40 Fun Facts About Blue Crab

When a blue crab is cooked and its blue pigment breaks down, which colour does the shell turn?

Orange-red is the colour of astaxanthin, a pigment that survives the heat. In a live crab it is masked by a blue pigment that cooking destroys.

Chesapeake crabbers say the narrow apron under a male blue crab looks like which landmark?

The Washington Monument is the local shorthand for a male's slender apron. A mature female's rounded apron is compared to the dome of the US Capitol.

Which Chesapeake Bay state made the blue crab its official state crustacean?

Maryland gave the blue crab the title in 1989. The crab is the state's most valuable commercial fishery and the heart of its crab cakes and summer crab feasts.

Which grim habit forces a freshly molted blue crab to hide until its shell hardens?

Cannibalism is routine for blue crabs, which eat almost anything they can find, including smaller and soft-shelled crabs of their own species.

Which Baltimore spice blend, created in 1939, is chiefly used to season blue crabs and shrimp?

Old Bay is named after the Old Bay Line, a steamship company that sailed out of Baltimore. Its creator, Gustav Brunn, was a spice merchant who had fled Nazi Germany.

The second half of the blue crab's scientific name, sapidus, is a Latin word meaning what?

Savory is what sapidus means, a compliment to the crab's sweet meat. Zoologist Mary Rathbun gave the species its name in 1896.

After mating just once in her life, a female blue crab stores what for up to a year?

Sperm kept from that single mating lets her fertilise several batches of eggs months later, after she has migrated to saltier water.

How do blue crabs in Chesapeake Bay spend the winter once the water turns cold?

Buried in bottom mud, the crabs rest until spring. Scientists use the lull to count them, sampling the bay bottom in a yearly winter dredge survey.

Blue crabs can see in almost every direction at once thanks to which feature?

Stalked compound eyes give the crab a near all-round view. They also see in colour: studies show blue crabs use colour vision when choosing a mate.

Besides her broader apron, which feature marks out a mature female blue crab from a male?

Red-tipped claws set her apart from a male, whose claws are bright blue. Courtship studies found that males prefer females showing red on their claws.

Which Gulf state's blue crab fishery was the world's first to be certified as sustainable, in 2012?

Louisiana won the Marine Stewardship Council's label in 2012, and must pass yearly monitoring to keep it. The state lands over half of all blue crab caught in the Gulf of Mexico.

Which European country named a 'commissioner for the blue crab' as the invader ate its clams?

Italy created the post as blue crabs spread through the Po delta and along the Adriatic coast. Local authorities and fishermen there are working together to try to eradicate it.

How did blue crabs from the Americas most likely reach European and Japanese waters?

In ships' ballast water is how the species is thought to have travelled. Europe's first was recorded at Rochefort, France, around 1900, and it now lives as far east as the Black Sea.

Which endangered bird leans heavily on blue crabs for food while wintering on the Texas coast?

The whooping crane winters at Aransas National Wildlife Refuge, where blue crabs have supplied up to 90 percent of its energy intake in some winters.

Which bait do recreational crabbers traditionally tie to a string to lure blue crabs to a dip net?

Chicken necks, or sometimes a fish head, go on the string. When a crab tugs, the line is eased in slowly so a net can scoop the crab up before it lets go.

What name is given to the rare event when low-oxygen water drives blue crabs to crawl onto land?

A jubilee, or crab jubilee, is a warning sign rather than a party: the crabs are fleeing water so short of oxygen that staying would suffocate them.

What do crabbers call the mass of eggs that a female blue crab carries under her apron?

A sponge darkens as the larvae inside use up their yolk. After about two weeks the female releases them near the mouth of the estuary.

Roughly how many eggs can a single female blue crab carry in one brood?

About 2 million eggs can ride in a single brood, yet almost none make it: by one estimate only one egg in a million survives to become an adult.

What becomes of the missing limb when a blue crab loses a claw or leg in a fight?

It regrows as it molts, though not at once: a replacement claw or leg takes two or more sheddings of the shell to appear.

Chesapeake crabbers have which nickname for an adult male blue crab, especially a big one?

Jimmy is the name for a male, while a mature female is a sook. The biggest jimmies tend to come from rivers such as the Wye and the Chester.

Which fortified wine is traditionally added to she-crab soup, a rich blue crab bisque, at serving?

