Adonis aberrants

[Susie]

Did you go on the walk? If so, how was it?

[Gibster]

Did you go on the walk? If so, how was it?

Yes. Cloudy and windy.

Actually it wasn't too bad, but the Adonis were keeping very low thanks to the less-than-ideal conditions. The aberrant individuals caused no small amount of interest, but no earth-shattering ideas as to why they were so apparent this year. I pretended to know what I was talking about, and probably got it all wrong, but at least I didn't roll head first and out of control down the slope as one lady did!!!

Cheers,

Gibster.

[FISHiEE]

Could the exceptional heat in April have had an effect during the development stage on those in ant hills more exposed to the sun/heat and those more sheltered that didn't get so hot developed normally. And those same 'hot' individuals also had trouble emerging, due again to the heat/dryness where they were and resulted in the aberants all being damaged? However I wouldn't have thought the heat to be exceptional in comparison to on the continent at the time of their emergence there, and this doesn't happen there.

Also, another theory regarding the damage, could be that we had 2 nights on the trot of torrential rain/thunderstorms in late April that maybe coincided with their emergence, and the damage could be associated with that?

[Gibster]

However I wouldn't have thought the heat to be exceptional in comparison to on the continent at the time of their emergence there, and this doesn't happen there.

Hi FISHiEE,

I'm certainly not going to spout a load of scientific blurb at you, mainly because I don't have much of an idea myself!

But on the continent Adonis Blues (and other species such as Heath Frits, for example) occur in more diverse habitats than they do in southern England. As I understand it (I need Guy or Felix to step in here!) the species is at the limit of it's cold weather tolerance levels in England, so only occurs on the warmest south-facing slopes which are natural heat traps. Same with the Heath Frits (sheltered, bare clearings in warm woodlands - the most suitable microhabitat for them to thrive in, which is why the Kent colonies were in such a terribly trapped situation when coppicing all but died out in that region). So if these south-facing slopes are already creating a very warm micro-climate, exceptionally hot weather when the ground flora is still impoverished will "super-heat" the slope and create the aberrants in the first rather than second generation.

Or something like that? Sounds plausible to me. Not sure where I stand on the cold weather theory. Maybe the double combo is to blame?

Cheers,

Gibster

[Pete Eeles]

Here are some thoughts from Ken Wilmott (FRES):

Dear Peter,

I have spent another couple of days at Denbies Hillside, investigating the astounding number of aberrants, mostly minus underside spotting (ab. krodeli), before replying to your email. During the many years I have spent with the Denbies Hillside colonies (I live 10 minutes drive away in Leatherhead) I have certainly never found them so easy to find. There sometimes seems to be fewer 'normals' !

I agree with Matthew's suggestion that impacted, dried out soils are the probable cause of crippled Adonis Blues, and I have also found that sometimes females are mated by males before they have successfully dried their wings. In my eighteen years of living in Leatherhead, this year (I keep weather records (rainfall, temperature especially)) I recorded my highest April temperature of 78 degrees fahrenheit and it was probably a little warmer on the south facing slopes of the North Downs that day. It was amidst a period of four days when temperatures were 75f + in succession. Just when many Adonis Blues were pupating !.

I have only found one pupa in the wild (photographed on colour transparency) and it was within an earthen chamber (photo) which with the top carefully removed and three Myrmica ants were within (photo).

Many butterfly aberrations can be created in captivity (as they probably are in wild situations) by either cold or heat shock in pre-Pupa, Pupal stage. If the krodeli aberration is one such then perhaps the pupa in its earthen cell was in a particularly hot spot and more exposed than others, particularly as there has been less grass growth (light shade?) this spring due to the extreme drought conditions. This may explain the krodeli cripples as they struggled to emerge from their over-cooked earthen cells.

However, my work during the past two days has been most interesting as I have found three assymetrical aberrations. One, krodeli on one side, the other side nearly normal. Despite the almost impossible I was able to take two photographs of the RH side and then LH side whilst it was at rest on the same flowerhead ! Don't know how I would have proved it otherwise (not being a butterfly collector !). That was yesterday, today even more intriguing. I found another assymetrical aberration, normal on one side, krodeli on the other. The krodeli side was crippled, the 'normal' side was perfect !! Perhaps the Pupa was skewed sidewards in its earthen cell so that only one side was aberrant, but that does not explain why the Adonis Blue escaped from its baked earthen cell without its normal side showing some indication of the struggle. Interestingly, despite being crippled to some extent she was still busily egglaying.

The third assymetrical aberration was a female upperside, with one side of the forewings having red lunules on the leading edge near the chequered fringes and rayed blue streaks on the hindwings, whilst the other side lacked the red and blue rays. Photographs were taken (with some difficulty!) of these three assymetrical aberrants.

