Nassarius snail attack

[shirty]

I've just seen my Nassarius snail try to take out my banded trochus snail whilst I was feeding corals.
The trouchus went crazy moving around in tight circles, then when I looked closer the nassarius was attached. A well placed hermit broke up the fight and the troucus managed to escape. The Nassarius snail then went in persuit chasing the troucus over the live rock until I netted him. For now the Nassarius snail will be sitting in the quarantine tank until I can be sure he's safe.

This would explain why I haven't seen 2 other trochus snails in the tank for a couple of weeks.

Has anyone else experienced this behavior? I thought these guys were scavengers not out right assassins :uzi:

Should I be feeding him?

 

[shred5]

My guess is it is not a Nassarius snail.. There are allot of snails that look like them...

 

[snorvich]

My guess is it is not a Nassarius snail.. There are allot of snails that look like them...

I agree.

 

[NMSREEFER]

There is a larger strain of nasarius. I had three. One day I dropped in a cube of frozen shrimp. When it hit the bottom the three large nasarius covered and consumed it before the fish could get to it. I didn't know they would attack other snails though.

 

[taricha]

Some people get wrapped up in the question of nassarius (good) vs whelk(bad).
Technically nassarius is a family of snails within the group of whelks.

You can attempt to identify down to the species level, but it can be very challenging.

The easiest way to ID detrivore vs predatory snail is simply to look at the feeding behavior and diet.

If I saw what you saw, that'd be enough for me to conclude it's not what I thought it was, and get it out.

 

[Umbra]

More than likely a similar variety of predatory whelk (although like mentioned above, Nassarius sp. are technically whelks themselves). Apparently there are several vendors across ebay/aquabid that are selling Ilyanassa obsoleta as Nassarius sp. so I wouldn't be surprised if there are local sources as well making the same mistake.

 

[Shawn O]

This seems like the same behavior I see in my Nassarius snails but I haven't seen them eating other snails. I think it's pretty normal for them. My smallest Nass chases the larger ones and either climbs on their shells or tries to get on their "feet", causing the other Nass to shake him off. I was watching them last night and another Nass was doing the same thing to a completely different Nass than the first pair. I think they're just horny snails or just like to mess with each other. The number of Nassarius in my tank has remained constant so I don't think they're eating each other. I've had an Astraea or two die but I think it was more that they ended up upside down and couldn't right themselves.

 

[mav3rick478]

I have 2 Nassarius in my tank and all they do is eat whatever food they can, once it his the water they rise like zombies from the sand. They are pretty clumsy though so it takes a while for them to find the food and get to it but once they're there it is devoured.

I have also witnessed them eat a Astrea snail and now a hermit crab but it seems they only go after the ones that are dead or on the verge of dying. I say this because they do not bother any of the other ones in the tank. Also yesterday I notice a hermit crab has been on a rock in the same spot for a few days but did rise up every once and a while, last night finally decided to see if he was still alive by moving him, turns out he was stuck in a hole in the rock and couldn't get out of it. Put him on the sand bed and he moved a little bit but definitely looked weak compared to the other crabs. He possibly could've been stuck for 2 weeks because we were on vacation the last 2 weeks. Come home from work today and both Nassarius are eating the hermit crab or at least taking turns trying to eat him. They stumble on each other and wrestle each other then go away to bury themselves and come back for more. They are pretty comical to watch when they do come out because they glide so quickly but always fall off rocks and wiggle like crazy and extend out of their shells trying to right themselves.

 

[cheesecreaper]

I also have two Nassarius snails in my tank, and I recently purchased six margarita snails that have been devoured by the Nassarius. ALL SIX ARE DEAD!!!!!

 

[GriffinMarsh]

I don't know which snails are my more favorite, nassarius or margarita. I have had large bouts of margarita keel over before. I always wondered if it was a temperature or acclimation issue. Now I wonder if I might have had a few different species of whelk?

 

[Dkuhlmann]

I also have two Nassarius snails in my tank, and I recently purchased six margarita snails that have been devoured by the Nassarius. ALL SIX ARE DEAD!!!!!

Like said above true Nassarius snails wouldn't do this, but the whelk will. They look an awful lot alike and some are sold as Nassarius snails by accident too often IMO. Ive got 6 of the small and two large Tonga Nassarius and they are great. Love watching the Zombies rise from the sand when I feed my fish.