The normal pattern of the fly out at the raven roost is for a steady stream of small groups, consisting of two or three birds to leave over an hour or so, with a few longish gaps and the odd larger group. This time, however, things were a little more spectacular, with most of the birds leaving in three large groups, interspersed with a few smaller parties. The first bird appeared at 04:15 and was quickly followed by a mass exodus that filled the sky with ravens. It lasted about five minutes and in that time 189 birds had been counted, but then there was a twenty minute gap until the next ravens appeared: a few small groups, then another sky full. So it went until the last couple of pairs, at 05:35, by which time the count had reached 426, which is comfortably the highest ever June count and only one short of the highest ever count for the roost.
It will be interesting to see if this trend continues through into the peak months of August and September.
By the time the count was coming to an end, the sky had been invaded by a thin cover of Cirrus and Cirrostratus, in which, with the sun still below the horizon, I spotted this bright, 'V' shaped patch in the sky, directly above the sun and connected to it by a very, very faint sun pillar, which isn't very visible in this photo.
The 'V' patch is called an Upper Tangent Arc and is usually attached to a 22 degree sun halo at the bottom end, but in this case, the halo hasn't formed. Tangent Arcs are formed when sunlight is refracted through columnar shaped, hexagonal ice needles falling in a horizontal position.