Barnes - Birdwatching With Your Eyes Closed: an introduction to birdsong

B irds sing. Each species sings a different song. Thats quite interesting for the human being who happens to be listening, but its life and death for the bird. When a bird sings, it sings the song of itself. The first and most basic piece of information that the song conveys is which species the bird belongs to. There is no point in a blackbird singing a lovesong to a wren: a young man might just as well present a bunch of flowers to an orang-utan. It is important for a blackbird that a blackbird sounds like a blackbird.

A willow warbler looks almost exactly the same as a chiffchaff. As a general rule, a chiffchaff will have darker legs, but thats hard to see at a distance, for both a bird and a human, and besides, its not one hundred per cent reliable. If you happen to be a bird-ringer and you catch a willow warbler in a mist-net, you should be able to tell it from a chiffchaff because the willow warblers wings are proportionately longer; a willow warbler flies to Africa for the winter, while a chiffchaff only goes as far as southern Europe, so the willow warbler needs better wings. But a willow warbler is not going to catch another willow warbler in a mist-net, nor is it going to measure its wings with a pair of callipers. So it sings.

The songs of these identical-looking birds are radically different, as we will see when we take a closer listen to both birds later. You dont need to see the bird. A birdwatcher need not watch a willow warbler or a chiffchaff. You only need to listen. If you are a birdlistener you can tell instantly, and with your eyes closed. Willow warblers and chiffchaffs are birdlisteners: so will you be, if you wish.

We humans are different from most mammals. Most mammals have a highly developed sense of smell. For a dog, a lamp-post is a thrilling thing. To a human, a well-sprayed lamp-post is merely mildly disgusting, and a dogs fascination mildly amusing or mildly irritating. But to a dog, it is The Times hot off the presses; latest news, social column, gossip. He reads it through his nose and learns which dog passed by when. Then, as if joining an internet chatroom , he will add his own contribution by means of a cocked leg. If you study mammals, you come to understand that an awful lot of the most important matters of their lives are based around urination and defecation: middens, the spraying and scattering of dung. It is impossible for humans to empathise with this: we just dont have the equipment. Our noses are pretty coarse and feeble instruments. We smell in black and white, while a dog smells in eternal rainbows of subtle and delicate nuances. But birds are not great smellers, on the whole. Some vultures use smell to locate carrion; albatrosses can find feeding fish by smell; nightjars and swifts have a reliable sense of smell. But smell is not all and everything to any birds, as it is for a dog. They have other ways of communicating. As a dog pisses, a bird sings.

And a birds song does something that a pile of dung can never do: it touches a human heart. I have established the presence of otters in front of my house, not, alas, because I have seen their sinuous selves, nor because I have heard their sweet song. No: instead of singing, otters will leave a spraint in a prominent place. Under a bridge is a favourite. A spraint is an otter turd. I rejoice to find a spraint: coiled and fish-stinky under the bridges arch: but I am not moved by the spraint itself, only by what the spraint means. A spraint touches an otters heart, but not mine. Like birds, we humans are creatures of sight and sound. Birds bring colour to our eyes: but the brightest and most brilliant thing they possess they bring to us by means of their voices. And like the birds themselves, we humans are touched and moved by birdsong.

Learning birdsong is not just a way to become a better bird-spotter. It is tuning in: a way of hearing the soundtrack of the planet earth.