mantis eggs!

[jsronce]

Our new female O. scyllarus has a batch of eggs this morning! (Figures, today is the day I was going to do a water change in her tank.) I went through this a few months ago with our first O. scyllarus but she ate them after a week.

Should I leave her tank light off all the time, or do regular light cycles? I don't know if she feels comfortable enough in her tunnel that seeing us watch her in a brightly lit tank wouldn't make her eat her eggs. Of course, being in darkness might be unusual enough to stress her, too....

We're hoping to get a chance to try to raise the babies this time! We still have the set-up we had made for the larvae, and I can get plankton from Puget Sound.

I'd appreciate any advice I can get!

Jennifer

 

[jsronce]

Here's a pic of the mantis with her eggs. The eggs are the large mass behind her on the ground. Sorry I couldn't just attach it, as the page still won't let me.

She must be feeling comfortable with the light, as she left her eggs on the ground several times while I watched to do something else! There isn't anything in the tank that can harm the eggs, and she knows it.

Jennifer

 

[jsronce]

Here's another pic. She's checking out the eggs that she's left on the ground in her tunnel.

Jennifer

 

[jsronce]

She's still got the eggs as of Monday night. However, she has removed a lot of rock pieces from the back wall she constructed in the tank, and now is making a FRONT wall to block our view of her! I haven't been spending much time in the room she's in, so I hope she hasn't decided we're a threat.

Just wanted to keep everyone up-to-date! Any suggestions are still appreciated. I want a crack at raising these babies.

Jennifer

 

[ADHybrid]

Sorry, I dont have any hard advice for you but from my experience with crustacians...their babies are pretty hard to keep. They will mate quite frequently and some females will store the sperm for later fertilizations so they are constantly having fertile eggs but most of the time (in captivity) the babies are either eaten by the parent or they die from inproper care (not that you would not care right for them....its just plain hard). I'm not even sure what baby mantis's would eat after the egg sac!!! If, however, you are succesfull at keeping some of the mantis's alive...please post your strategies, I know I would be interested!!

 

[DreamScape]

well, the babies are planktonic predators so you need lots of plankton. mybe keep then with heavy breeding snails?
good luck!

 

[jsronce]

I don't know anything about breeding saltwater snails! Is there a variety you can buy that will produce planktonic young often?

The first O. scyllarus I bought (last December) also produced eggs. She ate them after 6 days, but I wrote Dr. Caldwell and he gave me suggestions on raising the larvae. I have a 5 gallon bucket fitted with a spray bar and an overflow tube that I am going to connect to the mother's tank. I will try baby brine shrimp, but my main source for plankton is going to be Puget Sound. Anybody have suggestions for harvesting plankton?

If any live at all, they will cannibalize each other in the bucket. If I get any to survive to the point where I can identify and catch the little suckers, I may try isolating them, but I'm not going to try to figure out how until the eggs hatch.

Jennifer

 

[ADHybrid]

Well, your standard Turbo snail will breed quite often..if you wanna go that route. If your trying to find plankton...I believe KENT has a product that provides plankton for the standard reef aquarium. I'm trying to look for the name but all i'm finding right now is trace elements. I'll find it though. I got an Idea for the "canabalism" problem. Why dont you put some small porous live rock and large particaled substrate into the aquarium so the smartest and the strongest will hide and survive? Survival of the fittest?

 

[ADHybrid]

Found some!!!!

Two Little Fishies has a product called MarineSnow that is a planktonic food available for reef aquariums.

also, if you can get a Phytoplankton culture (dont know where or how ) you can use that to feed your babies continuously. you might try posting in the coral forum to see if anyone has a culture they could send ya. Some people have them for thier corals and filter feeders.



GOOD LUCK!!!


(keep us posted)

 

[jsronce]

Bad news. She ate the eggs last night. They only lasted 5 days.

She was acting real weird. She only had a scrap of them left when we checked, and was munching on them. After a bit, she came forward and threw them on the gravel (crushed coral) like she does with food she won't eat. Then she stepped up, moved her antennae around, and when she found them again, she literally pounced on them and picked them back up. She'd munch a bit, then toss them back out and pounce again. Talk about weird behavior!

Something must have bothered her, although I don't know what. She'd done major construction after she laid the eggs and made a wall of gravel and bits of live rock. She also changed around the exits from her cave. We hardly spent any time in the room during the day, and I kept the normal light schedule. The tank has a drip bottle for adding purified water, so there shouldn't have been any stress from that! I just don't know what we did wrong.

Jennifer

 

[ADHybrid]

Sorry to hear about your eggs. Maybe next time you should take them away from her and put them into a seperate rearing tank? I'm thinking that in the wild the current would take the eggs away from her so maybe that would be a good idea. I think mine is a boy so I haven't had the chance to experiment but if i get a female maybe I can help out in this field of study.

 

[jsronce]

It would take a very strong current to do such a thing, as female mantises cement all the eggs together into a mass that doesn't seem very bouyant, and guard them. From what Dr. Caldwell told me in the emails we exchanged in December, O. scyllarus females take care of the eggs for 2-3 weeks, cleaning them and removing any dead ones. After they hatch they will spend 24 hours in her burrow, then swim out into the current and become plankton.

I think it would be a lot like mouthbrooding cichlids. The females take care of the eggs, keeping them clean and aerated. If you have a female who consistently takes bad care of them, it is _possible_ to take the eggs from her and raise them, but it's very hard (and really, would you want to try to take a 6" mantis's eggs away from her? ). I've never done it, but I've been told it requires some sort of device to tumble the eggs around and often the eggs grow a fungus or bacteria that kills all the eggs if not taken care of quickly. So, leaving the eggs to be taken care of by the mother has a much greater probability of success.

If I'm going to try again I will have to get a male. Both of the failures could be due to infertile eggs. However, I'll need to set up another tank for that, and it's not very high on my list of priorities right now.

Jennifer