urchin attacking!!

[bronco300]

well....the free rock boring urchin i just recived attached himself to my xenia my fiance said he was there all day...........i dont know if he was eating it or not.....but when i moved the shell the xenia stalk was attached to, the xenia came off and was attached to the urchin. the xenia does have a spot on him now...dont know if its from a spike, or from the mouth eating...but i was told by the guy who gave it to me that he is completely safe....should i sell him back to an lfs? how much would one go for?thanks...help my poor corals
Luke P

 

[nanocuber7]

from what i understand urchins attach things to themselves like decorator crabs. this help them camoflouge better. they use a glue like substance to attach things to them and your urchin probably just attach your xenias to him. i dont think the xenias will harmed unless your urchin never is out during the day. as long as they get light i think they'll be fine.

 

[debbie]

What type of urchin is it?
I have a purple urchin whom motors around all over my mushrooms. I have never seen any damage done to them but then again I can only speak for the one I have.
One thing urchins love to do is decorate themselves with loose corals, shells etc. Right now mine is moving around with two empty snail shells on top of its self. They can get quite creative at their decorations.
Hope there is more replies out there to help you. But if you can post what type of urchin it is that should help some.
Deb

 

[bronco300]

its a rock boring urchin from what i have been told

 

[ophiura]

Some urchins will have a taste for soft corals, including Xenia. I wouldn't say any are completely safe. If you have observed this behavior, I would remove it. While they will pick up unattached things like rocks, frags, etc...I do not believe that the behavior you describe is related to that. And even if it was, I don't think you would find it desirable.

 

[bronco300]

thanks ophiura...nowmy concern is the urchin, since i took the xenia off...he hasnt moved and inch, and he is out in the open....i'll giv himsome time...but still worries me

 

[snailheave]

how do urchins reproduce?
i used to have only one urchin who came with a piece of live rock, now there are 4. they might have been hiding in the beginning, but i really didn't see 4 :notsure:

 

[sprang]

Get him outta there! If he's not eating your coral yet he will eventually. If you have lunars watch him at night and you will see.

 

[ophiura]

Originally Posted by snailheave
how do urchins reproduce?
i used to have only one urchin who came with a piece of live rock, now there are 4. they might have been hiding in the beginning, but i really didn't see 4 :notsure:

They are broadcast spawners and there are usually separate sexes, meaning you need to be lucky enough to get at least two, and they need to be of breeding size.. While I suppose it is possible, I suspect all of yours were tiny hitch hikers. The larvae of urchins are extremely delicate, and while they are commonly used in research, I don't think they would survive long term with pumps and skimmers.

 

[snailheave]

mine are small, the largest is no bigger than a ping pong

 

[bronco300]

do urchins ever "play" dead?? he hasnt moved yet from his spot, but every now and then i see a spike or two move some....so it seems he is alive, still waiting for him to jump up and move

 

[debbie]

When I spot feed mine it will be in the same place the following day. So if they are eating something I think that is when they are the most still, otherwise mine motors around all over constantly.
Deb

 

[bronco300]

ok, well i dont know what to do with him...he has lost one needle, dont know if its usual, but it is stuck in a rock, and he lost it....but when i flip him over, a rock is stuck to his mouth....and then one or two needles will move some, dont know if its him moving them or gavity etc....but i wish he would make up his mind. lol.

 

[bronco300]

anyone?

 

[debbie]

This all sounds normal to me. Mine will be in one area for quite sometime. When you say it is attached to the rock that is a good sign that it is still alive. They sometimes do shed needles but when you see alot of them everyday then it spells trouble.
I would just leave it alone if you want to keep it and just watch what it does. Obviously it has taken an interest in your xenia. Mine has never bothered any of my mushrooms and I see it all the time move over them.
Can you post a picture here so we can see what it looks like?
Deb

 

[bronco300]

this is him a day or two ago....he doesnt look quite like that anymore, not so many spikes up....i'll get a better pic tomorrow.

 

[debbie]

Wow, that is quite the dude you have there. I don't know much about them at all. Mine is the purple one pictured below here.
Deb

 

[bronco300]

yea, i think the little guy is awesome, but i just cant decide if he is dead, dying, or alive....i just wish id know so i could tell what to do with him. lol i dont want to toss the poor little guy if he is alive....here is a recent pic taken 1 min ago

 

[ophiura]

Admittedly, it isn't looking great. But unless this was a really small tank I wouldn't worry to much. Keep an eye on water quality and such, but even if it were dying the other critters would take care of it.
You should see spines moving but they often do become more ridged if you pick them up and stop moving.

 

[bronco300]

it is 10 gallons, i'll keep an eye on him...every now and then you can see his spike move a tiny bit...especially if he gets touched....but who knows, i'll keep a close eye