Mantis help?

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SaltyTemple

Well-known member
Joined
Aug 8, 2005
Messages
352
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Kirkland
Hello,

I've heard the clicking since we set the tank up in August, we've looked at night with the red light, and have NEVER seen it. Now I've noticed that my snail and hermit population is dwindling and hummmm I'm finding shells with holes smashed in them....hummmmm, Mantis much? :evil:

Anyhoo - since this is my first time and I'm still new to the hobby, I figured I would post in this wonderful forum full of smart smart people asking what to do and how to deal with this "situation".

I've thought it was my starfish killing my fish (jawfish, watchman gobie, random gobie), but could it be the elusive mantis?
 
The red lense trick will work on crabs but if you have a mantis, that won't work. Mantis have the most complicated vision of any animal in the world. In fact, most species can even see in ultraviolet, infrared, and polarized lights. Your mantis was likely looking straight at you wondering why you are shining a flashlight into the tank.Secrets of the Stomatopod

The fish were probably not harmed by the mantis (if you do have a mantis). Smashers don't typically eat fish if there are snails or hermits available to eat. In fact, I've kept fish in my mantis tanks before. I've never once lost a fish to a mantis but I have to a hitchhiking stone crab.

There are a number of home-made traps that people have used. One of the more common ones is to use a plastic soda bottle. You cut the top third of the bottle, invert the cone, and sew it back on. Then put some stinky meaty food in the bottle and sink it. You'll want to do this on a weekend so you can periodically check on it. If you leave it like that for too long, they will just swim back out. Here's another interesting trap made by James Fatherree. BTW...mantis are diurnal so there is no reason not to leave the bottle in there during the day too. Most people will tell you that you cannot trap them during the day. I've actually found early morning to be the best time to trap them.
 
Wow - thanks for that insight! I was wondering how they could be sleeping if I could hear the clicking. So I hear you say that I *may* have a Mantis. What else could be making the clicking sound and smashing my hermit and snail shells?
 
Clicking can come from many things. Mantis, pistol shrimp, hermit shells hitting the glass, some clownfish make similar noises.

However, the holes in the shells lend me to believe that you could very well have one. Do you find them collected around one particular piece of LR. Mantis typically take anything they kill back to their den and then when they are done eating, they kick the shell out of their den. An accumulation of shells in a particular area is one of the best ways to find the den.
 
Thanks for the insight on shell clusters. I'll go take a peek. We've wondered about that. It would be nice to hammer down where his "abode" is :)
 
Thanks Steve,

I lost a number of small branches and a couple of medium sized branches. My neighbor lost a couple of very large branches off of his Oak tree. They are selling their house and have already moved to their new house so I got stuck with the clean-up job anyway as they now live several hours away.

Shauna,

If you catch it, they are quite interesting animals when they are in a species nano tank. Here's some good info if you want to.

I like mantis and have kept quite a few species. I do want to correct some misconceptions because so many of them are killed unnecessarily by hobbiests.

You've all seen the posts before. "All 3 of my fish died...what could've caused it?" The answer comes back, "You must have a mantis". That is actually highly unlikely. Smashers can take out small fish but rarely do. I've even kept fish successfully in my mantis tanks. On the other hand, if your missing a small snail and you find a broken shell, you probably have a mantis.

First of all, while they definately do have the fastest movement in the animal world, most of the species that are common hitchhikers cannot break your aquarium or hand. It's simple Newtonian physics. Force = Mass x Acceleration. The smaller mantis have the acceleration thing down pat. However, they don't have the mass in their clubs. A fully grown peacock mantis can break small tanks and they can hurt you so keep your hands out of the tank. Unfortunately they are never hitchhikers.

I have had lots of different types of animals in my reef tanks. In the course of doing this, I have observed a lot of interesting critters. However, none have ever been more interesting than my mantis. Not only that, mantis have been the only animals that observe me back. I'm not talking about getting excited about being fed like cats, dogs, and fish...I'm talking about a quite intelligent creature studying me right back.

I have kept many species of mantis. Most hitchhiking species do not require an acrylic tank. However, if you want to keep my favorite species (Peacock Mantis) it will be a VERY good idea once it hits about 4~5 inches or so. If you have a small nano with very thin glass (like an eclipse) and you desire a medium size mantis as opposed to a small one, it is a very good idea to put a thin piece of plexiglass on the bottom of the tank before putting down a sandbed. Once they get into den building mode and they start banging, they could care less if it is rock they are banging or glass. There are species that are even larger than peacocks but I've never once seen them available to anyone other than scientists.