On looking through my colour transparency collection I found krodeli photographs taken in 1983 (a great year), 1988, 1997 (another year of abundance) and 1999.

It certainly seems to be linked to climatic factors. The second brood 2010 showed this very clearly, with a large emergence of females (at least 12+ couples in cop. on a short walk) as the August cool and damp gave way in early September to a short warm spell. Out they came !

Rainfall for March here in Leatherhead 12.00 mm., April 5.5 mm, and so far in May 11.5 mm.

Cheers,

- Pete

[Susie]

I am extremely interested in these aberrations (butterfly aberrations have piqued my interest anyway since last year's SWFs) and as far as I can gather (in layman's terms) a possible theory is that these adonis developed too quickly due the uncommon spring heat and basically emerged not fully baked. The scale colouring process in particular being a stage which was rushed through or upset due to the unusual circumstances. I think added to this was the dessication of the pupa which caused damaged when the butterfly tried to emerge and you end up with a variety of aberrant and/or damaged butterflies.

I understand that ab. krodeli are not terribly uncommon at Denbies anyway but perhaps that is not genetic and purely down to the way the site is situated and how it catches the heat.

Edit: Oops, Pete's post beat me to it!

[Pete Eeles]

Edit: Oops, Pete's post beat me to it!

Not really - I think everyone's coming to the same conclusion. The linking of ab. krodeli and deformity has the same root cause - a baked pupal chamber!

Cheers,

- Pete

[Susie]

Righty ho.

[Pete Eeles]

As you've all probably gathered - this phenomenon has been pointed out to the great and good

A response from Jeremy Thomas (published with permission):

"In my limited experience of finding Adonis pupae in the wild, all occur in ant cells, and cripples are likely to result from attempting to emerge from baked soil, possibly exacerbated by hungry ants which get xenophobic in times of drought and extreme stress, often attacking and eating the resources they normally protect under more benign conditions. Abbs are indeed likely to result from the elevated temperature. It wouldn't surprise me if the cells near the surface hit the high 30s (C) at times during the hot dry spell when there was little vegetation to shade them. This begs the question as to why we don't see more abbs near the southern range limits of Adonis (or other species); a not-wholly-satisfactory answer is that they are almost certainly different physiological races further south (it would be interesting to do some constant temperature rearing experiments on that), and/or that they are occupying cooler niches (less southerly aspects, taller vegetation) under warmer climates, which we know to be the case.".

I thought the ecological connection with ant behaviour was a superb addition to Ken's observations. You read it here first

Cheers,

- Pete

[FISHiEE]

It's all very fascinating stuff, and a real educational experience for me and many others too I suspect.

If it is, as believed, a temperature related issue, then if the conditions are 'normal' for the second brood on this site, we can expect there to be no aberrations in the 2nd brood. But some abberations are genetic, and can pass on from generation to generation (referring to Pete's talk on genetics and aberrations of a few months back at a Hampshire branch meeting).

It also indicates that different 'exceptional' conditions can result in different aberration forms of the same species? A 'hot' Adonis, a 'cold' Adonis etc. I don't however want to stumble upon a 'windy' one!

[Susie]

Could ab. krodeli be better suited to hot dry conditions where the fauna is parched?

[Gibster]

You mean Florb, as the man in the ad used to say...

[Susie]

whoops, yep, I meant flora.

[MikeOxon]

I've been looking at all these aberrants and am now wondering about some old photos of my own.

I've had these labelled as Common Blues but perhaps they're Adonis? They were photographed at Lough Down in September 1998 and there were Adonis flying at the time. Anyone like to offer any thoughts?

Mike

[Susie]

How about, "WOW!"

[FISHiEE]

I'd say common blue from the lack of any black markings on the wing edges... but then that could be part of the abberation I guess!

Pretty impressive whatever they are though!

[Piers]

It's a common blue for certain (I say "it's" as it looks to be the same individual in both images).

[MikeOxon]

Many thanks, Piers. It is just one individual - when I wrote 'they', I meant photos not butterflies - wasn't very clear!
I'm glad to know that it hasn't been wrongly labelled on my website!
Mike

[Piers]

I should have added, Mike, that it's a stunning and rare find - well done you...

[MikeOxon]

Thanks for your comment, Piers. It sent me back into my archives and I found that I took 12 photos of this butterfly, including some topsides, which I had completely forgotten. I must have been impressed, as clicks cost money in those film days! You have prompted me to scan the originals at higher quality, and I have posted some images on the Common Blue aberrants gallery - but I'm now 'off-topic' here.
Mike