A lot of interest is shown at the moment in the decline of the house sparrow (Passer domesticus). The seed feeders in my garden are regularly attended by 30-40 sparrows at a time with the coming of the juveniles in early June. Evidence:
Notice the green plastic mesh around the feeders to stop the feral pigeons getting at the seed. They still scavenge around the perimeter but only in 3's or 4's not the flocks of 20+ that were taking a lot of the gleanings as well as hanging on the feeders themselves and taking seed directly.