilized and that fertilized eggs will not be eaten by egg predators near the seafloor. Though they form large reproductive groups, researchers believe that dominant males gain exclusive or nearly exclusive rights to spawn with available females.
Cannibalism and year-class strength in Atlantic cod Gadus morhua in Arcto-boreal ecosystems Barents Sea, Iceland, and eastern Newfoundland. Dolgov, A. Cannibalism and its importance for formation of recruitment of Arcto-Norwegian cod in the Barents Sea. Neuenfeldt, S. Trophodynamic control on recruitment success in Baltic cod: the influence of cannibalism. Long-term changes in trophic patterns of Iceland cod and linkages to main prey stock sizes.
Uzars, D. Cod Gadus morhua L. Yaragina, N. Variability in cannibalism in the Northeast Arctic cod Gadus morhua during the period Marine Biology Research. Log in to comment.
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