Thanks David. It's normal - as you will have gathered following my posts in previous years! See statistics below ...
Hi Philip. As it happens, I am currently finishing a fairly lavish (physical) guide to the butterflies of my own region, Villars-Gryon, which I hope the Tourist Office will sell from next spring. I will investigate the possibility of publishing it in some protected electronic form too (Kindle &c.). It includes an appendix covering the rest of Switzerland in less detail (but all species). As to Wurzel, thanks for buying the original app. I am sorry we haven't been able to update it with new pictures, information and coding for the latest iOS.
Yesterday I went in search of cardinals at a different site, where I saw a single male in the spring and where another was reported last year. I had noted a suitable patch of Buddleia on a suitable road and sat some distance away, under the shade of a bridge, for about an hour:
As that picture implies, the weather was rather cloudy, with sunny intervals, but it was warm and fritillaries were flying. Just not cardinals. I was able to photograph things with the superzoom, despite being 20-30m from any Buddleia. Silver-washed were the commonest fritillary, enjoying a certain peace they would never have had if a cardinal had zoomed through:
There were also high brown, niobe, heath and Queen of Spain. Rock graylings were everywhere, not just on the Buddleia ...
... but on my beer too:
That one then sat down near the beer, preventing me drinking it for about 20 minutes:
It did at least give me the opportunity to get decent photos of it:
Twice, a large tortoiseshell came and sunbathed on the rocks in the foreground in my first picture above:
Interesting to see one so battle-worn in August. It must go into hibernation and save itself for the important battles in the spring!
Seeing no cardinals there, nor anywhere else on my walk yesterday, I conclude there is not a thriving colony of cardinals here! My original colony remains THE colony.
My walk took me up to higher meadows. Lots of August Satyrids were flying, including ...
... great sooty satyr ...
![Image](http://www.guypadfield.com/images2017/ferula3aug2017a.jpg)
(that female is absolutely typical for this region, with very strong forewing spotting)
... large wall ...
... Scotch argus ...
... and lots more rock graylings. I tried to string some into woodland graylings, which I am sure flies in the region, but didn't have my net and didn't get anything conclusive.
This is the normal Swiss form of male spotted fritillary, very common yesterday:
For comparison, here is Sagarra's lesser spotted fritillary, that I photographed for the first time in Spain a couple of weeks ago. You can see that it is rather similar to spotted, but those crescent-shaped lunules and the more straw, tawny ground colour do make it look noticeably different.
Finally for yesterday, here is a marbled white with a rather weary Zygaenid -
fausta, I think:
Back to today. More losses: Spike and Glory are nowhere to be seen. This doesn't necessarily mean they are dead, but it is probable. The hard reality is that if a female purple emperor lays, say, 300 eggs, 298 of them must die before reproducing if the population is to be stable. That is a probability of 0.993 of dying. If you find, say, 10 eggs, the probability of ANY of them reaching reproductive adulthood is 1 - (0.993^10) = 0.068. That is, there is roughly a 93% probability
none of them will survive. Including dead eggs, that is how many I have found so far this summer - 10. It would be irrational to expect any of them to reach reproductive adulthood.
More statistics. If you assume, for argument's sake, an equal probability of dying on any day of the year, these numbers correspond to a half-life of 1 month 20 days (300 down to 2 is 7.2 half-lives - that is, 2 x 2^7.2 = about 300; 12 months divided by 7.2 = about 1 month 20 days). That means, if you find 10 eggs, 5 should still be living after 1 month 20 days. I have lost more than this in a little over a week. This implies a greatly increased mortality at the beginning of life. This strikes me as natural for two main reasons. Firstly, any important genetic irregularities leading to intrinsic weaklings might be expected to be filtered out rather quickly. It's tough from the beginning - those that survive the beginning are the fit ones. Secondly, conditioning of predators in searching for a particular stage is likely to be more efficient when that particular stage is more numerous. If a good number of leaves have a little larva sitting at the end of them, a clever tit might quickly learn to look at the end of leaves. Or, a clever forest bug might stay in the same tree, working its way over every leaf. By June, when there might be only a handful left in the whole wood, finding them is going to be much more random. In addition to these reasons, many insectivorous birds are currently fattening themselves up for migration (but not the tits, of course).
I'm happy to say, though, that Angel and Dawn are doing fine. Here is Angel - still 1st instar:
Those symmetrical cuts into the leaf make searching for established 1st or 2nd instar larvae easier. The mobile larvae, that don't really establish themselves, are much harder to find.
Dawn is currently mobile! As I arrived at her leaf today she was on the move:
She then turned left onto a small leaf:
I could see that the tip of this leaf was brown and suspected that she would reject it when she got there. On the contrary - she stopped at the beginning of the brown, then began silking it up (swinging her head from side to side along the parts she wants to stick to):
When I left her tree, some ten minutes later, after searching for more cats or eggs, she was still at that leaf tip:
It will be interesting to see if she chooses to stay there.
Guy