Now you have had the 60-600mm sigmonster lens longer, what are your thoughts on its performance? There is little on the web, and it does have an intriguing focal length range.This one seems to be Red-winged Blackbird. But I have never seen any with this feather pattern and this angry!
EOS-R with Sigma 60-600mm, @600mm, f/6.3, ISO1000.
Beautiful shots, I look forward to their return every year. It is really hard to tell the difference at this stage, but if you see him singing that's a give aways.