We can see summer coming from over 4,000 miles away as the first of BTO’s satellite-tracked Cuckoos begins to head north.
One of BTO’s tracked Cuckoos, known as PJ, was tagged in June 2016 in Suffolk and has since been providing BTO with key knowledge about Cuckoo migration. PJ has now begun to move north, travelling from Angola to Gabon on his way back to Britain, but this move is only a fraction of the journey that he will have to make.
Last year PJ returned to Suffolk on 29th April where he remained throughout his breeding season. On the 24th of June he began his migration to Africa for the winter, taking a more central route from the UK to his most southern point – Angola – avoiding the western route where we have seen more fatalities in other tracked Cuckoos.
PJ is one of only two BTO Cuckoos to have gone as far south as Angola; the information received from the tag identifying this as a new wintering location. In the last 20 years the number of Cuckoos in the UK has decreased by half. To find out why, BTO have been satellite tracking a number of Cuckoos since 2011. This year we are tracking eight different Cuckoos and following their migrations.
In 2009, the Cuckoo was added to the Red List of Birds of Conservation Concern. Although there was a lot of knowledge on the Cuckoo’s breeding behaviour while in the UK, little was known about their migratory behaviour. In order to get some insight into why there may be a drop in numbers of the UK’s Cuckoos BTO decided to use satellite tracking devices to understand their migration routes. We are using this information to find out what is causing the Cuckoo numbers to fall.