Why Bother With Camo?

I called in on Fishers Green Nature Reserve on the way to M&S. Not much on the wing at Norman's Pond other than various bees, a few damsels and some gatekeepers.

It seemed really strange standing near the Bittern Hide and not hearing the gulls squabbling.

Swans and their cygnets homed in as I walked down the steps to the pontoon. The cygnets are huge now but still make a tiny cheeping noise.

Not so the grebelets. I went to one of my favourite vantage points and there was very little avian activity. I could hear an unmistakeable loud and constant whistling. As it came nearer I had my camera trained on where the birds would appear from behind the willows. Young grebes are so beautifully camouflaged with their zebra-striped heads blending beautifully with the water ripples catching the light. Why do they whistle so loudly?

I very seldom go for mono but thought this was a good opportunity as the only significant colour in the pic was the birds' red eyes.