The European green crab has a square carapace that usually measures up to 2.5 inches long and 3.5 wide.

This species has long legs and long, asymmetrical claws.

The coloring of the European green crab isn’t a defining characteristic since they can also appear red if they haven’t molted from environmental factors. Not only are the red-shelled versions more aggressive, but they have a harder time adapting to the more extreme temperatures and low salinity environments.

The simplest identifiers for this species of crab are the 5 teeth behind each eye as well as the three lobes between their eyes.

The European green crab goes by different names around the world such as the “shore crab” in the British Isles. They were first native to the north-east Atlantic Ocean and Baltic Sea, but were spread out to Africa, Australia, and North and South America on boats or in seaweed that was used to pack seafood. They can live in a variety of habitats from rock, mud, and sand with a variety of salinities and temperatures ranging from 32 to 86°F!

The European green crab is a unique predator that is able to adapt. They will explore their feeding area and learn where their prey often visits as well the best way to catch them. The European green crab eats a variety of mollusks but their preference of younger or softshell species has had negative impacts on many fisheries around the world. If predators are present during hunting time, these crabs can use different methods of camouflage depending on the environment they’re in.

The European green crab’s mating season is towards the end of summer. Female crabs will molt during this season and become very vulnerable, which is when a male counterpart comes to protect her in her time of need. A few months later, she will drop an egg sac which the male will fertilize. After successful fertilization, the female will carry the sac into deeper, safer water where up to 185,000 eggs will develop! After hatching, the larvae will travel to the surface for two weeks until they reach the megalopae stage where they are essentially miniature crabs with tails. In their final molt, they will lose the tails and become full adult European green crabs.

Due to their adaptability and diet, they are linked to the 1950 decline of the soft-shelled clamming industry in the US.