Periodically there are synchronised national surveys for a number of raptor species in the UK, which help to build a picture of national and regional population trends. This year it was the national survey of breeding golden eagles, next year it will be hen harriers, and last year it was the peregrine.
The final results of the 2014 National Peregrine Survey are yet to be published – these things can take time, although we’d hope to see a publication in 2016. In the meantime, the project coordinator, Dr Mark Wilson (BTO Scotland) has written a short piece on the preliminary findings:
2014 National Peregrine Survey
The sixth UK breeding survey of Peregrine was carried out in 2014, providing a provisional estimate of 1480 pairs in the UK and Isle of Man. This initial figure indicates that the Peregrine population in the UK has remained largely stable since the last national survey in 2002. However, this overall stability belies marked variation in the trends of Peregrine populations in different parts of these survey areas over the past 12 years.
Peregrines are now distributed more widely and evenly than ever through the UK, due to decreases in Scotland, Wales and Isle of Man, and increases in England and Northern Ireland (see table). For the first time, the estimated number of breeding Peregrines in England is greater than that in Scotland, though these two countries still hold the majority of the UK’s Peregrines.
The country-level changes described above, together with regional trends in peregrine breeding numbers and territory occupancy, suggest that, broadly speaking, Peregrine numbers have decreased in upland areas, remaining stable or increasing in many lowland and coastal areas. The association of Peregrines with wild and remote places in the UK grows increasingly tenuous, as numbers nesting on traditional inland crags decline, and the numbers occupying lowland quarries and man-made structures continue to grow.
This ongoing redistribution of Peregrine numbers across Britain is probably being driven by multiple factors. Food supply is likely to be important; changes in numbers and availability of prey are likely to be having an effect in many areas. Illegal persecution continues to restrict numbers and productivity of breeding Peregrines in some regions, particularly where pigeon racing is practiced and where there is intensive management for red grouse shooting. In contrast, decreases in lowland persecution during the 20th century and the ban on organochlorines have had positive influences on numbers, and allowed Peregrines to expand into many areas where they were previously absent. But more work is needed, particularly on food supply and its role in limiting Peregrine numbers, in order to diagnose the cause of regional declines, and identify measures to halt or reverse them. [Mark Wilson, Research Ecologist, BTO Scotland].
So, not many surprises here. It’s been long-established that peregrines are routinely killed on many driven grouse moors but not so much in urban and coastal areas, where they’ve been doing well because, er, they generally aren’t poisoned, shot or trapped there, unless a dodgy pigeon racer happens to live nearby. These latest (preliminary) findings show it’s been business as usual on the grouse moors of northern England and Scotland.
The final sentence of Mark’s article is quite surprising though, and really should have been clarified. Food supply may be an issue for peregrines in some areas but it most definitely is not a limiting factor on driven grouse moors – those moors are heaving with red grouse! A brilliant paper written by Arjun Amar et al (2011 – we blogged about it here) showed pretty conclusively what was happening to peregrines on grouse moors in Northern England and it had absolutely nothing to do with lack of food and everything to do with illegal persecution.
Mark’s suggestion that ‘more research is needed to diagnose the cause of regional declines and identify measures to halt or reverse them’ may be true for some areas but not for areas that are managed as driven grouse moors. Extensive research, over many decades now, has shown exactly what the problem is and it’s high time it was addressed. Here’s the best way to address it – ban driven grouse shooting – please sign the petition here.
Tomorrow we’ll blog about another new paper, just published, that stemmed from the 2014 National Peregrine Survey. It’s about peregrine declines in North East Scotland, particularly in the Cairngorms National Park, and leaves no doubt that grouse moor management is central to the problem.
Peregrine photo by Steve Waterhouse