I went to Poor's Field in Ruislip Woods. I looked around for a while without seeing much though there were a lot of Jays with acorns and a lot of Wrens alarm calling. A Nuthatch called and a Greenfinch flew over. This wasn't really the quality of birding I was expecting, and I was about to go back when a distant Siskin call distracted me and made me stay a bit longer.
As I looked up to the sky I saw a flock of birds drop down to a tree nearby. They looked like finches, but very big ones. I immediately guessed they were Hawfinches, but I could not see any colour as the sun was against them. They soon flew to another tree, this time more distantly, then didn't show again. When they were in flight I saw some colour on them, confirming their ID. I managed to get a few photos, but none of them clear.