Animal Update: Blue Crabs

Two blue crabs have been added to our Tidal Marsh exhibit!

Published November 22, 2017

Blue crabs can be found along the Atlantic coast, as far north as Nova Scotia and all the way to Argentina. Within the Chesapeake Bay, male crabs tend to prefer the fresher waters in Maryland and upper tributaries, while females prefer saltier waters.

blue-crab

Despite their name, blue crabs are typically gray to dull blue-green in color. Only their claws are truly blue, but females have bright orange-red coloration at the tips. Blue crabs generally walk sideways, clearing a path with sharp lateral spines. Their sharp claws are used for defense, digging and gathering food. 

They will feed on almost anything they can get their claws on, including mussels, snails, fish and plants—including dead fish and plants! They are also excellent swimmers, with specially adapted hind legs that are shaped like paddles.

Adult crabs can grow up to 4 inches long and 9 inches wide. They grow by molting or shedding their shells. Following the molt, the crab's new shell is pliable and easily stretched. In this condition, the crab is called a soft-shell crab. Due to the large amount of water the crab consumes during the molt, the soft shell begins to expand and increase in size. Within two hours, the new shell begins to harden.

Stay tuned for more behind-the-scenes updates!

 
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