Thank you, all - it was well worth the trip and the overnight stays to see the Swallowtails.
Wednesday 9th June was sunny from start to finish, cloudless and hotter than the previous day. I set out to have a look at one or two other spots where Swallowtails might be found, and headed initially for Hickling. I had visited this area once before, back in 2004, and it was remarkably unchanged. However, it proved quite difficult to track down the butterflies, but after a few circuits of the reserve I established which area seemed to be the hotspot. I realise in retrospect that it was the same spot where I had seen them 17 years ago - some things clearly don't change!
The heat and sunshine kept the butterflies very active, and despite seeing perhaps half a dozen I came away with just the one shot for the record.
I next explored How Hill. This site, despite having areas of suitable Swallowtail habitat close by, seems to be manage more as a general visitor attraction with a variety of areas on offer to wander through. Very pleasant and picturesque, but it somehow felt a little artificial, and despite an enjoyable stroll along the designated trail, I didn't come across any butterflies.
After this somewhat disappointing morning, I returned to Strumpshaw where despite the heat, I did have more luck finding Swallowtails. Today, though, they were to be seen out on the reserve...
...concentrated (as at Hickling) in one particular area and notably attracted to nectar on a number of guelder-rose trees.
There were a small cluster of enthusiasts in this area, one of whom turned out to be DaveO'B (of aberrant Duke fame). Good to meet you, Dave, and put another face to a name.
One of the butterflies took quite an interest in its gathered fan club, and repeatedly swooped along the path visiting each one of us in turn and threatening to land on one lady's hat in particular, and once settling briefly on some nettles.
It also posed from time to time on the reeds (or are those sedges?) out on the nearby bits of fen in typical textbook fashion...
...and on one occasion set off on a wild chase after a much larger individual of its own species (which the consensus decided may well have been a female).
Entertaining stuff. My last view of this magnificent insect was of it basking up in a sallow.
A full day, with a particularly good end to it - and a distinct contrast to the previous one in terms of butterfly behaviour.
Dave