C. pictipennis Nymphs Dying Off

[Sceliphron]

I am very new to keeping mantises and have been experiencing some extremely high mortality rates with my creo nymphs: out of the 9 L3 nymphs I started with I have already lost 5 since the past two months, 3 L3 and 2 L4s.

They started out on FFFs, then as they molted into L4 ate wild-caught hoverflies, houseflies, and greenbottle flies for a week, and are now eating captive-eclosed houseflies. They have also eaten honey and bee pollen on occasion. They are misted once every 2-3 days. Below is a picture of an individual mantis's setup (the lid is a coarse fabric mesh). All the enclosures are kept inside an large, shallow, open cardboard box, so they are relatively dark throughout the day. As it is winter here, temperatures have been relatively low, around 60-70, and occasionally drop below 60 on an especially cold night.

The last creo to (almost) die was today, and which I took it out for inspection, the mantis suddenly underwent some violent spasms for a second or two before returning to a lethargic, almost lifeless stage, which it is currently in. It is showing no signs of mismolt, starvation, or injury.

Since it recently ate a hoverfly, I'm thinking pesticides, but does anyone have any ideas? Thanks!

 

[AxolotlsAreCoolToo]

I have heard tremors could be from exposed to somthing toxic. Maybe stay away from wild prey caughts or test them on spiders. Is there enough ventilation? Its really important.

 

[kingmatt]

they are in a huge cup ry a little smaller

 

[hibiscusmile]

They need misting every day, the room is to dark and cold. They need minimum 72F or better, set the cups on a cable dish or tv that lets off heat, they need a good 10 hrs of daylight, maybe less, but try to mimic their natural environment. Cold, dark, no moisture is the problem.

 

[iLUVdraguhns]

yeh try a smaller cup. the bigger it is, the harder it can find food..

 

[Extrememantid]

The cup size doesn't really matter.. They aren't in a huge enclosure.. It appears there is a lack of ventilation.. As well as there might be possible chemicals on that fake plant, give the whole container a thorough cleaning and make sure there is a good amount of ventilation.

 

[Shadow]

Has it been used as a fish decor I have one that looks like that

 

[Krissim Klaw]

Something is off if you are loosing that many. I woudn't blame the cage size since by that photo they are clearly getting enough to eat. Ventilation could be a problem and an easy way to see if that is the issue is to add some screening to the sides for better ventilation. Personally, I like to mist/offer water daily. The drops should dry up within an hour or so. If your cage stays wet for long stretches after misting than this is a great sign you don't have much ventilation.

Pesticides could be an issue if you are feeding wild food. Did you loose the other ones after feeding something wild caught?

Finally, I do think you are keeping them awfully cold. They are flower mantises who are built for the warmth. I would try to avoid letting it dip below 70degrees. Also, please don't keep them in the dark all the time. They really need light during the day (it doesn't need to be anything special bulb wise) and then darkness at night so they can have a proper circadian rhythm.

 

[Sceliphron]

Mantises have been moved to a sunnier area (no direct sunlight!) and are now being misted daily. None of my other mantises suffered from eating wild-caught flies so if pesticides were an issue I might've just gotten an unlucky individual. Either way they are now eating captive houseflies so I am no longer worried about the pesticide issue. The entire top is essentially mesh, so ventilation is probably not a problem. The cages dry relatively fast.

Still not sure what to do about the heating issue, did not expect temperatures to drop this low this year. I've crammed most of the enclosures next to the mini heat mat stuck to the side of my desert hairy scorpion enclosure. I don't think the enclosures being this large is an issue, since I take personal care that each mantis manages to eat during feeding, unless there is another factor I'm unaware of (I've read that the drop height if a mantis loses its footing during a molt can be fatal)?

The plants are indeed old fish decor that have been used in a tank for about 2 years, so I would assume that any chemicals would have left by now?

I also have two sphodro viridis nymphs but they are healthy and very enthusiastic hunters.

Thanks for the help everyone!

 

[hibiscusmile]

Sounds good what u r doing now. I think the warmth will settle the matter along with the day / night time. I agree the chemicals are worn out on the fish items.

 

[Krissim Klaw]

Fish decorations shouldn't have chemicals on them to begin with considering fish are very delicate! It sounds like you have things headed in the right direction so hopefully the rest will prove to be strong and healthy.