This weekend... listen to the sunrise symphony

This Sunday is International Dawn Chorus Day, an annual celebration of the beauty of birdsong. To mark the occasion we’re running lots of special guided dawn chorus events at our reserves up and down the country.

To get the full effect you’ll need to set your alarm alarmingly early, but the chance to experience one of the marvels of nature really shouldn’t be missed!

In fact, the astonishing complexity, beauty and power of birdsong has inspired poets, writers and composers throughout history, but our enjoyment is incidental to its real purpose.

So, why do birds sing?

Love songs and battle cries

Birds have become Nature’s master musicians in order to convey to potential mates, rivals and predators all the important things they have to say – from “Keep out!” to “Pick me!”.

Keep out!

Holding a good territory, with lots of potential nest sites and an abundant food supply, is really important for a male bird - so once he’s found one he won’t give it up easily! This is where his song comes in – by belting out a really loud, powerful song he’s staking his claim on the area and sending out a clear message to other males in the vicinity to “Keep out!”.

Birds can even distinguish strangers from neighbours by subtle differences in their songs. This means that the male can focus his defence efforts on genuine intruders, rather than wasting his energy hassling the chap living next door.

Pick me!

Before they commit, females need to know a little bit about their prospective partner and a male’s song is one way that he can advertise his credentials.

If a male can produce a long, loud, complex song after a night without food, this tells females that he must be an excellent forager living in a really productive territory - in other words, excellent dad material!

Why sing in spring?

The increase in daylight as spring approaches sets male hormones racing, and this triggers breeding activity - so the dawn chorus begins.

Most males will keep on singing throughout the breeding season, until their annual moult in late summer forces them to keep quiet – after all, the last thing you want to do when your feathers are falling out and you aren’t quite as quick off your perch is to advertise yourself to predators! 

But why do they sing so intensely at dawn?

   Sunrise symphony

   Not only is the air generally calmer at dawn,
   making sound transmission easier, there’s
   not a lot else to do!
  
   Light is poor and the cool temperatures
   keep insect prey from flying, so foraging
   is tricky.

   What’s more, if males haven’t been able to
   forage successfully during the previous day,
   they may not have sufficient energy reserves
   to last the night, so dawn is a time when males can announce their survival, both to rivals and potential mates.

Females also lay their eggs at dawn, and are at their most fertile immediately afterwards – making it imperative for a territory-holding male to deter rivals and secure the female for himself.

Go on, just this once...

Listening to the dawn chorus truly is an unforgettable experience, so go on, set that alarm clock and immerse yourself in the uplifting sound of birdsong this weekend.