The British Trust for Ornithology is tracking the migration routes of five British cuckoos, in an attempt to find out what environments the birds rely on and where they feed on route. Miniature satellite-tracking devices were fitted to the birds like backpacks this June. Having set off from a breeding ground in East Anglia, they have now reached Africa and are now distributed across 3,000km of the continent.
During flight the trackers turned on for ten hours every two days, sending off a radio signal to a satellite, which identified their location. The BTO’s Dr. Chris Hewson was able to track the birds from the trust’s headquarters in Thetford and is still keeping check on the birds.
Four of the cuckoos have now crossed the Sahara, which is a major souce of mortality for the birds. Two are said to be in southern Chad, one is in northern Nigeria and the fourth is in Burkina Faso. One cuckoo has fallen behind but made it as far as Morocco.
The British cuckoo population has slumped since 1995, losing about two thirds of its cuckoos in the last 25 years. This study will help the trust understand the bird’s migration patterns and possibly even work out where they are dying.