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Where do sooty terns go when they're not breeding on Ascension Island in the South Atlantic? The young can fly away for five years at a time before returning to start a family.

By using the very latest tracking technology the University of Birmingham has begun to answer that question. They attached tiny tracker chips about the size of a sugar cube to the legs of twenty sooty terns. These trackers can sense sunrise and sunset and that's enough information for the scientists to work out where the birds are.

So far the team has only recovered three of the trackers and they are sharing the data produced with us. As you can see the tracked birds spent up to 200 days out at sea travelling 25,000km. It's likely the birds spent almost all that time on the wing even sleeping while flying.

To keep the trackers as small as possible the data isn't transmitted back in real time. Instead the researchers have to find the birds they have tagged on their return to the Ascension Islands. It's a bit like looking for a needle in a very remote, smelly and noisy haystack.

This sort of technology is revolutionising our knowledge of all sorts of wildlife and the team from the University of Birmingham would like to buy more trackers to track more terns. Sadly the trackers are one-use only devices as they are tightly sealed to protect against the elements and being repeatedly dunked in the sea.

Trackers cost around £250 and if your school or wildlife group would be interested in helping this work and buying a tracker for the researchers to use then you can email the scientists in charge Dr Jim Reynolds at the University of Birmingham by clicking here.

None of this work would have been possible without the help and support of the Army Ornithological Society or AOS. You can read more about them . At the moment we can see where just three birds have gone but with more trackers the researchers can build up a comprehensive picture of the behaviour of sooty terns. Which will tell us more about the birds and about the wider health of the South Atlantic ocean.