Sherry goes in as the soup is plated, a small dry splash over a bisque enriched with cream and crab roe. The dish is a speciality of the South Carolina Lowcountry.

What nickname do Atlantic coast seafood lovers give the yellowish organ inside a blue crab's body?

The mustard is the crab's hepatopancreas, named for its colour. When a soft-shell crab is cleaned, fans ask the vendor to leave it in.

A traditional Chesapeake crab cake is built around which prized grade of blue crab meat?

Jumbo lump goes in with only a very small amount of binder. The cakes are chilled before cooking so that they hold together without extra filler.

Which William W. Warner book about blue crabs and their catchers won a 1977 Pulitzer Prize?

Beautiful Swimmers takes its title from the crab's genus name, Callinectes, which is Greek for exactly that. The book stayed in print for the rest of its author's life.

What traditional name is used for the people who harvest blue crabs and oysters on Chesapeake Bay?

Watermen work the bay all year, crabbing and oystering from V-hulled workboats. In England the same word once meant the boatmen who ferried passengers on the Thames.

Which turtle often drowns in blue crab pots, leading crabbers to fit excluder devices?

The diamondback terrapin shares the crab's coastal range, and small ones slip through a pot's flexible funnels. Excluder devices keep them out without reducing the crab catch.

Which Chesapeake Bay seagrass, prone to die-offs in hot summers, is essential habitat for juvenile blue crabs?

Eelgrass beds shelter young crabs, and females need them for their final molt. In 2005, high temperatures caused a massive die-off of the plant in Chesapeake Bay.

By eating which grass-grazing marsh snail do blue crabs help protect salt marshes from damage?

Periwinkle snails feed on marsh grasses, so scientists worry that a drop in blue crab numbers would leave more snails grazing and less marsh standing.

Female blue crabs nearing their final molt attract a mate by releasing a pheromone in which fluid?

Urine carries the chemical signal, and males compete to answer it. The winner guards the female until she molts and mating can begin.

Why were abundant blue crabs once considered a nuisance by fishermen in the lower Chesapeake Bay?

They clogged fishing nets so often that seine crews treated them as pests. The same crab is now the most valuable commercial fishery in the bay.

Before the crab pot, which baited gear was the first major commercial way to catch blue crabs?

The trotline is a long line anchored at both ends, with baits tied on every few feet. Commercial crews still work it on the tributaries of Chesapeake Bay.

Crab pots exploit which escape instinct of confined blue crabs to move them into a second chamber?

Swimming upward is how a trapped crab tries to flee, so the pot has a chamber above the bait well where its chances of escape are much smaller.

Which shape are the tips of a blue crab's rearmost pair of legs, letting it swim as well as walk?

Flat paddles at the rear scull the crab along, usually turning 20 to 40 times a minute and blurring when it darts away.

Blue crabs belong to the crustacean order Decapoda, a Greek name that points to which feature?

Ten legs is the meaning, from the Greek words for ten and foot. On a blue crab the front pair are not for walking at all: they carry the claws.

Which invasive species do abundant blue crabs appear to keep out of Chesapeake Bay?

The green crab, a European invader, grows scarce wherever blue crabs are plentiful, and it is absent from the bay where they are most abundant.

What do crabbers call a male blue crab cradling a female beneath him in the days before they mate?

A doubler is really a pair: the male carries the female for a few days, mates once she sheds, then stays until her new shell hardens.

What name do biologists give the tiny drifting larva that hatches from a blue crab egg?

Zoea drift in coastal ocean water for weeks, molting several times, before changing into a second larval form that settles back in the estuary.

Which Eastern Shore town stages blue crab races at the National Hard Crab Derby each Labor Day?

Crisfield has held the derby since 1947, with crab races, a parade and contests for picking and cooking crab. The town bills itself as the Seafood Capital of the World.

Zoologist Mary Rathbun, who first described the blue crab species in 1896, spent her career where?

The Smithsonian was her workplace from 1884 until her death in 1943. In that time she described more than a thousand new species and subspecies.

Where does an experienced crabber grab a live blue crab to stay clear of its claws?

The base of a back leg, one of the pair the crab swims with, is the safe handhold, reached from behind. If a crab does clamp on, letting it hang often makes it drop off.