Crabs hiding their claws

Fish & Invertebrate sightings and descriptions, hosted by resident NWDC ID expert Janna Nichols (nwscubamom).
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YellowEye
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Crabs hiding their claws

Post by YellowEye »

Hi
I noticed that with several species of crab, as soon as they see me coming with my camera, or fire my first shot, they'll hide or tuck in their claws. A crab shot w.o claws doesn't make for as good of a crab photo for sure!

Anybody know what's going on? Do crabs just like hiding their claws because crab claws make a tasty treat for predators? or am I just imagining things? is their anything I can do? I tried waiting one crab out, but he wore out my patience!

Thanks!
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Greg Jensen
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Re: Crabs hiding their claws

Post by Greg Jensen »

Pretty hard to get inside their head and know why they do some of the things they do- I've always figured they're just clamping themselves tighter to the substrate to be less conspicuous and/or harder for a predator to pull off.
What species was it? I know Scyra (sharpnose crabs) often do that.
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YellowEye
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Re: Crabs hiding their claws

Post by YellowEye »

Hi Greg
I think sharpnose crab was one of them. Even hermits, like even the one in your profile pic is tucking in his claws, where they sometimes have them out before you approach. Thanks!
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Dusty2
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Re: Crabs hiding their claws

Post by Dusty2 »

I'm just guessing here but I think it is a defensive behavior. If you were crab sized He would raise his claws to show aggression and make himself look bigger but since you are one hell of a big fish the natural instinct would be to make himself as small and inconspicuous as possible. Like with the little red octo's. It's what I call rock mode. Hide all your appendages and look as much like a rock as you can. Whether or not you have thought about it that camera rig with it's long arms looks a whole lot like a huge monster crab from the crabs point of view.
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YellowEye
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Re: Crabs hiding their claws

Post by YellowEye »

Dusty2 wrote:Whether or not you have thought about it that camera rig with it's long arms looks a whole lot like a huge monster crab from the crabs point of view.
Hahaha, that's funny :rofl:
Thanks Rich!
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RoxnDox
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Re: Crabs hiding their claws

Post by RoxnDox »

YellowEye wrote:
Dusty2 wrote:Whether or not you have thought about it that camera rig with it's long arms looks a whole lot like a huge monster crab from the crabs point of view.
Hahaha, that's funny :rofl:
Thanks Rich!
so now we go from a DeathStar camera rig to "Crabzilla"... :supz:

Jim
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ljjames
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Re: Crabs hiding their claws

Post by ljjames »

I would think they are just protecting their pincers from the giant unknown thing swimming overhead that might like to eat delicious crabby looking things. Claws are good for defense and food gathering. If I were a crab and wanted to not get eaten, I'd do my best to blend in and look more like a rock than a crab, and rocks don't have claws ;) The only crab I know that doesn't hide its claws on a regular basis is the Kelp crab, and I think that's probably its just the aggro beast mode of the crab world that simply gives zero F***'s ;) (also it usually lives up 'on' things so its higher in the water column and possibly less threatened by us swimming by) but this is pure speculation ;)
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nwscubamom
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Re: Crabs hiding their claws

Post by nwscubamom »

Dusty2 wrote:I'm just guessing here but I think it is a defensive behavior. If you were crab sized He would raise his claws to show aggression and make himself look bigger but since you are one hell of a big fish the natural instinct would be to make himself as small and inconspicuous as possible.
Hmmm, I've seen the exact OPPOSITE of this! These teeny little crabs see me coming and put up their dukes and wave their teeny little crabby arms and crabby claws around at me, ready for a fight.

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ljjames
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Re: Crabs hiding their claws

Post by ljjames »

They probably know their claws are not tasty... or perhaps they are simply aggro due to eternally compensating for their diminutive size... "you wanna piece o'me!??!'
nwscubamom wrote:
Hmmm, I've seen the exact OPPOSITE of this! These teeny little crabs see me coming and put up their dukes and wave their teeny little crabby arms and crabby claws around at me, ready for a fight.

- Janna
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