Cuckoo Tracking Project

Cuckoo. Alan McFadyen

Help us follow Cuckoos on migration and discover why they are in decline.

The Cuckoo is currently Red Listed as a Bird of Conservation Concern in the UK, due to its population decline.

Since 2011 we’ve been satellite-tracking Cuckoos to find out why they are declining. We’ve learned lots of vital information which could help us to understand our Cuckoos, such as how the different routes taken are linked to declines, and some of the pressures they face whilst on migration — but there is still more to discover. We now need to look more closely at how dependent they are on, and how much their migration is linked, to the drought-busting rains of the weather frontal system known as the Inter Tropical Convergence Zone (ITCZ) as they move out of the Congo rainforest and begin to head back to the UK via West Africa.

Follow our Cuckoos as they move to and from Africa.

This project wouldn't have been possible without the amazing support from funders and sponsors. Read more about the project and find out how you can get involved.

We have been able to share our expertise around tracking Cuckoos with other international studies, such as the Beijing Cuckoo Project.

Skill required

  • Follow our Cuckoos on the map below - use the controls to animate or step through their movements.

Cuckoo movements from 02 May 2021 to 22 June 2021

Cuckoo positions on
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Current Cuckoos

50042 the Cuckoo 50042 the Cuckoo


Status: active
AJ the Cuckoo AJ the Cuckoo


Status: active
Attenborough the Cuckoo Attenborough the Cuckoo


Status: active
Calypso the Cuckoo Calypso the Cuckoo


Status: active
Clive the Cuckoo Clive the Cuckoo


Status: active
Columbus the Cuckoo Columbus the Cuckoo


Status: active
Ellis the Cuckoo Ellis the Cuckoo


Status: active
Grove the Cuckoo Grove the Cuckoo


Status: active
Harry the Cuckoo Harry the Cuckoo


Status: active
JAC the Cuckoo JAC the Cuckoo


Status: active
Cuckoo 161318 portrait Cuckoo 161318 map marker


Status: active
Victor II the Cuckoo Victor II the Cuckoo

Victor II

Status: active

View previously tagged birds

Latest updates

Introducing AJ

18 Jun 2021

AJ was caught at the edge of RSPB Budby Common on the evening of 27th May. The team’s spirits were dampened a little when there was no response to the Cuckoo sound tape initially but after a while, a male and a female Cuckoo were heard approaching the nets. Soon after they checked the nets and found both birds in them! As night was approaching, they worked quickly to tag the male bird before darkness fell. As the team sat in the car under the forest canopy working under artificial light, a Tawny Owl called nearby, causing the Cuckoo to flinch markedly – a good reminder of the dangers these birds face throughout their lives. Since being tagged AJ has made the journey south across the Channel into northern France where he is approximately 80 km (50 miles) west of Paris.

Introducing Grove

18 Jun 2021

Grove was tagged in early June when we were getting to the end of the Cuckoo catching season. An early start was called for so we were on site at Wheatfen Nature Reserve in the Norfolk Broads by 3:30am. Nets were put up with the chorus of a reeling Grasshopper Warbler and a booming Bittern in the background, and we put the stuffed cuckoo out and played the sound lure. Two Cuckoos were immediately interested and started Cuckooing but did not come any closer for about 20 minutes. We were not entirely sure we were going to catch and another 20 minutes passed. Then the bird launched off its perch and flew towards the net, and we didn't see it come out the other side - these moments of "Is it in the net?" or "Is it just sat on a bush next to the net?" are agonising. The cuckooing sound had stopped which was a good sign. We looked at each other and edged gingerly towards the nets. As we got closer, we saw it in the net - time to run! 

Tagging the bird was very straightforward although this was the first time we have tagged a bird in a public toilet. The toilet was ideal - spacious and airy, and with all the facilities you could need. After tagging, we emerged into the car park where the bird flew off strongly. We were done by 05:45 and it was a real privilege as always to be up and about before anyone else in such an amazing place. A big thank you to Will Fitch, the warden of Wheatfen Nature Reserve, for allowing us to catch and tag a bird there.

Introducing Harry

17 Jun 2021

Harry was caught during the same session as Clive. Having seen a bird fly into the net, BTO tagger Lee Barber started running towards the net but the bird escaped, so he walked back to the car. Then the bird went in again, so Lee started running, got half way there but it got out again! The team decided to close their nets and as they were walking towards them a Cuckoo came flying straight in. The highs and lows of catching Cuckoos! Since being tagged Harry has remained at his breeding grounds in Worcestershire.

Browse updates from our Cuckoos

Project Lead
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Project timeline, contributions & findings

Project timeline

  • 5/11 - First round of five Cuckoos tagged, wintering sites in the Congo identified 
  • 3/12 - Different routes discovered on return journeys
  • 2016 - First scientific paper published on on the routes of our Cuckoos

Support the project

You can help keep this important project going by either giving a donation, becoming a Cuckoo sponsor, or gifting a sponsorship to someone else. We greatly appreciate the support the project has received, allowing us to continue to monitor this endangered species.

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