Blog Post: The decline of the hen harrier in NE Scotland

By Ian Thomson, Head of Investigations, RSPB Scotland There is no denying that the hen harrier is one of our most spectacular and enigmatic birds of prey. It breeds in remote, out-of-the-way locations, often in the uplands, miles away from the biggest centres of human population. For me, it’s a bird that never fails to lift my spirits, one that always brightens a day out birding or hill-walking. I’ve been lucky. I was brought up in Aberdeen, and as a teenager going through my birding formative years in the late 1970’s and early 80’s, was fortunate to be there at a time when the North-east Scotland Raptor Study Group (NERSG) was in the process of being created. The hills and glens of Deeside became a second home to me for several springs, with the chance of seeing golden eagles, merlins and peregrines. But, the monitoring of breeding hen harriers was always one of the highlights. My dominant memory of those days was being invited along one day to help with ringing the chicks at three nests in one of the glens that went off to the south of the main Dee valley. I’d never been to a harrier nest before, and could barely contain my excitement! I’d watched the adults on several occasions from a mile or so away, so the opportunity to see these birds up close was brilliant. But, at every nest, there were no chicks. There were no adult birds around. There were cold, dead eggs. “They’ve been done.” said one of my colleagues. At that time, I suppose, on reflection, I’d little concept of what that really meant. But fast-forward 35 years, and I now lead the RSPB Investigations team in Scotland, I know exactly what it meant, and days like that are why I do this job. A paper that I’m sure will be of great interest to many, but is particularly so to me personally, has just been published in the journal British Birds .“The past, current and potential status of breeding Hen Harriers in North-east Scotland” [1] is a testament to the incredible efforts of a number of people in the NERSG in monitoring the fortunes of this species over the last 35 years. Several of the authors had been undertaking harrier monitoring before my first forays into the Aberdeenshire hills, and they continue to do so. It is however a depressing story that this paper tells. A peak population of 28 pairs in the area in the early 1990’s had declined to only one confirmed breeding pair by 2014.  Year after year, raptor workers carry out hundreds of hours of unpaid fieldwork, driven on solely by their commitment to the conservation of their chosen species. And every year, raptor nests fail and adult birds disappear. It’s widely acknowledged that bad weather, food shortage and predation are factors in breeding attempts being unsuccessful. But we also all know that places like the moors of north-east Scotland, the southern uplands around the Borders, and the Peak District of northern England are areas where food for harriers is abundant. These are also the areas where we’re told that upland breeding waders are thriving because of the intensive predator control regimes undertaken by sporting estates. So, if there’s plenty of available food, abundant nesting habitat, very low numbers of predators and other ground-nesting species like waders (and grouse!) are doing well, why are hen harriers doing so badly in these areas? The answer is pretty simple – persecution. What proof is there of this? There have been very few proven recent cases of illegal killing of hen harriers...  This is indeed true. But when you have a very small population, you’re not likely to get many proven cases of persecution. The damage has already been done. Raptor populations cannot withstand a level of attrition where year after year, adults are killed or nests destroyed. Suffice to say that in 2013, when the population of hen harriers in NE Scotland, as listed in this study, was only four confirmed pairs, by sheer luck, birds were witnessed being shot at two nest sites. In both cases, the perpetrators removed the dead harrier. That’s no surprise as why would a criminal want to leave evidence of their crime lying around to be found?  But, many birds are being killed out of sight of witnesses? Population studies such as this give you a good idea. From 2004 to 2010, the population of hen harriers in Scotland fell by 22% to 525 pairs. In 2011, the Joint Nature Conservation Committee published “A conservation framework for hen harriers” [2] . The conclusions of this piece of work were that the potential hen harrier population of Scotland was estimated to be within the range 1467–1790 pairs, but that there was strong evidence that, in the uplands of eastern and southern Scotland, illegal persecution was causing the failure of the majority of breeding attempts, leading to fewer breeding birds and/or fewer successful nests. It was depressingly predictable that certain organisations that claim to represent land management interests dismissed the conclusions of this report, in part by claiming the findings were out of date. The good news for them is that the Hen Harrier framework has been revised, and is due for publication, hopefully very soon. I wonder if this revised version will elicit different conclusions?  Or will this latest piece of work, monitoring and documenting the hen harrier population of NE Scotland be similarly disputed by those who are part of the denial culture that seemingly pervades much of the game bird shooting industry? But, I have news for those that seek to undermine the efforts of those who are out in all weathers monitoring Scotland’s birds of prey, and bringing the decline of these magnificent birds to the public’s attention. This report’s findings are the reality. I know. I’ve been there.   [1] Rebecca, G., Cosnette, B., Craib, J., Duncan, A., Etheridge, B., Francis, I., Hardey, J., Pout, A., and Steele, L. (2016) The past, current and potential status of breeding Hen Harriersin North-east Scotland. British Birds 109: 77– 95 [2] Fielding, A., Haworth, P., Whitfield, P., McLeod, D. & Riley, H. (2011) A Conservation Framework for Hen Harriers in the United Kingdom. JNCC Report 441. Joint Nature Conservation Committee, Peterborough.