Do I have a mantis ?

Agu

Premium Member
Do I have a mantis? I've had several fish and shrimp "disappear" over the 18 months my 180 has been setup. I've been using jars, pop bottle, and the exterminator traps for two months. Right off the bat I caught two crabs, but then nothing. Since then I've lost two peppermint shrimp, two emerald crabs, and a 4" purple tang. I've never seen a mantis in spite of searching the tank at all hours of the day and night (Honey, what the heck are you doing ?). I've never heard the tell tale click of a mantis. I've found plenty of empty shells, but none that appear to be busted up. And I can't find anyplace that would appear to be it's lair.

Am I just being paranoid ? Any other ideas or hints on finding and catching a mantis? I still have 6 green chromis, a firefish, a sixline wrasse, two cleaner shrimp, a couple of brittle stars, a cuc, and a 12" bristle worm (which I discovered while searching the tank one night), and haven't lost anything in a month.

I've even considered tearing the tank apart, but with no clue if it's even in there, let alone where to look, that doesn't seem like a smart idea.

Agu
 
Yes, I think you have a mantis. I finally saw a mantis in my 40g after feeding with live brine shrimp. Try feeding with that and then pull up a chair and watch. If you've tried the traps and soda bottle trick all I can think of is the live brine shrimp and keep trying with the traps. If you can find a cheap supply of crabs, or snails that should keep it from eating anything more expensive until you can catch him. Good luck.
 
Can I ask for a second opinion ;)? Noticed the cerith snails have been dropping like flies, is it dining on them instead of the food in the traps?

Agu
 
hi agu

i does sound kinda like a mantis and these buggers can seriously hide when they want to. here what i suggest!

1. look for little piles of sand around rock bases that might indicate a burrow (if you find one then target feed that area and see if it comes out)

2. look for natural caves in liverock (mine loves these). they can get into some small space if they want too!

3. keep trying the traps (but maybe move them around to different area and hope for the best). from what i hear those traps catch nearly everything else before they catch a mantis!

4. make sure there is nothing else that might be capable of doing that damage first! (filters, other animals, etc

5. did you recover any of the dead animals (beside the cerith shells)or did they dissapear all together. (if you did find a dead fish did it have any smashing wounds that look like it been clubbed?)

6. maybe bait a trap with a cerith snails (you never know?)

also:
mantis are fairly shy critters and it might be picking on the cerith because they are walking by his home and are an easier source of prey than having to come out to feed on the traps.

can you take the cerith out for awhile and hopefully with his food source gone he will try the traps?

i have ketp mantis for awhile now and ive never heard any of mine click during the night? so there might be one there!

if its killing 4" fish it would have to be fairly large and i doubt it would have eaten the whole fish, so some remains should have been found? (unless it was eaten by little critters or the mantis buried it?)

i wouldnt rip your reef apart unless your sure its a mantis

keep searching and i hope you catch him! (if its a mantis)

well thats all i can think of at the moment.
hope i helped a bit?
good luck with the hunt!

p.s paranoia is good!................. that mantis is watching you!
 
I've found a possible hideout!! A hole in the rock at the back of the tank that looks like a tunnel. Unlike the other holes this one has sand on the bottom, even though it's a couple of inches above the sandbed? In addition, that area has a bunch of mini featherdusters and the duster directly above the hole is often closed up while the rest of the dusters are out. It would appear something irritates that one duster without bothering anything else in the area. Sound likely, or am I just deluding myself?

I'll "only" have to take out 20% of the rock to get that one out. What are the odds it'll bail out and hide elsewhere if I attempt to remove that rock?

Agu
 
sound promising agu!
id make sure its their before taking out the rock though!

try and lure it out with a bit of meaty food on a skewer and hopefully youll get a visual on the mantis.

how hard would it be to have a net right near the rock when u lift it?
is there other rocks around that will cause some obstruction?
 
Agu, all that advice Isfrael sounds very good from my mantis experience.
My Mantis was very small (~1.5 in.) a was able to kill fish much larger than himself... the person who has him now says that they only hear the "crack" when he is breaking up his pellet food.
He can swim well enough to get even a fish that sleeps in the water column, if he's really hungry.

We NEVER saw ours until we bought a trigger fish ..the trigger was always rooting around killing everything he could get to -- when he knew something tasty was living in a spot in a rock, he would religiously "terrorize" that spot always trying to get at whatever it was living there, so IMO he basically flushed out the mantis and we were able to catch him because the mantis was paying more attention to the trigger than to us.

It was hilarious to watch the mantis hide on one side of a rock waiting for the trigger to go off in the wrong direction so he could then escape off to a favorite hole. The trigger was one smart fish, and I have no doubt that he would have eventually figured out the game.

