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Atlantic Blue Crab

Callinectes sapidus


This is a species of crab native to the waters of the western Atlantic Ocean and the Gulf of Mexico. Males and females of C. sapidus can be distinguished by the sexual dimorphism in the shape of the abdomen (known as the "apron"). It is long and slender in males, but wide and rounded in mature females.


Callinectes sapidus is native to the western edge of the Atlantic Ocean from Nova Scotia to Argentina and around the entire coast of the Gulf of Mexico.


The natural predators of C. sapidus include eels, drum, striped bass, spot, trout, some sharks, humans, and cownose sting rays. C. sapidus is an omnivore, eating both plants and animals. C. sapidus typically consumes thin-shelled bivalves, annelids, small fish, plants and nearly any other item it can find, including carrion, other C. sapidus individuals, and animal waste. C. sapidus may be able to control populations of the invasive green crab, Carcinus maenas; numbers of the two species are negatively correlated, and C. maenas is not found in the Chesapeake Bay, where C. sapidus is most frequent.

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Thanks Luis!

@Scott thank you for letting me know that and for moving my photo :)

@alice thank you.

alicelongmartin 6 years ago


Scott Frazier
Scott Frazier 6 years ago

Nice image. I moved your crab to the Arthropod category for you. :-)
Just a tip: the habitat box is for information on the habitat of "your spotting". General information including habitat is widely available and you can provide the source of such information to other users by inserting a reference link (e.g. from Wikipedia or Encyclopedia of Life) in one of the spaces provided. However information on your spotting is unique and can only be provided by you! It supplies accessory information on your unique "data point". Here is what Project Noah say about this type of information: "Habitat: Please state the actual habitat where you photographed the spotting - this information can then be used to track changes in habitat, such as those caused by human intervention or habitat destruction. Again, it is not necessary to state published habitat information here, this can be referenced in the 'reference links' box." ( Look for "What do I put in the fields?). Thanks!

LuisStevens 6 years ago

Good find!

Trinidad and Tobago

Spotted on Jan 1, 2014
Submitted on Jan 1, 2014

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