Fox moth overwintering (1 Viewer)

[socksitis]

I have a question regarding Fox moth caterpillars. I understand they overwinter, emerge and then pupate. This last week I found two things, one was a fine, long cocoon, empty, then I found the same with a Fox moth caterpillar halfway in or out, I thought it was dead - no movement, then when I checked again days later, it was alive.
My question is - do the caterpillars overwinter in this fine cocoon as caterpillars with no change?

 

[harry eales]

I have a question regarding Fox moth caterpillars. I understand they overwinter, emerge and then pupate. This last week I found two things, one was a fine, long cocoon, empty, then I found the same with a Fox moth caterpillar halfway in or out, I thought it was dead - no movement, then when I checked again days later, it was alive.
My question is - do the caterpillars overwinter in this fine cocoon as caterpillars with no change?

Hello Socksitis,

The larvae of The Fox Moth hibernate in deep moss that is usually found over most of it's habitat. It is reputed to be very difficult to overwinter in captivity but as I have shown elsewhere if the correct conditions are provided there is no difficulty in rearing them at all.

From February through to late April the post hibernated larvae can be seen sunning themselves, in an exposed position during the few periods of sunshine we get in the early months of the year. They do not feed after emerging from hibernation. When the larvae is ready to pupate it sping that long greyish brown cocoon in which it pupates. These cocoons are eagerly sought out by many birds, especially those of the Crow Family who cannot manage the hairy larvae but enjoy the pupae. The empty cocoon you found had in all probability been robbed of its pupae by a bird. The larvae do take their time in cocoon construction and this period may last several days. Good luck with your specimen, they're a beautiful moth when freshly emerged.

Harry

 

[socksitis]

I have been out to check on the progress, I now have an empty cocoon case, where I left it, so nothing has taken it away, I still think the caterpillar was on it's way out and not on it's way into a cocoon, I thought they built them around themselves? Not had an empty case to struggle into?
I have attached a picture of the first flimsy, gosamer type case that the catapillar left behind and another 'proper' cocoon that I picked up recently, I thought the latter, smaller, tougher case was where the pupae changed?
I would appreciate any advice on this - how would I determine what has been where. I suppose it is a case of keeping them in activity. Harry, when you have kept them have you seen them when they are in the leaf litter? On the moorland where I have seen them during the year I would say leaf litter is not about as to the grass? Then maybe they do go down into the matgrass and molinia?

 

[harry eales]

I have been out to check on the progress, I now have an empty cocoon case, where I left it, so nothing has taken it away, I still think the caterpillar was on it's way out and not on it's way into a cocoon, I thought they built them around themselves? Not had an empty case to struggle into?
I have attached a picture of the first flimsy, gosamer type case that the catapillar left behind and another 'proper' cocoon that I picked up recently, I thought the latter, smaller, tougher case was where the pupae changed?
I would appreciate any advice on this - how would I determine what has been where. I suppose it is a case of keeping them in activity. Harry, when you have kept them have you seen them when they are in the leaf litter? On the moorland where I have seen them during the year I would say leaf litter is not about as to the grass? Then maybe they do go down into the matgrass and molinia?

Hello Socksitis,

All the larvae I have bred from the Northumberland and Durham moorlands have come from areas of peat based moorland where where Heather upon which they larvae feeds grows over Sphagnum Moss, below that is wet peat. My own experience is that the larvae appreciate the dampness of the Sphagnum Moss as a hibernation site. The wet peat is never used as a hibernation medium being too wet and the top cover of Heather is too exposed to the elements. I have never observed a cocoon or hiberniculum for the larvae to overwinter in. The only time they spin up a cocoon is when they are pupating. I have had an average of 99% sucess in rearing this species from ova, and overwintering it sucessfully.

Having no experience of the larvae overwintering in different conditions, or amongst different plant species, I can't really comment on how the larvae may perform in such hibernating substrates. Sorry.

Regards,

Harry

 

[socksitis]

Thankyou Harry, I will have to learn to look better and hold on to things, not put them in the bushes in the garden!

Ann

 

[Hantsmoffman71]

Rearing Fox Moths

Harry

I have about 25 fox moth larvae that are heading towards full size and am trying to decide whether to release or whether I can find out the right conditions to keep them through to adulhood. Your posting here on Bird forum is the only reference on the whole internet to someone knowing how to achieve this.

Could I ask for the details of how you get them through the tricky larvae hibernation process. I can then decide if I can see the job through or take them up the forest for release.

Thanks in anticipation.

Mark

 

[Oleander]

Hi Mark. I asked the same thing two years ago and Harry gave me a very informative answer, here's that thread:

http://www.birdforum.net/showthread.php?t=150739

 

[harry eales]

Hello Mark,

Just go to the URL provided by Oleander and follow the instructions. You can make the net sleeve out of material available from ladies dress making shops a simple seam up the side will suffice/ Tie one end around the top of the bucket and close the top end by twisting and using a spring activated clothers peg. Such a sleeve will last two or three years before the nylon breaks down and you have to replace it. I have never used anything but Sphagnum Moss for the overwintering substrate. I wouldn't be happy using leaf mould, too many diseases and little pests in it. Better use some sterilised Peat and Sphagnum Moss from a garden centre. It's well worth the slight expense. Don't forget to put drainage holes in the bottom of the bucket. You must subject them to all the elements of winter weather. Don't hide them is some sheltered place in the hope of protecting them. They will invariably die of fungal infections. This method does work, I've tried many other ways in the past 50 years and none of the others have been successful.

Good luck.

Harry