Many feeders in the US have been graced with the presence of Common Redpolls by the dozens and even hundreds. I know one family who had up to 300 birds show up to their very attractive yard. I had a few days where there were over 100 on my feeders, trees and the ground below both. It was tough to even get a rough estimate because they would move around so fast and fly away at the smallest disturbance.
To get an idea of what my yard was like, here is a quick video that I shot through my window:
It took some time to get some great photos. I started by shooting from inside the house through my sliding glass doors. Quality remains pretty decent, but having window glass between L-series lens glass does degrade it a bit for larger sizes.
Shot through my sliding doors.
A great perch right outside my sliding doors.
One of my early photos on a snowy day shot through my sliding doors.
You have to be careful with flocks this large. I had one bird who would stick around after the flock left. I have a feeling that she was sick. I cleaned my feeders that night just in case.
Shot from the top deck right over her.
And finally I had a decent-sized flock on a sunny day. I slowly made my way onto my deck and snapped away at the birds from the far side so that I did not disturb them.
Shot from my deck.
Shot from my deck with some Christmas lights for size comparison.
Shot from my deck.
Whenever the large flocks would come, I would try to look for a more frosty bird in hopes of finding a Hoary Redpoll. It was tough to sift through them because they would move so fast. Finally, out of the corner of my eye I saw this almost white-looking bird on top of my pole system. My camera was already pointed at the feeders so I picked it up and snapped away. The photos came out much better than I expected!
I grabbed my camera as soon as I saw this more frosty Redpoll and snapped away. Within 5 seconds he was mixed in the flock never to be relocated again.