The cracking sound--- We have had the ominous "crack" in our tank since the first live rock. I don't think it was ever the mantis in our case... In our search for him , we caught at least 4 pistol shrimp... I now believe that we have a breeding colony of social pistol shrimp. I isolated some of them in a separate container and discovered that they "crack" all day . They crack to scare food, they seem to crack in communication to each other also (maybe pecking order stuff --who knows) - they are also quite reclusive and somehow seemed to be able to avoid predation by the mantis. I still have this sound coming from my tank and the bicolor blenny( who would be the most vulnerable) has been fine (so far)

I hope this hasn't been too boring -- I am just trying to offer you info that might help you figure out what's going on in your tank:)

None of the various traps ever worked for us , but they we may not have been diligent enough in that dept. I think he was living quite happily on pods and maybe the occasional pistol .

Our tank sat fishless with no water changes for about THREE YEARS with only the mantis & the green brittle star (who we now assume may have killed some fish also) -- The brittle was fed ~once a week and I'm sure he never left any food for the mantis.

IMO, if you've ever wanted a predator tank, this is the time to make the change!! What a good excuse, right? You have to save those fish... Set up a new tank, move the fish and put some triggers and puffers in the 180!! That trigger we had was the coolest fish -- we still miss him! But there is no way I would keep even a tiny one like ours in a 30g for very long.:(

Anyway, if you're still awake, good luck!

One tip -- whenever we knew what rock he was on and tried to remove it, he would swim off of it on its way out of the tank -- if only our 6-line wrasse had been so smart! ( That was exciting, but he was ok after we put him back in the tank)
 
Agu, all that advice Isfrael sounds very good from my mantis experience.
My Mantis was very small (~1.5 in.) a was able to kill fish much larger than himself... the person who has him now says that they only hear the "crack" when he is breaking up his pellet food.
He can swim well enough to get even a fish that sleeps in the water column, if he's really hungry.

We NEVER saw ours until we bought a trigger fish ..the trigger was always rooting around killing everything he could get to -- when he knew something tasty was living in a spot in a rock, he would religiously "terrorize" that spot always trying to get at whatever it was living there, so IMO he basically flushed out the mantis and we were able to catch him because the mantis was paying more attention to the trigger than to us.

It was hilarious to watch the mantis hide on one side of a rock waiting for the trigger to go off in the wrong direction so he could then escape off to a favorite hole. The trigger was one smart fish, and I have no doubt that he would have eventually figured out the game.

The cracking sound--- We have had the ominous "crack" in our tank since the first live rock. I don't think it was ever the mantis in our case... In our search for him , we caught at least 4 pistol shrimp... I now believe that we have a breeding colony of social pistol shrimp. I isolated some of them in a separate container and discovered that they "crack" all day . They crack to scare food, they seem to crack in communication to each other also (maybe pecking order stuff --who knows) - they are also quite reclusive and somehow seemed to be able to avoid predation by the mantis. I still have this sound coming from my tank and the bicolor blenny( who would be the most vulnerable) has been fine (so far)

I hope this hasn't been too boring -- I am just trying to offer you info that might help you figure out what's going on in your tank:)

None of the various traps ever worked for us , but they we may not have been diligent enough in that dept. I think he was living quite happily on pods and maybe the occasional pistol .

Our tank sat fishless with no water changes for about THREE YEARS with only the mantis & the green brittle star (who we now assume may have killed some fish also) -- The brittle was fed ~once a week and I'm sure he never left any food for the mantis.

IMO, if you've ever wanted a predator tank, this is the time to make the change!! What a good excuse, right? You have to save those fish... Set up a new tank, move the fish and put some triggers and puffers in the 180!! That trigger we had was the coolest fish -- we still miss him! But there is no way I would keep even a tiny one like ours in a 30g for very long.:(

Anyway, if you're still awake, good luck!
 
Uh -- I hate to put another post on here --- Don't know what happened above???

It turns out that my theory about the social pistol shrimp was pretty much wrong... caught another mantis yesterday:rolleyes:

Learned something from Gonodactylus, you may already know, mantis shrimps are usually diurnal -- all that night time flashlight hunting was interesting, but a waste of time searching for a lurking mantis....(next time I'll look for a hole stuffed with sand)

I know this is correct with the one I caught - it spent almost 2 hours piling up rock to cover his hole for the night

Both of the two I have caught were early afternoon -
Good luck:)
 
Daily activity

Daily activity

Whether a mantis shrimp is diurnal, nocturnal or crepuscular (dawn and dusk) depends on the species. Most of the species of mantis shrimp that people keep are diurnal. That includes almost all gonodactylids and pseuodsquillids. Even here, there are definite peaks of activity during the day. A typical gonodactylid (Gonodactylus chiragra, G. platysoma, G. mutatus, Neogonodactylus wennerae, etc.) opens its cavity at dawn, forages actively for a few hours and is more likely to stay in the cavity around 10-2. Then there is another peak of foraging and the animals begin closing up their cavity just before sunset. In the field, tidal cycles and alter this pattern.

