Excellent shots and especially in not ideal conditions. The duck looks darn good, focus is about as god as you will get. The Heron is a great BIF and also love that natural setting you have there, nice greens to show this off on. You've been getting some great shots and as said in another thread, be stubborn with it and these results show you are anywayNice work from that lens IMO. 70-300, not bad at all.
All the best very nicely done. Keep them coming.
Danny.