RSPB Investigations Liaison Officer, Jenny Shelton, sheds more light on the disappearances of two hen harrier siblings, Marc and Manu, in similarly unsettling circumstances. Manu (left) and Marc (right) as nestlings (image by Tim Jones) If a mother hen harrier could give her chicks any words of wisdom, it might be this: stay away from grouse moors. Moorland is the natural habitat of these birds, but a number of them have disappeared over moorland areas managed for driven grouse shooting. The latest casualty is Marc, a bird who was satellite tagged in the Scottish Borders in 2017, along with his brother Manu, as part of the RSPB’s EU-funded Hen Harrier LIFE project. Marc’s tag had been functioning perfectly, showing him flying around hills and upland farmland all winter. Then, at the end of January 2018, he decided to explore a new area, moving 10km north west to a grouse moor near Middleton-in-Teesdale in the North Pennines. On 5 February, this is where his tag suddenly stopped transmitting, with no indication of any technical problems with the tag. If the bird had died naturally, we would expect to continue to receive transmissions from its tag, with the data signal showing the bird was stationary. We’d also expect to be able to recover the tag, as we have done with many of other birds like Mannin and Sirius , yet when investigations officers searched the area of Marc’s last transmission, they found no sign of the bird or his tag. Marc's last known location, with the circle indicating the area of his last known transmission What’s worse is that this has happened before and to Marc’s brother Manu, who were both named after a colleague’s grandchildren. The siblings grew up together in the Scottish borders, then fledged and went their separate ways, but both flying south into England: Marc settling near Durham and Manu in Northumberland. We’re devastated to see that the two brothers disappear in similar circumstances. In October 2017, Manu’s tag stopped transmitting over a grouse moor on the Northumberland/Cumbria border. After a search, neither his body nor his tag were found. As well as Marc and Manu, a number of other hen harriers have gone missing in similar circumstances both in England and Scotland since the Hen Harrier LIFE project began in 2014, most recently Calluna , who disappeared on a grouse moor in the Cairngorms National Park on 12 August 2017, coinciding with the first day of the grouse shooting season. Sadly, our hen harriers are facing a difficult future as the population continues to decline. In England, there were only three successful nests in 2017. This small English population could have really benefited from additions like Marc and Manu. Losing them less than a year after they hatched also means losing any young they and their potential partners may have had. Dr. Cathleen Thomas, Hen Harrier LIFE Project Manager, says: “It’s absolutely devastating to have both siblings disappear, one in Northumberland and one in Durham, particularly with the low number of hen harriers in England. Not only were we down to a tiny number of successful nests last year, but even those birds moving in to help bolster the population are vanishing. You can’t help but wonder, is there any hope for the English population, or will we be facing the very real prospect of their extinction as a breeding bird in England in 2018?” Tim Jones was the RSPB Investigations Officer who tagged Marc as a chick. “I got to visit my first hen harrier nest in 2017 and it was such a privilege to protect and monitor Marc and Manu's nest, seeing them when they were still white and fluffy at a week old to just before fledging when we fitted their tags. I’ve watched closely as they grew and spread their wings, checking on where they were and if they were ok every day for the last seven months. The loss of Manu was a real blow, and now knowing that Marc has disappeared too is completely gutting.” Currently there are fewer than half of 2017’s satellite tagged chicks still alive after six months. We really hope these birds stay safe: we’ll be keeping a close eye on our remaining hen harriers, and undertaking protection and monitoring of birds across northern England and Scotland.