Odontodactylus scyllarus is a bit of a puzzle. They are primarily active during the day, but also come out at night, particulalry when there is a full moon. They usually do not seal their burrows on a daily cycle.

A few people are starting to keep Lysiosquillina. They hunt day and night, but usually don't leave their burrows.

Echinosquilla from Hawaii and the central Pacific is one gonodactyloid that is crepuscular. You don't see them in their burrow entrances until dusk, then they move to the entrance and you start to see eyeshine from a dive light.

If you don't have an Ondontodactylus scyllarus and you hear clicking in your live rock at night, you can be pretty sure that it is not a stomatopod. The most likely culprit is a snapping shrimp.

Roy
 
Gonodactylus - thanks for more specific info - the clicking in my tank was during the day -- so far now I have only heard it from the new mantis tank... I know this is extremely subjective, but I think my fish seem more at ease especially the blenny and the fire shrimp -- could be my imagination or a coincidence..

That little mantis is quite an interesting fellow - anybody know which sunglasses to buy that have some kind of filter that enables seeing the "flashing" that some of them do?
 
You need a polarized filter to see the uropod polarization of species like N. curacaoensis and N. wennerae. A pair of polaroid sunglasses should work.

Roy
 
Thanks!! I'm guessing that my little mantis is neither one of those species... but I'll check it out anyway --

My mantis is very dark - mostly all over including his eyes (makes sense) - but he has some very bright turquoise coloring in front that he can arrange to make it look like 2 big eyes and then he moves his legs (or something) in a way that gives the appearance of a fish opening his mouth very big in a threatening manner -- I assume that behavior is reserved for mantis predators? (What would wrestle with a mantis...:rolleyes: - guess that's why the fish he is appearing to be is much larger than he is)

I would guess that he has some special behavior reserved for other mantis shrimps

I am amazed at how busy he is with his little rocks - very fastidious.

I guess I will find something live to put in with him that he can hunt.. don't want him to get depressed -- LFS doesn't sell "Mantis Prozac" (yet):D
 
The display that you are seeing is a threat. THe stomatopod spreads the raptorial appendages wide, raises its head, and extends the other maxillipeds (mouth appendages). The antennal scales usually held out perpendicular to the body as well. Threat displays are given to both predators and to other stomatopods. The only difference is that when the stomatopod displays at a potential predator (or competitor for its cavity), it usually raises the head making the display look as large as possible. When displaying to another stomatopod, the display is directed more at the opponent.

As for the species that you have, the colors that you describe sound like Gonodactylus smithii, a common reef flat stomatopod from the Indo-Pacific. There are two characters that are unique to this species. The first is the color of the meral spots (the "eyespots" inside the striking appendages). In G. smithii they are deep bluish purple surrounded by white. Also, at the base of the uropods, the appendages that extend out from the tail, there is an orange spot on each side. No other stomatopod that I know of has these species specific colors.

Roy
 
Gonodactylus - thanks for the continued information! I can't tell you what a treat it is to be getting such expert consultation about my little mantis! Didn't realize at first that you apparently study these incredible creatures -- before I caught the first one, my plan was dispose of it in the manner that pests usually are:rolleyes:

But in my quest to catch him and seeing what he was able to do to my fish, I wound up with nothing but awe and respect for these amazing predators - as is often repeated: it's a good thing they are not any BIGGER:eek1: !!!

Will pry the dig.camera from my husband long enough to get some photos of it - If you could make a positive ID, it would be most helpful to my 12 year old who is going to use the mantis for a science project -- probably something like food preferences or what induces him to unplug his hole in the morning - we noticed that if he is stacking up his rocks to plug his hole for the night, if the light gets brighter, he seems to reverse and start "tearing down" - any suggestions are welcome - BTW, is there anything you need to know :lol:?

Will take the description of G.smithii and examine him for similarities - he moves so fast- it's hard to get a look a his caudal end(orange?), and he seems to have figured out he doesn't need to do his absolutely gorgeous threat display:( However, I am not above holding up a little plastic trigger fish next to the tank:lol:
 
mantis shrimp

mantis shrimp

If anyone on this thread has a mantis they want to get rid but not kill please email me I am sure we can work something out
 
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