In the top Bucks wood yesterday afternoon, there was no sun, a very brisk breeze and a temperature of 20 degrees. Just 12 were seen in 66 minutes, all high up, clashing and gliding around the Oaks and Ashes. Little Sallow searching. When I retraced my steps along the ride where I had seen 6, about 30 minutes later, none were to be seen. I have seen this before: presumably, they are not constantly on the move and have periods of respite in the trees.
Today, the Campbells spent 140 minutes in the wood, in similar weather conditions as yesterday, and saw 43, so they have not peaked yet.
It is good to know that in woods where the numbers are high, we can go looking even if there is no sun; as long as the temperature is in the late teens, we will see activity.
A few days ago we were in Little Wood Oxon which is on a very steep slope. A very large wide Ash at the top of this slope is normally a banker for seeing activity; we saw nothing in 15 minutes. We went down the slope to the bottom where the trees are very close together, allowing poor views of the tree tops. In one small opening, however, we were treated to two pairs of males clashing.
Nothing is certain or predictable in the Emperor's world!