What do you class as to foggy to bird

I got up yesterday and the fog did not seem that bad and I thought I would have a look for the Little Egret before work. When I got to Tir Founder Fields the fog was pretty bad and I could see a white bird in the distance but on looking closer it was the young Swan, I could hear a Kingfisher calling fairly close but I could not see the little so and so. Being one who hates to give up  I carried on around, I could hear Teal and found a single drake and a cormorant popped is head out of the river and boy did he jump but as hard has I tried I had no luck, there could have been 40 little Egrets and I would have still  missed them. Today I went there this evening and fed the swan but no sign of the Egret. As I was walking back out at about 4.45 pm, I looked in the drainage ditch on the right by the new house and there he was, was fishing and doing the old thing with his foot where they stamp and fish rush forward and it was nice to finish the  day on a high. I also had a late message from my daughter of her friends father last saturday who had a baby white heron when walking over to Adsa and looks like the Little Egret has been present longer than we think .

I also took this bad  record shoot just in case certain member thinks I am stringing and it's a white carrier bag and if I would pmsl .