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Other ways to track birds
Using equipment to radio-track red kites
Colour coding
Ringing is not the only way to mark birds. Scientists sometimes use bright coloured dye on larger birds, such as geese. The colour stands out from a distance so, unlike ringing, there is no need to catch the bird again to check where it has come from. The dye does not harm the birds, but the colour usually disappears when they moult their feathers.
Angels
Migrating birds also show up on radar. During World War Two, British forces looking for enemy aircraft noticed unexplained patterns on their radar screens, which they called ‘angels’. These turned out to be flocks of small birds crossing the English Channel. Today radar can even detect individual birds. It can even work out, from the pattern of wing beats, roughly what size they are.
Remote control
Scientists can now follow migrating birds by attaching lightweight electronic transmitters to them and tracing the signals. At first they used radio transmitters, but these stopped working when the batteries ran out. Today they use solar-powered satellite transmitters, which last much longer. The signals are beamed back to scientists via satellites in space, and allow them to track every twist and turn of a bird’s journey. A signal was once even picked up from a dead brent goose hanging in the freezer of the hunter who had shot it! Have a look at some of these journeys using the links on this page.
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