What would go after a brittle star

[Brenden]

I turned my lights on this morning and one of my brittle stars was out in the sand. He was missing 3/4 of one leg 1/2 of another and the tip off a third. He is about 8" across. I have a few small crabs in my tank. largest is approx size of a quarter. Only other thing I can think of is I hear a mantis or pistol every so often. Would they go after a star? Any idea what it could be?

 

[seafan]

It is possible, crabs would also do it, especially bigger ones.

 

[Brenden]

The largest crab I have that I know of is a emerald crab and he is only about the size of a nickle or quarter but he has tons of food to eat.

 

[Hara]

It is also possible that nothing went after him and the legs came off from a necrosis due to an infection of some kind.

 

[Fluff]

Is it possible that some of your rock shifted and trapped him? If everything in the tank is ok and the star is healthy, they will grow back.

 

[Brenden]

I have not moved any rock around to trap him. The injures/breaks looked like "clean" breaks. He seemed healthy when the lights came on he hauled butt into the rocks. I regularly see some of my serpent stars and they look fine. I will keep a eye out for him. Would a mantis bother a star? Do not know if I have one or not but I have heard popping. Hopefully it is a pistol.

 

[MT79]

Ammonia and nitrite will cause tissue necrosis. Have you been monitoring the water parameters since adding that last batch of LR?
It very well could be just a crab-I don't think a mantis would do that.

 

[steve-s]

Hopefully it is a pistol.

Actually better off being a mantis if you had a choice. Pistols are very undescriminating about what they eat. Anything that enters/happens by their burrows is fair game. Corals, fish, you name it. Mantis are moreso crustacean predators.

Cheers
Steve

 

[MT79]

Hopefully it is a pistol

I forgot to mention-if my serpent star sticks his arm in my pistol shrimps burrow looking for food it will do that to it. The star usually heals fairly quickly. FWIW the pistol does not bother my Linckia star though.
Edit: Steve-S beat me to it lol.

 

[lando]

Interesting question. I must have between 200-300 britle stars in my tank of vairying sizes. A lot of them are not complete, missing a leg or two. Never really wondered why until now...

 

[mjvincent]

Interesting question. I must have between 200-300 britle stars in my tank of vairying sizes. A lot of them are not complete, missing a leg or two. Never really wondered why until now...

How big is your tank? Can I come over to see ?

 

[lando]

72gal. Seriously, they are everywhere. 200-300 is a very rough estimate. I recently got back from vacation and had some algae on my glass. I counted over 100 just on my overflow and glass. makes me wonder how many tiny ones are on the 150lbs of LR I have. Its like the more you look the more you find.

 

[Brenden]

What ever the problem is it has eaten into its body now. It is on its death bed.

 

[MT79]

Sounds like a water quality or acclimation issue. Was it a LR hitchhiker? If so I would not sweat it. The shipping process is rough on stars-being out of water, cold temps. etc. Also did you test your Ammonia, nitrite and nitrate levels lately?

 

[Brenden]

He was a survivor from the package that UPS left in the sun. It looks like something was tearing him apart. It was into his body and some brown gunk was coming out of him, He was still moving but I went ahead and put him out of his misery. Can something like this happen from the temperature of being left in the sun? What in water chemistry can cause this?

 

[quarryshark]

Can something like this happen from the temperature of being left in the sun? What in water chemistry can cause this?

Maybe the stress from being left in the sun.
How long did you acclimate him for? I would say that is usually the problem with stars.

It looks like something was tearing him apart. It was into his body and some brown gunk was coming out of him

definitely not a predator, thats how they die.

What in water chemistry can cause this?

any trace of ammonia, or nitrite, too high nitrate, low PH....basically anything less than perfect water quality. These type of inverts are the "barometers" of water quality.