c.30 Chiffchaffs in the combined areas of the Yeovil Sewage Works and Yeovil CP (Riverside Walk) this afternoon. Also 8 Goldcrest and one Firecrest.

Cheers Adam - really interesting. Unlike you, there were few other species involved in Crewkerne - just a handful of Goldcrests (which were not especially associating with the chiffs) and some Blackbirds and Chaffinches down on the filter beds. There were two Grey Wags amongst the dozen or so Pieds. But the chiffs themselves were spectacular and possibly more concentrated than yours. When they all dropped down en masse onto the beds from the surrounding trees, it was like watching leaves falling and swirling.

I too noticed the effect of position/light conditions on the variability of the Chiffchaffs. When they were down on the filter bed, they all looked like tristis: the green and yellow hues just disappeared. But when they were up in the trees and bushes, the yellows were much more obvious. When the (probably) real tristis showed up, however, it did stand out… I just was never able to study it for more than a second or two. I’ll hopefully get down there again tomorrow.

Ken

I had a very similiar experience on my local patch this morning. Very interesting to read your account. I havn’t been on patch for weeks (area on outskirts of Yeovil, between the water treatment works at Flushing Meadow up to the new development at Wyndham Park). Today I decided to go ‘off piste’ a bit and explore a new area near the perimeter of the treatment works. It was crawling with Chiffchaffs. Just standing still for a while made it clear how many were feeding on the floor, along the riverbank/margins and more in the lower/understorey. It was quite a spectacle, alongside good numbers of Goldcrest. Despite my best efforts I found it very hard to count the number of birds, and was conscious of double counting due to nature of the various feeding parties, but given the ground I covered and the different areas the birds were feeding I too estimated a minimum of at least 50 Chiffchaffs. It felt like every other bird was a Chiff! Wish I had discovered this for the end of Sept/Oct period.

Interesting to see the amount of variation between the Chiff’s, and effect of different light conditions, but couldnt find a stand out tristis/fulvescens type, certainly no stand out calls either. Not to say I didnt overlook any, and I’m sure someone with more experience may well do better. Surprised I couldnt tease out a Firecrest either, surely there is one in there somewhere! Grey Wagtails looking lovely, and a female Reed Bunting was welcome sight.

I see Tim Farr had at least 10 Chiffs at a much smaller site just over the border in Sherborne yesterday.

Last weekend I observed about a dozen Chiffchaff at Crewkerne Sewage Works. I suspected there were more, but didn’t have time to linger. Today, I returned to take a better look.

The birds were difficult to observe and when I first arrived there didn’t appear to be any. I soon heard one but did not see any for about 10 minutes. Then a small number appeared in the trees near to the filter beds on the north side and dropped onto the beds. Before I knew it more and more birds were dropping down and in one sweep across the bed I got to 38. Other birds were still present in the bushes and it was also apparent that many birds were out of sight below the near rim of the bed. There were certainly at least 50 birds present and potentially many more. I was pleased with this count but checking the recent ‘Somerset Birds 2016’ report it would appear that this is quite an unusually high number (e.g. “...sewage treatment works were less covered; counts for these came only from Evercreech, Crewkerne and Pudleigh, which held 14 between them.”)

At times the whole flock seemed to make off together and move through the surrounding vegetation for up to about 15 minutes at a time. Even when present they were skittish and difficult to observe probably because of the presence of a hunting Sparrowhawk.

There was at least one probable Siberian Chiffchaff which lacked yellow tones, being a cold brown and off-white with relatively clean flanks and a strong pale supercilium… but I would like a better look.