Posted 23rd May 2018 by Peter Byrne
The disappearance of three protected and satellite-tagged hen harriers in Scotland and Cumbria has prompted the police and RSPB to appeal for information
Saorsa, a hen harrier who had been monitored since fledging in June, suddenly stopped sending transmissions in February 2018 whilst located in the Angus Glens, Scotland. Since then, she has not been seen or heard of.
There were also concerns over a male bird named Blue in March this year, when his tag suddenly stopped functioning and inexplicably cut out near Longsleddale, South Lanarkshire.
The same month, a tagged bird named Finn vanished near Moffar, Scotland. The bird was tagged as a chick in 2016 from a Northumberland nest, and as one of only three hen harrier nests to fledge young in England last year.
When tagged hen harriers have died of natural causes in the past, both the tags and bodies are generally recovered, yet this time, RSPB Investigations staff found no signs of tags or bodies.
Part of the EU-funded Hen Harrier LIFE project has seen several birds fitted with a lightweight satellite tag, to help to build a better understanding of hen harriers, their movements, and the threats that they face. Since 2014 (when the project started), a number of tagged hen harriers have disappeared in similar circumstances.
Cathleen Thomas, Hen Harrier LIFE Project Manager, said: "The UK population of hen harriers is really hanging in the balance and the disappearance of these three birds is extremely troubling. These tags are over 90% reliable and capable of transmitting long after a bird has died. If these birds had died of natural causes we would expect to recover both the tag and the body. But this has not been the case."
Image courtesy of Andy Hay / RSPB Images