There have been no signals from Derek's tag since the end of August. Looking back at the data we received shows the battery charge was ok and there is no evidence of death. However, the most likely explanation for a sudden loss of signals is that Derek has sadly died.
Updates from our Cuckoos
Read the latest updates from our Cuckoos on their migration.
Concern for Derek
Derek crosses the desert
By the 16 August, signals show that Derek was on his way again, heading south over Algeria and making his desert crossing. The last signals on the 18 show he had made it as far as central Mali.
Derek is in Morocco!
Derek left Spain and arrived in Morocco, covering a distance of 800 kilometres (500 miles) passing east of the Gibraltar strait. Derek is taking once again taking the westerly route that we have seen him use in previous years and, interestingly, that only English Cuckoos seem to use. So far no Scottish or Welsh birds have ventured through Spain, although it's worth noting that fewer birds from these areas have been tagged compared to English Cuckoos. In some years, this route has proved problematic, with wild fires, droughts and storms providing challenges for the Cuckoos choosing this route.
Derek in Spain
Derek has continued on from France and is now further south, in the Castille and Leon region of Spain. He is currently the only one of our tagged Cuckoos in Spain, though Dudley passed this way earlier on his way south.
Derek on his way
A series of poor signals on the 5 July suggested Derek had crossed the Channel and was in northern France. Signals recieved during the early hours of 7 July confirmed that he had indeed left Britain. However, he wasn't in northern France. He is currently in southern France just north of Pau and close to the northern edge of the Pyrenees.
Derek still in the Broads
Derek is still in the Norfolk Broads, in the area that he arrived in on 26 April.Last year, he left on 22 July.
Derek back in Norfolk
By the morning of the 26 April Derek had returned to Norfolk and was back in the UK. From his postition in Spain he had travelled 1620km (1000 miles), crossing over France during the 24 April, to return his breeding grounds as the fifth of our tagged Cuckoos back to the UK.
Derek and Stanley north of Sierra Morena Mountains
From Morocco, Derek had continued on a further 1000km (600 miles) to reach Spain, settling in an area north of the Sienna Morena Mountains, by 15 April. He was joined here on the same day by Stanley, who had travelled north-west from his location near Granada and the Sierra Nevada Mountains. They are now only about 7km (4.5 miles) apart.
Derek crosses the desert
During the early hours of 13 April we received a location from Derek that showed him in Morocco, on the northern edge of the Sahara, the third of our tagged Cuckoos to successfully make it across.
Derek continues west
Derek's continued west and covered another 550km (340 miles) to reach his new location in Ivory Coast. He is about 60km (35 miles) north-east of Ash and 105km (65 miles) north of David's new location. All in all there are six Cuckoos in Ivory Coast currently.
Diversity in birding: why it matters
BTO's Jamey Redway reflects on diversity in birding, and how organisations like BTO play a role in making birding more inclusive.