Crab on Acropora

stubbsz

stubbsz

New member
So as I dipped my Acropora that I picked up from Hayward after the swap using my raffle winnings and I noticed that I had a little crab on deep in the arms of the coral. I was dipping and inspecting for bugs otherwise I would never have noticed. I've left him on the coral for now and he's moving around as though he's been there a while.

Are these crabs symbiotic with the coral or is he going to do some damage. I can't find any damage on the coral at the moment.

I'd take a picture but I can't get a shot of the little git.

-Adrian
 
It could be an acro crab, symbiotic crab which rids the acro of pests and I think the acro feeds it with slime or something...
 
You went to the LFS in hayward? I went there after the last meeting and picked up an acro with my multiple gift cards (which btw most of which STN'd out.. *grumble*), it had not one but TWO of these. They were quite hairy too, little black pinchers, of course I removed them, put them in the sump of my softie tank and left a message on RDO, since if I posted in the SPS forum here first thing people would scream is "GORILLA CRAB KILL IT" or something equally stupid.

But there was voice of reason and mentioned they fed off the coral mucus or something... either way don't know if I believe them, and left them in the sump.

So does the crab look like this?
crabor8.jpg
 
I'm no expert (not even going to pretend), but I read that "hairy" crabs are usually bad in acros while smooth "porcelain" crabs are often not.
 
Hard to tell can't get a look at him but he's a little hairy, not a porcelain crab. No where near as meaty as that bad boy in the photo, claws don't look as menacing.
 
i read another article (can't find where) that studied them in the wild. THey found that when coral colonies had the crabs the coral was over all more healthy then those without them. something to do with how they also clean the acro's from ditritus. so i would keep them. but thats just me.
 
Hey Adrian,

My friend and I were there with you at the LFS while you waited patiently for service. ;) I saw that little crab on the acro you picked up while it was in the prop tank. It definitely looked like an acropora crab with those little white claws and perched neatly in the stalk. I am not an expert in these types of crabs, but my understanding is that they are good for the coral in the way LordHelmet mentioned.

That being said, I look at it this way: Either its there to eat the coral, or live in it. Do you really want to take the chance?
 
Hi Mike.

Did I really seem patient? :)

I saw a completely different crab that you or your friend pointed out that was on a different acro. But as you say the one on mine just kind of perches there and barely moves. The coral looks nicer in my tank and I'm really glad I fought the coral raiding couple off. I swear that every time someone pointed at a coral they liked, the wife would add it to the 50 odd she'd already snagged.


-Adrian
 
Your wife takes you to the cleaners at the LFS too, huh ? Glad to know I am not alone :D

About the crab, the one Mike posted a pict of I only have to say "GORILLA CRAB, KILL IT !!!" :D

But seriously, as far as acro crabs go :

smooth shell == good
hairy shell and/or blue eyes == bad

We had a couple of hitchiker crabs in an acro we picked up from an LFS down there and I personally witnessed it eating the acro flesh right off of the base of the branches. It suffered a quick, messy death (since we couldn't easily get it out of the coral and after seeing it ripping the flesh off of the acro I had little motivation to try to actually save it). And that crab looked alot like the one in Mike's picture.
 
Funny, after reading this thread, I found a little hairy crab in a birdsnest colony that I got recently. Decided not to take the chance and took it out - was a pain to snag, and I felt kinda bad about it!
 
<a href=showthread.php?s=&postid=9221265#post9221265 target=_blank>Originally posted</a> by Natterjak
Funny, after reading this thread, I found a little hairy crab in a birdsnest colony that I got recently. Decided not to take the chance and took it out - was a pain to snag, and I felt kinda bad about it!
Click to expand...

Any sign of damage. I see none on mine. Can't bring myself to evict him.
 
Kinda hard to say, as it's a light pink color already - but there did seem to be a couple small patches that looked a little lighter than the rest, so I didn't want to take any chances.
 
<a href=showthread.php?s=&postid=9221319#post9221319 target=_blank>Originally posted</a> by stubbsz
Any sign of damage. I see none on mine. Can't bring myself to evict him.
Click to expand...

Yeah I had had reservations removing the buggers too, although I didn't out right kill them, just stuck them in my softie tank sump (I still see them alive too so they're eatting :)), but I had way too much stuff in my tank to have to go crabbin' later if I saw damage. Funny thing is that stupid colony almost all STN'd away (luckily I didn't spend too much, mostly raffle prize gift cards)
 
Funny thing is that stupid colony almost all STN'd away (luckily I didn't spend too much, mostly raffle prize gift cards) [/B]
Click to expand...

You must have lowered the resistance of the coral by taking away its symbiotic buddy.
 
Just thought I'd bring this thread back to mention that I lost my nerve and banished the crab to the sump. Easy to catch him as he never moves more than an inch on the acro as far as I could tell.

The cool thing is that I but the acro back at a different angle and lo and behold I find another even smaller crab living on the other side. This one is smooth white with a lone-ranger mask over his eyes :) Pretty sure this is the safe crab just like the one in delsol650's link.

Gotta get a camera as I'd love to get a decent shot of this bad-boy.
-Adrian
 
You must log in or register to reply here.

Similar threads

C
Two Red Legged Hermit Crabs One Shell
Replies
3
Views
165
griss
griss
M
Leather coral pest or disease
Replies
5
Views
246
kfisc
kfisc
T Diddy
I’ve got a parasite problem
Replies
15
Views
678
griss
griss
A
New Naso Tang breathing heavy and not swimming much anymore
Replies
2
Views
255
griss
griss
H
25 year old yellow tang dying :(
Replies
10
Views
499
sallypur
S
Back
Top