Pistol Shrimp Killing things?

[PeterC2904]

Hello I’m hoping someone can help me out here, I have a pistol shrimp that I’ve been told is bigger than usual ones, I’m not sure what kind it is exactly but it’s red with purplish legs. Anyways in the past 3 weeks I’ve lost 3 fish and everytime I notice one missing I look in my pistol shrimps den and see him eating them. I know they possibly could’ve died from something else but I’ve done tests and my water quality is all good. On top of this I woke up to the sounds of it’s snapping and saw it had a hold of my firefish and it was basically dragging it to its den. I managed to get him to let go of it but what threw me off was the fact that the firefish was still alive and he was completely fine all day. I’ve been told pistol shrimp don’t attack other fish but at this point it’s the only thing I can think of that’s been killing my fish, and seeing it attacking my fire fish further makes me believe that. If there’s something I’m missing or if it’s actually my pistol shrimp killing all these fish please let me know.

 

[JNalley]

Does it have any white dots? Or white tips on its claws?

 

[PeterC2904]

Does it have any white dots? Or white tips on its claws?

I believe so why?

 

[JNalley]

I believe so why?

Does it like ok like this?

Just trying to ID it before jumping to any conclusions

 

[PeterC2904]

Does it like ok like this?

Just trying to ID it before jumping to any conclusions

Kind of… it’s legs are more purple and it’s main antennae are alternating red and white colors

 

[PeterC2904]

Does it like ok like this?

Just trying to ID it before jumping to any conclusions

This is the one I have

 

[JNalley]

Well, I was hoping to get an ID first but I'm not certain which type of pistol that one is. The one I posted is a Japanese Pistol, and it is one of the larger pistols out there... Most of the time they go after crustaceans like snails, but they have been know to stun and kill fish, especially ones that get too close to its burrow... Mine tagged a couple of smaller Chromis but they made it away without being caught... It's entirely possible that one is killing off your fish... Some pistols even kill their Goby companions... Have you tried to directly feed it at all? If you can keep it fed it might stop hunting your fish, but that is certainly not a guarantee

 

[PeterC2904]

Well, I was hoping to get an ID first but I'm not certain which type of pistol that one is. The one I posted is a Japanese Pistol, and it is one of the larger pistols out there... Most of the time they go after crustaceans like snails, but they have been know to stun and kill fish, especially ones that get too close to its burrow... Mine tagged a couple of smaller Chromis but they made it away without being caught... It's entirely possible that one is killing off your fish... Some pistols even kill their Goby companions... Have you tried to directly feed it at all? If you can keep it fed it might stop hunting your fish, but that is certainly not a guarantee

Ya I make sure to feed it directly everytime I feed the tank, last thing I wanted was it getting aggressive and attacking my fish but I guess that ended up happening regardless . Honestly I’ll probably just bring it back to my LFS maybe get a smaller one instead. Thanks for the help man I appreciate it!

 

[JohnCol]

My pistol is usually a snail killer than a fish. But I have a different species than what you shared.

What els is in the tank livestock wise? How long you had liverock and where did it come from. Would be some questions.

 

[ISpeakForTheSeas]

This is the one I have

This shrimp is Alpheus armatus, the Curly Que Pistol Shrimp - I've heard of these shrimp causing problems before, and they may actually do so; I'm not sure if they're just more aggressive/predatory or if they lash out since we don't keep their host anemone. Either way, they don't seem to be safe like the goby-pairing pistol shrimp:

Actually, the Curly Que Pistol Shrimp, Alpheus armatus, doesn’t pair with gobies - it pairs with the Corkscrew Anemone, Bartholomea annulata, which tends to live in small cave/burrow-like structures (and A. armatus can find these nems even when they’re completely buried in sand).

A. armatus is considered an obligate symbiont with this anemone, so keeping it without one is likely incredibly stressful to the shrimp. Additionally, at least some of these Alpheid species (many of whose diets are inferred rather than properly studied) have been demonstrated to feed on the excrement of their goby partners, so it’s possible that this shrimp would feed on its host anemone’s waste in nature as well. If so, between lacking the safe shelter of its host nem and the (possible) lack of a major/primary food source, the extreme aggression would be much less surprising.

Edit: perhaps better terms than caves/burrows would be crevices, nooks, or ledges (more like mini caves than actual caves).

To clarify here, the genus Alpheus that pistol shrimps come from has some debate going about if it should be one genus or be split into three at the moment.

It's possible that some of the species (likely ones that would be put into a separate genus than the goby-pairing species if the genus were split into three) are more predatory hunters (which would probably prefer only hunting pods and the smallest of fish and inverts), but by all accounts I can find, the goby-pairing ones seem to be almost entirely defensive/territorial rather than aggressive/predatory - the goby-pairing ones seem to be omnivorous scavengers. The only evidence of "predation" I've seen involved a cleaner shrimp harassing the pistol shrimp at the end of the pistol shrimp's burrow. In fact, I've heard of multiple cases of the goby bringing the shrimp a small snail or hermit, the shrimp bringing it inside, and the snail/hermit crawling out of the burrow unharmed later.

(P.s. for an info dump on pistol shrimp diets and eyesight, click my username in the last quote here and it'll take you to the post the quote was pulled from - there's more info in that post.)