maybe that's when the temperature changes toward evening, or he can tell it's starting to get closer to sundown. who knows. but i TOTALLY beleive you. my animals know all kinds of crazy things and acknowledge things that i never thought they would have the brains or sensitivity to notice.

One of our auracana hens whistles to me when she wants me to pick her up, turn some dirt for her or give her some scratch. She's the only one that does it.

We too have a whistling rooster. It sounds like he takes one deep breathe and lets it out very slowly--yes it lasts a long time. And it does happen late in the afternoon. I was wondering about it too. I haven't noticed that the hens pay attention.

My Americaunas mix roo, Phoenix, does this. We tease him that he's sprung a leak. :) While he's doing it, he is standing still and alert, obviously he sees/hears/senses SOMETHING is wrong...the hens pay attention, too. No particular time of day for him, though.

Could be your roo has learned that around 4PM is the time the local hawks are out hunting for dinner.

Velvet ~:>