Thank you, David - it's true to say that conditions seem to have made the more flighty species a bit more amenable this year. April often has days with periods of bright sunshine and cool easterly winds, which often keep the Brimstones and Orange Tips on the move.
This year, the sunshine we have had has only been in short spells, and often hazy too, even though temperatures have been higher than average. The mean daily maximum for the first half of the month local to me has been 16.5 degrees (the long-term average high for the whole of April here is 15 degrees - and the second half of the month would normally be noticeably warmer than the first half), but sunshine hours have been only 3.5 a day.
I would say that overall (going by numbers and variety), the weather has suited the butterflies. Bright overcast produces a fair amount of UV, now that we're past the equinox (as much now as it would in late August) and that seems to be a key factor in butterfly activity. The last few days have been particularly good as there have been high temperatures as well (19 on 11th, 21 on 12th, 21 on 13th, 15 on 14th).
None of this is any comfort to anyone further north and/or west where it has been duller, cooler and wetter...
Back to the butterflies themselves...
The forecast for
Sunday 14th April was for more sunshine, but quite a drop in temperature. Having heard from Bugboy that the first Duke had been seen down at Noar Hill, along with a suggestion that they might also have appeared on the Chilterns, I decided to head for Incombe Hole, not far from Ivinghoe Beacon.
Immediately having parked at the NT car park at Pitstone Hill, who should I see coming along the hillside from Tring Station, but Bugboy himself. Good to see you again, Paul, after the long break since the convivial gathering on that afternoon in late November.

There was indeed a bit of a keen breeze (it was still fairly early) but once the bottom of the "Hole" had been reached and the path that gently climbs along it, there was plenty of shelter and sunshine. We began looking for Green Hairstreaks, but for a while saw nothing but a Speckled Wood and a few Peacocks.

- The sun went in...
There were also Brimstone eggs on a buckthorn (but no Brimstones!).
However, we bumped into a fellow enthusiast who had seen one or two Hairstreaks, and before long they started to appear. I think we counted close to double figures in the end.
The morning wore on, and one or two more butterfly folk appeared, all hopeful of a Duke of Burgundy sighting. Bugboy and I were wandering back down the path and suddenly a small bright orange-and-brown insect darted past our legs at low level. It could only be one thing... In the relatively cool air, the Duke quickly settled on the ground to soak up some sun, and was easily approached. It was a bright fresh new male.
Hopefully, this will be the first of many in this area over the next six weeks or so. We were hopeful that there might also be a Grizzled Skipper or two around, but we didn't spot any today.
I decided to leave around one o'clock, remembering that it was the last day of the school holidays and I had the M25 to tackle: the traffic was indeed building nicely as I thankfully left it behind at J14. This did mean that after a bit of lunch I could squeeze in an hour on my local patch again...
A very successful and sociable first excursion of 2024 away from home!
Dave