Sparrow time

I have noticed that the birds seem to have their own time for coming to the bird table. The blackbirds are usually early as is robin , the finches are there all day and the sparrows come about 5pm. Lots of sparrows come at once, usually at least a dozen these days. I watched one in particular today, It tried just poking a head through the bars and when that wasn't good enough it climbed up and inside. I have put a photo of just the head in as an extra. These are through the window, which I think I will have to clean as it could be better.