#cods

Atlantic Cod (Gadus morhua)

Family: Cod Family (Gadidae)

IUCN Conservation Status: Vulnerable

Native to the northern Atlantic Ocean, Atlantic Cods live in large shoals that may contain more than 10 million individuals, with larger, stronger individuals swimming ahead of their smaller travelling companions to determine the direction the shoal swims in and “scout” for predators such as Greenland Sharks and Orcas. Growing to be 68-130cm (27-51 inches) in length, adult Atlantic Cod are safe from all but the largest predators (particularly while in shoals) and may live for over 20 years. The diets of individuals of this species vary considerably depending on their size and maturity: large individuals (such as those that act as scouts) feed on moderately sized fish such as Atlantic Haddocks, Common Soles, Atlantic Mackerel and (on rare occasions) juveniles of their own species, while smaller individuals feed on smaller fish and marine invertebrates such as squids, bivalves, starfishes and sea cucumbers - regardless of size, food is mainly found using the single goatee-like barbel (a sensory organ that detects chemicals released into the water by prey) which protrudes from the front of the lower jaw. Many populations of Atlantic Cod are migratory and return to specific spawning grounds to reproduce each year; after arriving at a spawning ground, numerous males will circle around mature females while producing drum-like booming noises and fighting off smaller rivals in an attempt to impress the female, and upon successful courtship a female will produce clusters of several million tiny gelatinous eggs which will be fertilized externally by a male of her choice before being carried away to coastal environments by the tide. Most of these eggs will be eaten or otherwise die before they are able to hatch, but those that survive will hatch into tiny plankton-eating larvae which slowly grow into coast-dwelling juveniles before reaching maturity at around 2-4 years of age and travelling further from the coastline in search of a shoal to join. Atlantic Cods are regularly caught and eaten by humans, and while this has led to extremely concerning declines in the species’ population there is a potential for increased legal protection of wild Atlantic Cod (particularly those found at their spawning sites) and a higher reliance on farmed individuals for food (thus reducing the impact on wild populations) to give this species a chance to recover.

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Animal Advent Calendar - Day 19

Unknown fisherman gutting a few cods.