How do I "spot" a mantis?

[ejmeier]

Ok, with the recent capture of a pistol shrimp in one of my tanks, things are beginning to clear up. I have two separate tanks, and I suspected each of them of harboring a mantis shrimp. With the first tank I heard clicking noises, and it turned out to be a Pistol Shrimp.

Now, with my second, I have not heard any noises, and I have not found any broken snail or crab shells, so that should rule out a smasher, right? The only thing I have to go on, the ONLY piece of evidence that I even have a mantis shrimp in this second tank at all is because of a molt found in my tank roughly one month ago. It was a a bunch of blue, shrimp-like legs, and a bluish green carapace.

I suspect that it was a hitchhiker on some of my liverock, or possibly on one of my corals. My live rock is from Fiji, the corals, who knows where. My question is: how will I ever SEE or confirm that I do in fact have a mantis shrimp? I have NO IDEA where he could be, only that the molt was in the LEFT half of my tank.

I know that some of you see your mantis shrimp at feeding time, but I have probably fed my tank over 500 times - from the left side I might add - and I have never seen anything unusual. Are there any tricks to getting your mantis to come out?

I also have a Ultralife X-terminator trap, but have not had any luck with it thusfar. Why would a spearer be dumb enough to walk into the trap in the first place? Is there a good bait to use with these traps?

Sorry for the barrage of questions, but I'm setting up a new tank soon, and I want it to be mantis-free.

Thanks

 

[lilswanwillow]

just going by that, you can't tell:
do you have hermits? they might moult, i think...
and shrimps? they moult....
yeah, i think you get what i'm trying to say...

 

[ejmeier]

I have one blood shrimp - he's red. I have some smaller hermit crabs, I have seen their molts and they're kinda brownish.

This was very unusual. It was a bright blue. I have nothing in my tank (that I can see) that is even close to this color.

 

[nts9]

my mantis's molt is clear in color, fwiw

 

[dwarfatize]

If you do have a small spearer mantis and don't want it I will take it.

 

[Sloth]

Here is what I did in my 15 gallon. I bet your tank is larger, so it will be time consuming, but should work.

I took a fishing line and attached a snap swivel. I put on a small piece of raw shrimp. Then I turned off all my pumps and dragged the shrimp all over every rock. Over every single hole and every single crack. If there is a mantis in there, it should go after the bait, either by hitting it or grabbing it.

Make sure your room is quiet so you can hear.