sea urchin question

[nereef]

my girlfriend brought home a sea urchin from developemental bio lab today. i can't identify it. it has purple short spines. my tank is fowlr with crabs snails shrimp and one mushroom. eating coraline isn't a concern, but i don't want it to go crazy on my snail population or eat my mushroom.
should i add it?

 

[sepulatian]

Can you get a picture of it or look online to find out what kind it is?

 

[nereef]

it looks very similar to a rose pink urchin(Sphaerechinus sp.) we get at the lfs.

 

[ophiura]

This urchin is typically Arbacia punctulata. If not perhaps Lytechinus.
You'll need to know what temp they kept it in in the lab.
There is always a risk to coralline, but some have proposed urchin grazing can help spread it.

 

[nereef]

thanks ophiura. i just got an email back from the professor. this urchin is Lytechinus variegatus. i've got coraline everywhere and wouldn't mind getting rid of some of it. is there any concern with mushroom corals or slow moving inverts?

 

[nereef]

bump

 

[larryndana]

i think it will, maybe someone will say for sure.

 

[nereef]

well, the urchin entered my tank last night after a 6 hour drip acclimation. we'll just have to see what happens.

 

[reefkprz]

Originally Posted by NEreef
thanks ophiura. i just got an email back from the professor. this urchin is Lytechinus variegatus. i've got coraline everywhere and wouldn't mind getting rid of some of it. is there any concern with mushroom corals or slow moving inverts?
I've never seen a rose urchin eat mushrooms, we used to put them in our coral display at the pet store but ended up moving them because we were trying to get coraline growth in the display. As for them possibly helping it spread by grazing on it I had never thought of it, but in theory if the coraline doesnt all die while being eaten the resulting effluent the urchin poos out could "seed" the tank by moving particles from one location to another, this method of reproduction in plants isnt unheard of, birds spread plants all the time pooping out seeds. this is a very interesting notion. :thinking:

 

[ophiura]

The reality is that with urchins there is always some risk with soft corals. I would say it is rather low. But they may very well pick up items and frags and carry them around. That is normal behavior.

 

[reefkprz]

Originally Posted by ophiura
The reality is that with urchins there is always some risk with soft corals. I would say it is rather low. But they may very well pick up items and frags and carry them around. That is normal behavior.
I'd buy that. they are omnivorous by nature (as far as I know) I'm definatly not an urchin expert. I've seen the pics some one posted here of their urchin stealing their corals wearign them around the tank like a flowety hat. its pretty cool.
PLease excuse the typing one too many mojitos last night.

 

[renogaw]

Originally Posted by ophiura
There is always a risk to coralline, but some have proposed urchin grazing can help spread it.
hehe my urchin has corralline growing on it

 

[nereef]

thanks for the input guys. it looks like, however, that either in lab or in the transport over to my place the urchin met some rough conditions. spines have fallen off, and hermits are going to town on it.
as for birds and seeds, some tree (the name escapes me) depended almost entirely on the dodo bird for seed dispersal. its seed coat had to be partially digested for the seed to germinate. when the dodo became extinct, the tree almost did too.

 

[ophiura]

Sea urchins used for this sort of study are not often treated all that well. Depends on how long, or what sort of study, they were intended for.

 

[nereef]

Originally Posted by ophiura
Sea urchins used for this sort of study are not often treated all that well. Depends on how long, or what sort of study, they were intended for.
it was an hour or so lab examining urchin gametes. the urchins are injected with KCl. this causes a release of sperm or eggs, which can be combined and examined with a microscope. how long they were out of water, water conditions, handling stress, etc is unknown to me. urchins don't poison their surroundings at time of death, do they?

 

[ophiura]

Nope, no more so than anything else dying.

 

[nereef]

thanks.