There is one thing that ALL smasher species of mantis requires even if it is a small hitchhiker...a titanium heater or a cage around a glass heater (unless your heater is in a sump). I can't tell you how many smasher-mantis have met an untimely death due to electrocution by hitting the ultra-thin glass used in most heaters.

It's real easy for me to advise you on a spearer tank. A VERY deep sandbed. That's about it. Unfortunately, you won't see a spearer very often in captivity and you won't get one as a hitchhiker because they don't live in LR.

For smashers, a good setup truly depends on the species you have and/or want as I alluded to above. I have had good results by creating a den for mantis using PVC tubing (size depending on species) and covering it with LR. You want the tubing to be 1 and 1/2 larger than full grown size of the mantis so they can turn around (and you will be quite surprised on how quickly they can turn around). Do NOT put the other open end of the tubing against one of the glass walls. They get into redecorating mode often (just like my wife) and if there is any type of barrier against extending their den, they may or may not decide to keep banging on it until they get through. Remember, they get stronger as they get bigger. Your specimen may not take to your den at first because you will have placed it in such a way as to maximize view. However, I've found that once you become known as the "bringer of food" and they are more comfortable, they will accept this new den. Regardless, I've found that they will make a secondary den too. Provide shells and small pieces of rubble for them to decorate, and re-decorate, and re-decorate, ad-infinitum.

Why hyper-salinity dips don't work to remove most mantis.

Many mantis live on patch-reefs and intertidal zones. When the tide goes out for half of the day, the water pools, evaporation happens, the temperature in the tidepool increases substantially, and the salinity continues to go through the roof until the tide comes back. They are accustomed to this type of abuse.

Where did my mantis go? He's been doing well for months and he/she put a whole bunch of rubble in front of the den and I haven't seen it for days.

It's molting. They have an exoskeleton and eventually their tissue size will outsize it. They have to shed it in a similar manner to shrimp. Leave the molt in for a day or two. They will often eat it for calcium, strontium, and other needs. Then discard it. BTW...the molt on the first day will be an EXACT duplicate of your mantis. Unfortunately, just like in nature, this is the most likely time to lose a mantis.

Should I add Iodine to help my mantis shrimp molt?

Heck no. Mantis shrimp are not shrimp, they are stomatopods. However, this is one area where they are similar. Just like shrimp they have an exoskeleton and adding Iodine MAKES them molt, it doesn't HELP them. If you force them to molt too early, you are severely weakening it.

How do I make my mantis like me?

All living things have an innate instinct for security, food, and procreation. Provide them with a secure den, and from the beginning don't allow any natural foods for a while. You need to provide it. Once they feel secure, you will then become the "bringer of food". It's not a good idea to put more than one mantis in a nano because sexing them is hard to do unless you are holding onto them. In nature, mantis of the same species and sex merely engage in "I'm tougher than you" contests like rams and they both walk away at the end. However, in a small nano tank, there isn't sufficient retreating area. In other words, don't try to breed them unless you are SURE of their sexes. Most species breed with the same partner for life.

I understand that in nature, some critter is always eating another critter to survive. However, I cannot put something in my tank that might be killed.

If so, then a mantis probably isn't a good animal for a species-tank for you. If you have a smasher, once you earn their trust, you will have to start adding a clean-up crew. If mantis don't exercise their clubs, they will lose them in the next molt. With feeding of your mantis, most of your clean-up crew will be left alone. (They are quite intelligent and prefer free food over food that requires work). However, they will slowly one by one disappear over time.

Should I put my hand in the tank?

I'm quite popular in St. Louis when someone has a mantis. That's because I will grab SMALL mantis out of a local reefers tank with my bare hand. They will back up from it like I pulled out a lion or a grizzly bear. Being afraid of a 1 inch G. wennerae as opposed to an 8 in peacock is like being terrified of kittens because lions have killed humans before.
 
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Wow - this has been so insightfull! I am so grateful for the in depth knowlege you have both been able to impart. I am much less concerned about my clicker now! I will continue to feed the tank and replentish my cleaners. No worries :) And I thought the culprit for my disapearing stock was my sallylight foot crab (still could be) I may look into keeping one in a nano tank. I love it when the critters are genuinely interesting. I had an Oscar for a couple of years who used to watch me wake up in the morning and start wagging like a dog. He also let me pet him and would hide when anyone else came in the room. He was cool.
 
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