Showing posts with label Emperor moth caterpillars. Show all posts
Showing posts with label Emperor moth caterpillars. Show all posts

Tuesday, March 07, 2017

Somebody keeps putting topsoil on my allotment...

...the plot thickens!

Here's the scenario: 3rd March 2017 I was sitting quietly in my studio today, just reading-up on bloody-nosed beetles. I had seen a Flickr photo posted by my friend Tim, and was intrigued as to why they are common where he lives in Jersey, and yet, I have not found any locally. It was a faint, fluttering noise that distracted me. I stopped and listened; it seemed to be coming from the corner just under my window. 
   Once I had removed all of the gumpf that was obstructing my view, I could just make out movement between the end of the worktop and the wall; the gap is tiny. Using the back end of a plastic scalpel handle (the only thing to hand that fitted), I tentatively worked my way along the gap. As I reached the far end of the worktop, out popped a very tatty looking, but rather large moth.



   It doesn't take the world's best expert in identifying moths (which is handy, 'cos I am far from that) to know right away that this is a male emperor moth. No problem identifying the moth, but would it be so simple to work out where it came from and what it was doing there? Probably: it is surely obvious? I have a number of emperor moth pupae/cocoons that are over-wintering, and like the hawk-moth I recently blogged about, one must have emerged early.



   All I needed to do was examine each cocoon carefully to see which one was no longer intact. A job made somewhat easier by knowing that the larger ones were likely to be female; as my moth is male, I only need check the smaller ones. And so one-by-one, I gave them the third degree. Having scrutinised all but one, I knew, because I am sharp as a new pin with these things, it must be the final one! Nope...that one was intact too. Eh? I must have missed something? I probed them all one more time with the same result, all intact. 

   Well now...
Assuming this isn't an unexplained apparition (can you have an explainable apparition?) there has to be a rationale. Think JJ...think! Er...erm...




   Awe...ah! Jeez, I....maybe...no wait!  I had emperor moth larvae once before and I kept them in here, in my studio. I remember that I had raised them almost through to pupation and had read that they pupate on their food-plant. Reassured that they would indeed build a cocoon on the bramble they had been feeding on, I left the lid off their house one night and come morning, there was no sight of any of them. Despite a frantic search, I didn't ever locate a single caterpillar.

One of the original caterpillars

   I assumed that they must have found their way outside and into the garden. I put it down as a learning experience and determined to do better if I ever had another chance. Could it possibly be that one of the original larvae did manage to build a cocoon and it remained here undetected? Is there a faint chance that this moth emerged from that cocoon?

   Well I do know, have heard of these insects remaining as a cocoon through two winters, and even read of a case where one didn't emerge for three...but four? Is that a possibility? I would like to think so, and frankly, what other explanation could there possibly be? I have contacted a couple of people who know far more than I about moths, to see if either of them can give me a definitive answer. I'll let you know how that pans out.



And that's where you might expect this fable to end. But no...




   The two days weren't quite as annoying as that flashing image, but I had another nasty head cold, so they were fairly tiresome. Anyhow, back to the narrative; you know how it goes...'I was sitting quietly in my studio today, when I heard a faint, fluttering noise that disturbed me'. Surely not? It couldn't be, could it?

Well slap my ass and call me Samantha! As they say...don't they? Oh! Okay then, stone the crows, I'll be a monkey's uncle! This time it was emanating from t'other end of the building. It didn't take long to discover that it was indeed a second moth. Another male emperor, and this one seemed to be newly eclosed as it looked perfect. What a beauty it is too; I have seen some fabulous moths in my time but this one...


Now I know that this is part camouflage, and part defence in terms of design and colour but man! Mother Nature sure excelled when she devised this one. 


Forsaking any further developments, this means that 2 of the original larva must have survived in here for close on 4 years then eclosed. I have not heard of anything like this before, but can't think of a possible alternative. Unless you know better? 


Saturday, July 02, 2016

Hans Christian Andersen comes to mind...

Since my last update (yes I know it was ages ago now) I have been lucky enough to have a number of Emperor moth caterpillars (Saturnia pavonia) to look after and observe. This spectacular moth is fairly common over much of Britain. I had a few of these once before, but managed to allow them to escape at pupation time. They wandered off into the garden somewhere, never to be seen again. 

This time around I ensured they were secure and got them through to pupation in quite large numbers. The emperor caterpillar overwinters as a pupa and should emerge in April or May the following year, although I have read they can sometimes take 2 years. I am hoping for a mixture of male and female as they are both impressive looking moths.

Not much to add and so I will just let the pictures do the talking. You will see just how much they change as they continue to moult, and how varied they can be. It is in fact the very reason caterpillars can be tricky to identify, changing with each moult as they do.


May 14th

I was convinced this one was drinking the water...





May 20th

Freshly moulted for the first time...



May 21st

Part moulted...






May 23rd 






May 25th





May 28th









May 29th




May 31st







June 5th














June 6th





June 8th





June 9th









June 10th













June 14th





Final instar and moult...




June 16th





June 18th







June 25th





       




       




       




Early stage cocoon.




A completed cocoon.