Three more hen harriers disappear suddenly

Dr Cathleen Thomas, Hen Harrier LIFE Project Manager, reports on the sudden disappearances of three more tagged hen harriers in England and Wales in suspicious circumstances.

Just weeks after celebrating the breeding success of hen harriers in the UK this summer, the sobering reality of the continued illegal killing of our birds of prey was brought firmly into light with the suspicious disappearance of three satellite tagged birds in England and Wales.

All of the birds were fitted with satellite tags this summer as part of the RSPB’s EU-funded Hen Harrier LIFE project and we were regularly tracking their movements as they left their nests and started to make their way into the world. We’d hoped against hope that they’d at least manage to survive for a year or two, but we’re very sad to see that these three birds only lasted a couple of months.

Young female harrier Hilma was tagged in June 2018 at a nest on Forestry Commission Scotland-owned land in the Scottish Borders. After she left her nest, she moved across into Northumberland. Her tag was transmitting regularly when it suddenly and inexplicably stopped. Her last known fix on 8 August showed she was near Wooler, Northumberland over land managed for driven grouse shooting.

Hilma is the second tagged bird to disappear in Northumberland in the past year, after we reported on the disappearance of Manu in October 2017, closely followed by his brother Marc in Cumbria in February 2018.

Hilma. Photo - Steve Downing

A few weeks later another female bird, Octavia, vanished without trace. She hatched from a nest on National Trust’s High Peak Moors in the Peak District National Park in June. This was the first time the species had bred in this area for four years. Again, we had high hopes that the tables may have turned in favour of our hen harriers and we watched anxiously as she began to spread her wings.

Octavia stayed faithfully close to her nest, until the 22 August when she moved onto privately-owned driven grouse moors near Sheffield. Her tag was transmitting regularly when it suddenly and inexplicably stopped. Her last known fix on 26 August showed she was over an area of land managed for driven grouse shooting at Broomhead.

Octavia. Photo - Steve Downing

Just three days later, a bird in north Wales also disappeared. Heulwen was born on a nest in Gwynedd, North Wales, her name was chosen as it is Welsh for ‘sunny’. After she left her nest, Heulwen travelled through north Wales, across Snowdonia and eastwards towards Wrexham. Her satellite was transmitting regularly until it suddenly and inexplicably stopped. Her last known fix on 29 August show she was within the vicinity of Ruabon Mountain. Heulwen was not far from where Aalin, one of our 2016 cohort, went missing on 9 February 2018.

Heulwen. Photo - Guy Anderson

Satellite tagging technology is commonly used to follow the movements of birds and tags continue to transmit regularly, even if the bird dies. The tags were all providing regular updates on the birds’ locations, so the sudden and unexpected ending of transmissions from three birds all near grouse moors is suspicious, which is why the police are involved in all three cases.

For each of the birds, we have data on the location of their last transmission, which are shown in the maps below. We don’t know anything further about the movements of any of these birds after their last fixes. All three birds were searched for but were not recovered. It is expected that a bird that dies from natural causes the tag will continue to transmit data and provide the opportunity to be found on a follow up search.   

Last known fix of Hilma

Last known fix of Octavia

Last known fix of Heulwen

Hen harriers are one of the UK’s rarest birds of prey with only nine successful nests recorded in England in 2018 despite sufficient habitat for over 300 pairs. It is widely understood that the main reason for their low numbers is illegal killing associated with intensive management of driven grouse moors.

Just a few weeks ago we were celebrating the breeding success of hen harriers in the UK, but already these young chicks are disappearing in suspicious circumstances when they are just a few months old. It’s devastating for those of us involved in watching and protecting these chicks and terrible news for a birds of prey species that has shown a 24% decline in numbers between 2004 and 2016.

While we don’t yet know what has happened to these three birds, we do know that the main factor reducing the hen harrier population in the UK is illegal killing of birds associated with the intensive management of grouse moors.

If anyone has any information about the disappearance of any of these birds, please call the police on 101 – or if you have sensitive information which you want to discuss in confidence with the RSPB, you can use the Raptor Crime Hotline 0300 999 0101.