It was the best season since we've been keeping detailed records , with 490 sightings from 35 tetrads, the previous best being 390 sightings in 2010. As last year, it was a late starter. Although a single specimen had been seen on July 1st, no more sightings were made until July 8th, when the numbers slowly picked up. The peak was between July 14th and the 23rd, when double figures were seen, daily, in several woods, including 30 on each of two days, July 17th and July 23rd, in one wood. To put this into perspective, the previous best day in this wood was in 2010, when 16 were seen. Remarkably, in one very small wood [0.125 sq km, 12.5 hectares, 30 acres], 19 and 15 were seen on two separate days during the peak period.
The last was seen on August 21st, the latest observation ever in BBO, making it a longer season than usual, at 6 weeks.
Matthew and Neil have observed iris far outside woods on several occasions, and that has been our experience too, although most of these were in gardens not far from woods. Noteworthy was a sighting on the ground [with photographic evidence] of a male in a tree nursery, about 5km distant from the nearest wood where iris had been seen, in north Oxfordshire.
'Special' events: 1] For the first time in BBO, ab lugenda was seen. 2] On August 1st, 4 females were seen at sap in an Oak knothole in Rushbeds Wood, and this behaviour continued until August 6th. 3] In the very small wood mentioned above, a member observed 6 males pursuing a female high up in the Oaks.
All in all, a season to remember.