When satellite tagged hen harriers suddenly vanish, as has happened four times already this year with Chance, Highlander, Elwood, and Brian, the questions left unanswered are almost as painful as the disappearance itself. However, sometimes - just sometimes - a body is recovered and the mind can rest easy.
Hermione was one of four young to fledge from a nest on an estate owned and managed by the charity, Highland Renewal, on the Hebridean Isle of Mull in 2016. She was satellite-tagged by the Hen Harrier LIFE Project on 29th July 2016, and her name was chosen as the winner of an online poll run by the University of Central Lancashire (UCLan), who sponsored the tag.
Female hen harrier, Hermione, on the Isle of Mull, shortly after having her satellite tag fitted. (Image: Paul Haworth)
After fledging a few days later, Hermione spent all her time close to her nest area on Mull, with her tag sending out clear and consistent signals. On 28th September, however, it became clear from the data received that she had stopped moving. RSPB Scotland Investigations staff attended within a few days and quickly located her body and the transmitter, only a few kilometres from her nest – it was clear that she had died naturally, and her remains had been partially eaten. Sad though this is, many young harriers do not survive their first winter, with starvation or predation a regular cause of death.
It is interesting to contrast the death of Hermione with the disappearances of the four satellite tagged hen harriers mentioned above. The locating of Hermione’s body was straightforward, because, as we’d expect with birds dying of natural causes, her transmitter continued to provide us with good location data, directing our search efforts. In the cases of Highlander, Chance, Brian and Elwood, transmitters that were functioning similarly well, suddenly and unexpectedly stopped. While we will never definitively be able to say what happened to them without recovering their bodies, the weight of evidence is strongly suggestive of human interference and it is highly likely that these birds were killed, and the transmitters destroyed.
Arati Iyengar from UCLan offered this comment: "It is very sad to hear about Hermione’s death. However, there is some consolation in that her death was due to natural circumstances unlike in so many previous cases where human interference has been the most likely explanation."
Hermione's satellite data, along with that of all of our previously tagged hen harriers, will now be included in the Scottish Government review of satellite tracking data from golden eagles, hen harriers and red kites. We await their findings with interest.
In the meantime, we can only hope for a more positive future for our 9 remaining satellite-tagged hen harriers. Join us in following their fortunes on the Hen Harrier LIFE Project website at www.rspb.org.uk/henharrierlife or @RSPB_Skydancer.
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Hermione’s satellite tag was sponsored by the University of Central Lancashire (UCLan), whose researchers have recently developed a forensic DNA identification kit specific to hen harriers, which allows individual birds to be identified from tiny samples of genetic material such as blood or feathers. Find out more about this exciting research here.
Keith – thanks for your message.
Several birds of prey, fitted with satellite-transmitters, that have died, have been located in recent years. For example, I’m sure you will be aware of “Alma” & “Fearnan”, golden eagles both found poisoned on grouse moors in Angus, and “Annie”, a hen harrier found shot in SW Scotland. We have also recovered a number of birds that have died of natural causes – through predation or starvation, as well as transmitters that have become detached, as designed, from their hosts. It's also interesting to note that in the wader study you link to, despite three of the tagged chicks being predated, all three tags were recovered.
As you may have seen in our recent guest blog by the Dutch Montagu’s harrier project, the transmitters are highly reliable, and numerous recent studies, notably one on Black Kites in Spain, have demonstrated that, if fitted correctly, such transmitters do not adversely impact on the birds survival, breeding performance or behaviour.
With regards to your specific request to publish photos of Hermione, while we will of course notify the public through this blog if anything happens to one of our tagged birds (they are after all, public-facing already and one of the aims of the Hen Harrier LIFE Project is to tell their stories), we feel that while the Scottish Government review of satellite-tagged raptors is ongoing, it would be inappropriate to comment more widely on specific cases. We will be contributing comprehensive information regarding all of our dead or missing birds, including Hermione, to this review and await their findings with interest.