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JAC is named in loving memory of Professor Jenny Clack, a world-class palaeontologist, widely acknowledged as the leading authority on the evolution of land vertebrates from fish. The name JAC was chosen by Jenny's husband Rob who said "It seemed appropriate I should contribute to this important scientific study of cuckoos in memory of a top-class scientist, whom I adored."

JAC the Cuckoo
Tuesday, June 1, 2021 - 05:00
Tagging Location:
World's End, Llangollen, Denbighshire
Age when found:
Satellite Tag No.:
Wing Length (mm):

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JAC's journey from 01 June 2021 to 25 May 2022

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JAC's movements

29 Apr 2022 - JAC is back!

New updates that came in at around 6am this morning show that JAC has flown the remaining 582 km (362 miles) from France back to his breeding grounds in north Wales. The most recent update showed that he was within a mile of his tagging location. So if over the next few weeks you find yourself in the World's End area of Denbighshire, between Llangollen and Wrexham, be sure to listen out for the call of the Cuckoo, it might just be JAC!

19 Apr 2022 - JAC moves north in Spain

Llangollen Cuckoo JAC has flown a further 84 Km (53 miles) north and is now in the Sierras de Cazorla, Segura y Las Villas Natural Park in the province of Jaen in Spain. This is the largest protected area in Spain and is also a Special Protection Area for migratory birds.

13 Apr 2022 - JAC arrives in Spain

JAC didn't hang around for long in Morocco, by yesterday afternoon he was on the move again, crossing the Mediterranean. At 19:00 last night he was close to Berja in Andalusia, southern Spain. He pressed on and by 21:55 last night he was in the Sierra de Baza mountains approximately 20 Km south west of the city of Baza in Granada. 

11 Apr 2022 - JAC completes his desert crossing

After completing his crossing of the Sahara, JAC has spent the last 24 hours in northern Morocco. He is now approximately 15 km east of the city of Nador, hopefully enjoying some good feeding on the farmland close to the shores of the Mar Chica lagoon. 

10 Apr 2022 - JAC takes on the Sahara

Over the last few days Llangollen Cuckoo JAC has made his move north across the mighty Sahara. Since our last update he has flown 2,670 km (1,659 miles) north from Ivory Coast to his latest position in north western Algeria. At 21:00 last night he was still over the desert approaching the border between Algeria and Morocco. Light southerly winds in this area will hopefully help JAC safely on his way to northern Morocco or Algeria or even southern Europe where he can stop for a well-deserved rest. 

Past updates from Jac

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