Nassarius Attacks Urchin

[Koa Mali]

I just introduced a tuxedo urchin to my tank. It was on the live sand bed, getting used to the neighborhood. Within two minutes, a giant nassarius crawled up the side of the urchin, probably attacking it. Two other nassarius were heading straight for the urchin.

I quickly knocked off the nassarius, picked up the urchin and placed it on a big flat ledge rock. I don't ever see the nassarius on the live rock, so I thought it would be safe. The ledge rock is balanced on two support rocks, like Stonehenge, where the snails would have to travel upside down a few inches to get on top of the ledge rock. Sure enough, a giant nassarius climbed up the support rock, crawled upside down a few inches, and made its way on top of the ledge rock. It stayed on the rock, sniffing the area for a while, then left the rock without attacking the urchin.

I thought the nassarius only ate detritus. The urchin seems healthy enough with pedicellaria actively exploring the area around it.

Am I going to wake up in the morning to a dead tuxedo urchin and four giant nassarius rubbing their bellies from a midnight meal?

 

[mscarpena]

Sounds a little off to me. Either the urchin is dying or they are not nassarius snails. I have never heard of snails attacking a healthy urchin. Also nassarius snails eat leftover food particles. I would return the urchin to the store.

 

[EllieSuz]

I have had a Tuxedo Urchin for years and have never seen my Nassarius Snails bother it in the least. Keep your Urchin; he won't spend much time on the sand bed. I only see mine there when he needs to pick up some more junk for cammo.

 

[SushiGirl]

Nassarius will eat anything that is dead/dying. I would guess the urchin was unhealthy. I had nassarius eat a dying shrimp (it was still alive when they started on it, and I couldn't keep them off of it).

 

[pagojoe]

Giant Nassarius may also show interest in stressed animals that are not dying. They are capable of killing quite a few animals, although I'm not sure how easy it would be for them to kill urchins.

Cheers,



Don

 

[StephLionfish]

Never underestimate them. I had some attack a lionfish one time. They'd get all over him, and he'd shake 'em off, they'd get back on...I had to take them back to the store! Imagine a small lionfish covered in 5 Nassarius Snails.

* the lionfish was not sick, and he's still alive and well, so he wasn't about to die. I do not think it is because your urchin is sick that they are climbing all over him*

 

[Koa Mali]

Thanks for your feedback. The tuxedo urchin survived, and the snails are not paying it any mind. It is sticking to the live rock, where the snails tend not to go. Maybe it had a piece of detritus stuck to it that attracted the snails, or that it was a new addition to the tank and, they were checking it out. We are at peace once again.

 

[mndfreeze]

Every time I add something new to my tank my nassarius come raging out and slime all over it, whether its a crab, shrimp, coral, etc...

Then they promptly forget about it. I assume its the 'smell' of another tank with food sources for them in it or dead stuff.

 

[SNAKEMANVET]

I have added a fish to my tank and the nassarius snails would pop up out of the sand looking for it.

 

[C0rp]

I added stomatella snails to my tank today and my nassarious snails hunted them down and ate them. Well, they ate one before I realized what was going on and put them in the sump.

 

[Tankdiver83]

They like to explore new smells whether that is putting your hand in the tank, food or a new creature.