Updates from our Cuckoos

David has moved west, leaving Central African Republic (CAR) behind and travelling 515km (320 miles) south-west to Cameroon. This is very similar timing to last year when he made the move from CAR to Cameroon on 13 March, before then moving to Mali by the end of March. Will he do the same again this year? 

David has left Lake Mai and travelled 380km (235 miles) north to an area close to the Congo River and just above the equator. 

There have been a few small movements recently. Fred and Jake have moved west into Congo whilst David has moved into the area that Emsworthy has left. 

These are likely down to changing rainfall conditions which may affect food availability and cause the Cuckoos to seek areas which may be more plentiful in resources. It will be especially important to find a good feeding area before they make any move northwards. There's no consistent direction in which these Cuckoos leave an area and one Cuckoo may move from an area only to be replaced by another moving in from elsewhere, with no obvious reason why.

On the 23 January we received transmissions from David's tag showing he had moved 200km (125 miles) north to Lake Mai, an area recently vacated by Emsworthy, who has travelled further north.  

Since arriving in the Democratic Republic of Congo, David has moved further south and is now on the southern edge of the rainforest. We last heard from in at 23.48 on 18 December.

David was still in Chad on 21 September but by the evening of the 23 September he had travelled 1085km (675 miles) south to the Congo rainforest in the Democratic Republic of Congo.

Six of the tracked cuckoos (Peter, Dudley, Emsworthy, David, Livingstone and Stanley) are already within the Congo rainforest block. The first of these to arrive was Stanley on 16 September, the earliest of the tracked cuckoos ever to arrive there by 12 days! He was followed by Emsworthy on 19 and Livingstone and Dudley on 23. Previous to this year, the earliest Cuckoo had been Chris, who arrived there on 25 September in 2012.

Since then, David arrived on 24 and Peter on 28 September 2014. David was five and four days earlier than in 2012 and 2013 respectively whilst Livingstone was 13 days earlier than last year. It is very interesting to note that all four of the cuckoos who beat the previous earliest arrival date came from northern Cameroon and the adjacent part of Chad, a region that has received over 50mm less rainfall than usual over the past month and more than 100mm less over the past three months.

With most cuckoos now in the Sahel region, we're entering a fairly quiet period in the annual cycle of the tagged cuckoos with less movement than during the migration season.

Birds who completed their desert crossing will spend time in the Sahel recovering their body condition, and some may stay quite a long time. In previous years, cuckoos have stayed in this area for as much as several months, while others spend a shorter amount of time before moving south into the humid zone forests.

The eastern Sahel in Chad and south Sudan has received plenty of rain recently, and thus conditions are likely good for cuckoos. Northern Cameroon was slightly drier than average in August, and so cuckoos such as Derek, Dudley, Stanley, and Emsworthy may be moving on if foraging conditions aren't suitable.

From Montenegro it appears that David then travelled down to Greece and made his crossing to Libya, Africa from here. Poor quality signals on the 4 August show him travelling through the Libyan desert and by the early hours of 9 August he had completed his crossing and made it safely to southern Chad. 

We are still following twenty-two birds. Currently two cuckoos are in France – Walpole and unnamed cuckoo 134957.

Five birds are in and around the Po Valley in northern Italy – BB, Chris, Stanley, Waller and Livingstone.

Six birds are in Spain – Two of these are big movers this week. After finally leaving the UK, Derek hasn’t hung around. After a brief stop in central-western France, he is now in central-northern Spain, just south of Tolbanos de Abajo. It is Maji that has provided the biggest surprise though. He seems to be taking a tour of the European mountain ranges. Having spent a time in the Austrian Alps, he is now in the central Pyrenees!

David is still in Montenegro and Ash is still in Croatia; both of these birds could make the move to Africa any day now.

We now have seven birds in Africa, six of them south of the Sahara. Emsworthy is the latest to arrive here and he is currently just south of Lake Chad, in an area that Chris also favours. Three other Cuckoos – Peter, Hennah and Dudley – are also close to Lake Chad.