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uncharismatic-fauna · 5 days

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At Last, the Atlantic Blue Crab!

A common sight on dinner tables in Canada, America, and Mexico, the blue crab-- also known as the Atlantic blue crab or the Maryland Blue crab (Callinectes sapidus)-- is native to the the Gulf of Mexico and the Atlantic coast of North America. This species is a bottom dweller, and can occupy a range of habitats from freshwater tributaries to the open bays and gulfs of the ocean itself. At times it may be found at high tide, but most individuals remain submerged at depths up to 36 m (120 ft) deep.

As indicated by its name, the claws and front body of male blue crabs are bright blue. Females are carry a blue tinge, but are largely brown or olive, though the tips of their claws are bright red. Otherwise, the two sexes may be distinguished by the shape of their underside, or "apron"; males have an inverted 'T' shape, while females have a wider, rounder shape. Individuals of both sexes may grow up to 23 cm (9 in) in width, and weigh up to 136 g (0.3 lbs).

Spawning for C. sapidus can occur year-round, but for most populations it peaks in October or November. When females are ready, they travel up estuaries and rivers to where populations of males are more concentrated, and then release pheromones in their urine to attract mates. Male crabs then compete for access, and guard their chosen mates fiercely for up to a week. During this time, the female molts, at which point the male fertilizes her. Afterwards, she may retain her mate's sperm for up to a year, during which time she returns to saltier waters. A female can fertilize 2 million eggs at a time, and will carry them in a mass under her abdomen until they hatch, about a week after fertilization. She may do this as many as 4 times throughout a single mating season.

Once hatched, Atlantic blue crab larvae are released into the ocean. Each larvae spends 30-40 days going through seven larval stages known as zoea; these stages are similar to the instars of a larval insect. However, zoea have hard shells and must molt at each stage of development. After the initial zoea stages, juvenile C. sapidus enter the megalops stage, which lasts 6-20 days. During this time juveniles move from the ocean into the estuaries in which they spawned. Finally, they molt into their final form, which resembles an adult-- albeit much smaller. Both males and females continue to molt throughout the year until they reach their full size. In total, both sexes go through about 25 molts each throughout their lives, which spans about 3 years in the wild.

Blue crabs have a wide and varied diet, as they are omnivores. In their larval stages, Maryland blue crabs consume primarily plankton and detritus. Megalops and adults will feed on clams, mussels, and oysters, small fish, kelp, seaweed, carrion, smaller blue crabs, and animal waste. In turn, both juveniles and adults are food for eels, large fish some sharks, stingrays, and humans. In fact, predation upon larval and sub-adult blue crabs is so heavy that, of 8 million eggs released by the mother, only 1 or 2 typically survive to adulthood.

Conservation status: The Maryland blue crab has not been evaluated by the IUCN. However, in recent decades, fisheries have noticed a severe decline in abundance, likely due to over-harvesting and pollution.

If you send me proof that you’ve made a donation to UNRWA or another fund benefiting Palestinians– including esim donations and verified gofundmes– I’ll make art of any animal of your choosing.

Photos

Kim Cover

Lynn Strauss

Jo O'Keefe

#atlantic blue crab #Decapoda #Portunidae #swimming crabs #crabs #decapods #crustaceans #arthropods #marine fauna #marine arthropods #coasts #coastal arthropods #atlantic ocean

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rattyexplores · 3 months

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Photos 1-2 - Carapace, washed up 10-15m away from body

Photos 3-4 - the rest of the body

Photos 5-6 - closeups of claws

Photo 7 - flattened hind leg / Photo 8 - the other legs

Photo 9 - closeup of carapace / Photo 10 - internal structure beneath carapace

Dead crab that washed ashore. The carapace had detached from the rest of the body and washed up separately, but its still a clear match in my eyes.

You can see how its last legs are modified (or flattened I guess) for swimming.

17/09/23 - Portunus sp.

QLD:WET - Cardwell, ocean shore

#Arthropods #invertebrates #invertblr #arthropod #arthropoda #Portunus #unidentified #Portunidae #Swimming Crabs #Decapoda #Decapods #crabs #dead tw #Crustacea #Crustaceans

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ametat-arts · 4 months

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comm for wavycookie

had an absolute blast on this, I love kelp forests :D

#kelp forest #underwater #ocean #swimming #anthro #moray eel #orca #dragon #fish #crab #shrimp

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daily-crabbys · 9 months

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Today's crab is: oh so vibrant

#daily-crabbys #crab #swimming crab #rainbow swimming crab

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cozylittleartblog · 1 year

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swatchvember: "beach episode"

an appropriate use of swatch's powers: drastically renovating the cafe every other month For Funsies! just shove a whole entire normal beach in there. why not. wear the worst outfit of your life. why not

they can't swim

#deltarune #swatchvember #swatch #swatchlings #kris #susie #queen #i mean ok they can swim but its very hard when you're Feathered and Still Clothed and got Thrown In Unexpectedly QUEEN #art #this is one of those concepts ive had sitting in my brain waiting to be microwaved and now i can microwave it #its always fun getting to look at their powers more the ability to draw things into existence is so op and they use it for the SILLIEST stu #stuff. this is probably the most extensive retheme they've done this is a completely different location #also they only drew one crab. they meant to draw more. they forgot. there is literally just One Crab #thats him there in the last one :) one crab #[falls in through the ceiling a day late] BTW MY SWATCH USES THEY/THEM PRONOUNS ONLY #january edit - the fact that i used my main blog queen tag and not the regular queen tag lmfao

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1o1percentmilk · 1 month

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