David wrote:- The first blackbird actually begins in the dark, the rest join in and off they go all day. We notice the blackbirds and thrushes do about 15 minutes each in the best places - then fly off to let the next booking start singing.
--- On Mon, 26/4/10, Brian <[email protected]> wrote: This morning I woke again to the dawn chorus, if its that good why don't they do it at a reasonable time of day like 7 am.? My reply:- As you'd expect there's been a lot of research on birdsong, and there are two explanations for the dawn chorus, which are not mutually exclusive; At dawn it's still too dark for birds to forage effectively, so singing is the best use of their time (given that song-birds normally only live a year, territory-holders need to confirm they are still alive - a rather grim experiment involved shooting the territory-holder every day and there was always some sap willing to step into his shoes for the next day!); Secondly, as the air is calm at dawn (and dusk) sound travels better so choosing that time means the message travels further. I've noticed in the garden that there has been vigorous chasing and fighting which has now calmed down as the territories have been established. As songs vary between individuals, adjacent territory-holders are so-called 'dear enemies' - in other words they listen for each other and know it's not worth re-running the fights. An unfamiliar song means drop everything and find the intruder. Hence the routine of going round singing where you're expected. [Non-text portions of this message have been removed]
