A challenging autumn migration - 04 Sep 2019

The last few weeks have been quiet and for those who had not yet completed their desert crossings, it looks like the challenging conditions have claimed more of our tagged Cuckoos.

Unfortunately no further signals have been received from Knepp. From the temperature data and movements at the time, he was alive on 12 July, when we last heard from his tag. Though the battery charge had been low for a few days, there is no evidence of long term battery decline so we can't be sure what has happened to him - either he, or the tag, appear to have died suddenly. 

Lambert, who was still in France, has not moved on south and signals on 21 August showed high temperature fluctuations across the day, indicating the bird's body temperature and behaviour were not regulating it. We've heard nothing since then, and his tags battery charge had suddenly dipped, all of which leads us to believe he has likely died.

Unfortunately the challenging conditions have also impacted on Nussey who has already attempted two trips to Africa and retreated to Europe.  Abnormally low temperatures were received at the time of the last messages (16 August), having previously been fine. He was not migrating at that time, so the low temperatures were not due to high altitude, and the battery was also much lower than previously, further suggesting he was dead.

The droughts and exceptionally high temperatures in Europe appear to have proved difficult for our Cuckoos this year, however the five south of the Sahara are still regularly transmitting. Valentine, PJ, Carlton II and Tennysons' tags have all sent signals during September and the last signals received from Senan's tag were at the end of August and show him still in Burkina Faso.

Concern growing for Knepp - 13 Aug 2019

There have been no further signals from Knepp since 12 July when the battery in his tag was functioning well. Given that there is no evidence that his battery was failing, his sudden disappearance just a day after arrival at his last known position means we are now seriously concerned that we won't hear anything more from Knepp. 

Knepp crosses into Spain - 18 Jul 2019

Knepp is now 595 km (370 miles) south west of his last location in south west France and is just 1.5 km (1 mile) south of the shore of the Valparaíso Reservoir in the province of Zamora, Castile and León, Spain. He is very close to the village of Villardeciervos. Knepp also stopped in this area last year but was 26 km (16 miles) south west of here, nearer the town of Trabazos, where he stayed until July 28 before crossing into Morocco. 

Knepp pushes south - 12 Jul 2019
Having flown 382 km (237 miles) south west from his last location south of Paris, Knepp is now near Mirambeau in the Nouvelle-Aquitaine region in southwestern France.
Knepp is on his way - 19 Jun 2019
During the evening of 14 June we received a series of locations from Knepp's tag that showed he was in Picardy, northern France. By the early hours of 15 June he had moved a further 152km (94 miles) south. He is currently just over 50km (35 miles) southwest of Paris and just to the east of the town of Vierville. He is the first of our tagged Cuckoos to leave the UK this year.

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