Silver studded blues

[Susie]

Has a number of aberrants/cripples been recorded in the silver studded blue population this year in the same way as the adonis have been affected?

[GOLDENORFE]

just got back from prees heath, only saw about 60 , all in perfect condition!

[Susie]

I went to iping today and saw quite a few deformed butterflies. I am not sure how much variation there is in pattern but there quite a few small males that didnt look quite right as well.

[FISHiEE]

I've visited Iping and Steadham commons quite a few times since end of May and can't say I've noticed anything untoward with the butterflies there. There are some small ones, but nothing more than normal variation in size I'd say.

If there were lots of deformed butterflies there Monday, perhaps some foolishly tried emerging in the rain the site had all day sunday and sunday night? Certainly on Sunday morning I didn't see any butterflies with issues and I walked just about all of the site. There were a few feresh looking butterflies, but a lot are a little past their best now. Probably not helped by rain the past few days.

[Susie]

I went back today and didn't find a single one. I wonder if it was due to the poor weather over the weekend.

I met Robin Crane today (very nice person!) and mentioned to him my findings yesterday. He said that he hadn't seen anything like it in 20 years. Thanks to this forum I was able to call up my photographs and show him what I meant.

He's a couple of photos from yesterday (there are more in my diary).

How small do they usually get? There were one mating pair today where the male was smaller than the female and she wasn't any bigger than average which is smaller enough to start off with!

[FISHiEE]

Very odd... definitely some kind of issue when pumping up the wings... or do they pump them up one at a time and they just haven't finished yet? Might explain why they were all fine today...

Good to hear there's plenty of fresh ones emerging. I might get another crack at the ants Had one go, but it was all over very quickly and the most anty butterflies were right in the thick of the heather. Needs to be quite warm though I think for them to emerge making it difficult in a pre-work dawn raid when I have to be left by 7:20. Might have a go tomorrow tho!

[Susie]

Well whatever it was it appears to be to be the same problem many of the Adonis had at Denbies this year. Butterflies pump their wings up simultaneously. If it had just been the one I might have thought it was something restricting the butterfly on one side as it's wings were inflated but there were quite a few around, all in one area, which points (in my mind) to there being something wrong with the butterfly as it emerged which was probably caused during pupation.

I found a snap I took yesterday of a mating pair where the male was very small, he is about a third smaller than the female (she was normal size but looking at the pic I can see she has some deformation or damage to her wings too), so I wonder if there was a lack of food around for the caterpillars again due to the hot weather.

Let me know how your early morning lightning strike gets on.

[P.J.Underwood]

I am terribly sorry to raise this again,but I now have information from a reliable learned source,that experiments have been done in the past to produce abberants.Essentially, the pupae are subjected to low temperatures of the kind we saw this winter.Taking the temperature down produces various degrees of abberation,until the pupa is killed and does not emerge.This critical temperature will vary with each species.That is how some of the Artic species can survive-their body contains better antifreeze!
P.J.U.

[Piers]

Hi P.J.

It has long been known to amateur 'aurelians' that extremes of temperature during the late larval/early pupal stages of certain families of butterflies can produce extreme aberrations. Some aberrations are specific to either heat or cold shock and some (such as ab. nigrina in the white admiral (an all-black aberration without the usual white markings)) have been produced in captivity by subjecting the developing pupa to either condition.

Other abnormal environments (such as an atmosphere excessively rich in oxygen, or the absence of light during the larval stages) also have peculiar (but predictable) effects upon the pigmentation of the adult butterfly.

While you are right to consider excessive cold in playing a part in the appearance of aberrant butterflies in the wild, the temperatures that were experienced in this country during the winter would have been at the wrong stage in the life cycle to have had this sort of effect upon the silver studded and adonis blues (ova and early larval stages respectively).

Books such as Variation in British Butterflies by Alec Harmer have some very interesting plates of the results of such extremes of temperature produced in captivity by entomologists such as Karl Bailey and others. Back issues of periodicals including the Bulletin of the Amateur Entomologist's Society and The Entomologist's Record have many articles upon the causes of butterfly aberration as well as detailed write-ups of experiments on the effects of extremes of temperature etc. upon the early stages of butterflies that have been conducted in captivity over the years.

Piers.

[P.J.Underwood]

Thanks Piers,it sounds good scientific stuff to me.I do wonder what the effect of extreme cold ,-26 degrees, could have had on eggs in January.There is also the length of time they were subjected to these extreme temps.I will read the publications you mentioned.
P.J.U.

[FISHiEE]

I think the males and females can both vary in size by quite a bit. If you see blues roosted up together early or late in the day this can be quite clear. The males at Iping do seem to have a bigger size range than the females that's for sure, and there seem to be more smaller males ones in the last few days. Possibly to do with food availability/temperature during the later laval stages that wasn't such an issue for the eralier larvae that emerged first?

The females are generally a bit smaller than the males, but a large female paired up with a small male would have the female bigger than the male. There's several about at the moment bigger than the smallest of the males.

Definitely there's several more emerged since Sunday morning. No sign of any emerging before I had to leave for work this morning despite it being 15c at 5am thanks to a couldy night.

[Susie]

Thanks, Fishee, all interesting stuff. The female in my photo was, to my eye anyway, usual size and not exceptionally large but the male was tiny. However he was a very strong flying and had no trouble flying off with her attached so he obviously had something going for him.

[millerd]

I visited Fairmile Common near Cobham in Surrey yesterday. There were plenty of SSB about, mostly past their best, but with one or two fresh individuals. All were within normal size range, all females were smaller than the smallest male, and none appeared deformed.

The best of the bunch below.

Dave

[Susie]

Gorgeous photo, Dave.

I think I must have a knack of attracting oddities!

[millerd]

Thank you Susie!

Luck as always - a point, shoot and run moment as I had a child-collection deadline and was into the margins of safety by then!

You certainly have seen more than your fair share of the unusual this year.

Dave

[Susie]

You certainly have seen more than your fair share of the unusual this year.

Dave

And last year, in fact ever since I discovered that butterflies were supposed to look a particular way I've found ones that don't.

[Trev Sawyer]

...

[Trev Sawyer]

You certainly have seen more than your fair share of the unusual this year.

Dave

Yes Susie...
You met Jack Harrison a few weeks ago

Only joking Jack

Jack... Jack... Get away from me with that tripod!

Ouch!!

Ooh, that's going to be a real "shiner"

That's better.

Trev