bristle worm attack

[jchump5415]

Dr Ron,
It was not a good morning this morning when I woke up and found a foot long bristle worm exteding from a rock to the bottom of my tank raised deresa clam that I have had for one year. When I tried to catch the worm he went all the way up into my clam. Of course the clam was toast with gobs of mucous around him and he was dead. I threw them both in the trash. Now I am concerned about my 6inch tank raised blue maxima. I have had various other clams die in the past years and I wonder if these worms were the culpret. The clam had been doing great. Have any suggestions?
Thanks,

[RobertK]

Jen,
Sorry I don't have an answer for you, and please forgive me for jumping in, but I thought I'd ask the good doctor a related question. The other day I saw an 8-12" brown and white bristle worm eating a baby Strombus alatus snail in my tank. I'm not sure if it killed the snail or if the snail died for another reason and the worm was dining on the carcass. Should I try to catch the worm? Last year I found a similar worm eating some coral polyps and had to remove it.
Thanks,
Robert

[JerseyReef]

Jen,

Read my earlier Thread (http://archive.reefcentral.com/vbulletin/showthread.php?s=&threadid=35766). You have a polychaete called Oenone fulgida. Do a search on the web and you'll find some related info on them. They are very rare in the aquarium hobby, so not much is none about them. Both Ron and Rob Toonen have written articles and I believe it was written about in TRA 1 as well.

Good luck...

[chipmunk]

Can a large harmless bristleworm kill a clam by accidentally "hiding" in it? For example, if we tried to catch it, or maybe scared it by turning on the lights and the worm zipping into the first "cave" it saw? and the "cave" being the inside of a clam?

-chipmunk

[rshimek]

Hi,

If your worm was "blaze orange" and looked relatively smooth, and was relatively thin, it was Oenone and probably killed the clam. If so there should be a hole drilled in the shell. These worms are relatively uncommon - wrong - they are downright rare in our tanks - and I don't think that is what happened.

If the worm was pink, gray, or non-blaze orange, and had white visible patches of bristles on the sides of the body, it was being scavenged by a fire worm and had died from other causes.

I suggest your clam died from other causes, most likely starvation (which is the major cause of clam mortality in our tanks, I think). Small clams, those around 4 inches and less in size get the majority of their nutrition from feeding and need a lot of food to do well. They eat phytoplankton, and without sufficient plankton they will often live on stored energy for a few months to a year before succumbing in our systems. Clams need a lot of food, an unless they are being adequately fed they will generally die in our systems.

Robert,

The worm was a scavenger doing its job. It was a fireworm and these don't eat live snails.

Chip...

Fireworms won't go into clams, and the clams won't let them go there. Simply won't happen.

[RobertK]

Thanks, Ron. You da man!

[jchump5415]

Dr Ron,
I believe that the bristle worm was pink but the lights were off in the tank and we only had a small light on in the room to not scare off the worm so we could catch it. I really could not get a look at it after we got it out of the tank because like I said it squeezed up into the dead clam. I did not notice any type of hole in the shell of the clam. I add quit a bit of phytoplankton, but run a uv sterilizer off and on when I add new livestock so that depletes it. I certainly hope it was not this rare Oenone or one will probably get a taste of my $100 large tank raised maxima:mad:. Thanks for the advice Ron. I will certainly spy on my tank for another large sucker like this.
Thanks,

[rshimek]

Hi Jen,

Good luck!

Tridacna need a lot of light for their zoox to work well, and a lot of food in any case when they are small. Once they hit about 5 inches long, the zoox become relatively more important than they did at smaller sizes, but food is still important, and these critters can require a lot of it.

The larger pink, relatively "fat" worms with evident tufts of white bristles are harmless scavengers.

:D

[ReefRaf]

Just to add to this, I currently have one of these worms in my tank. My best estimate has it at over 12inches. This worm is systematically cleaning out my snail population. It attacks and drags the snails back to the rock it lives in. I find slimed snail shells there weekly. Two in one night last week. All the snails so far have been cerith snails. I put a piece of squid in a test tube and placed it about 8 inches from the rock. I came back 20 minutes later and the test tube had been draged back to the hole in this rock...strong worm! It doesn't so much have bristles on it; more like spikes or barbs. The coloration is a monochrome orange. If I don't catch it by the week-end, I'll be pulling the rock from the tank and digging for it.