Derren Fox and Kirsty Nutt describe the seabird breeding season success at both Fowlsheugh and Troup Head and why Scotland's seabirds are still struggling.
On a day like this, summer feels a long time ago... but it’s nice to think back to those long, bright days when a walk along cliffs in Aberdeenshire was filled with the sounds of calling seabirds. From the kittiwakes repeatedly calling their own names to the strange laughing arrrs of guillemots.
Two of Aberdeenshire’s seabird colonies are also RSPB Scotland nature reserves – this reserve Fowlsheugh and Troup Head near Pennan, which is also home to Scotland’s only mainland gannet colony.
Each year we monitor how the seabirds that breed on the cliffs are doing by making accurate counts and observations in specific sections of the cliffs or ‘plots’. The changes in these counts give us an index of how the birds are faring from one year to the next.
We had some good news from our plot counts this year. The number of nesting kittiwakes at Troup Head’s plots was up from 395 last year to 414 and these pairs produced 460 young. Kittiwakes at Fowlsheugh had a great breeding year too with 394 pairs in the plots there producing 545 chicks - a record!
Longer-term trends
2015 saw all the reserve staff out counting seabirds Fowlsheugh and Troup Head. This is because every three years we count every single bird on these two huge colonies, and, as you can imagine, it’s a challenging job! This year between us we counted over 100,000 birds and nests! After several weeks of counting, checking and recounting we have some final figures to share with you and the news is encouraging for some species.
The spectacular cliffs at Fowlsheugh (Derren Fox)
There appears to be some good news for both guillemots and razorbills this year, with numbers at Fowlsheugh up significantly on the last count back in 2012: guillemot numbers (recorded as individuals rather than nests) increased from 44,922 in 2012 to 55,507 in 2015. Over the same period, the number of razorbills (the second most numerous of the auk species here) went from 5,260 to 7,426.
Kittiwake numbers had a very slight increase too, with numbers of AONs (Apparently Occupied Nests) going from 9,439 to 9,655. This may not seem like much of an increase, but following on from a massive local and national decline and poor productivity (the number of chicks raised each year) this is still encouraging.
Kittiwake by Grahame Madge (rspb-images.com)
We’ve got even more comforting news about Fowlsheugh’s kittiwakes. Our productivity studies this year – we follow a number of nests through the breeding period and seeing how many chicks each nest fledges – have shown they had a brilliant year!
From the nine study plots scattered through the colony, we found that on average productivity was 1.38 chicks per nest, which is the best we’ve had here since we started collecting data on productivity in 1993!
They aren’t out of the woods yet, and numbers wise they’ve got a long way to go to get anywhere near the numbers in the early 1990s, but it’s certainly nice to have some better news to spread about our kittiwakes.
Seabird numbers at Fowlsheugh (1992-2015)
Kittiwakes and gannets at Troup Head (Kirsty Nutt)
Up at Troup Head on the north coast, there has been a similar story with the auks, with guillemot numbers increasing from 14,030 in 2011 to 20,539 this year and razorbill numbers going from 1256 to 2147. Fulmar numbers are also up a little on the last count.
But, it’s not all good news I’m afraid from Troup, with kittiwake numbers declining again, down to 7,180 AONs from 7,961 in 2011.
Seabird numbers at Troup Head (1969-2015)
The rest of Scotland
In 2015, other RSPB Scotland nature reserves recorded increases in seabird numbers and lots of healthy seabird chicks fledging their nests, despite the exceptionally wet summer we had. On Tiree, guillemot numbers increased from 2,068 in 2014 to 2,634 individuals this year, while at Fidra in the Firth of Forth, there were 1,026 active puffin burrows, up from around only 800 in 2009.
The figures are a welcome reprieve from the chronic declines seen across Scotland in recent years, but don’t pop the champagne cork just yet.
These short-term increases are often coming after a period of phenomenally fast decline, like with Fowlsheugh's kittiwakes. And seabirds in Shetland and Orkney continue to struggle. Only 570 kittiwake pairs were recorded this year at Marwick Head on Orkney – a decline of 90 per cent since 1999, when the site held 5,573 pairs. Guillemot numbers at Marwick Head also dropped from 34,679 to 8,645 over the same period. Devastatingly, this year saw kittiwakes being lost entirely from North Hill in Orkney. The bottom line is that across Scotland, since 2000, we’ve lost two thirds of our kittiwakes, Arctic skuas and Arctic terns.
What’s gone wrong?
We don't have all the answers – the marine environment is complex – but we are beginning to understand the subtle connections of the marine food chain and how they can be unravelled. Warming seas creates changes in the plankton (the bottom of the food chain) which results in fewer sandeels which are an important food for chicks. Fewer sandeels means fewer chicks survive and if this is repeated year after year, it plays a big role in the devastating declines we have witnessed.
What can we do?
Scotland has already designated more Marine Protected Areas than any other part of the British Isles, but the Scottish Government could help do more. They have already identified 14 potential Special Protection Areas, which are internationally important parts of our sea; unfortunately, they are dragging their feet when it comes to designating them.
You can find out more about the problems facing seabirds and how you can help safeguard sealife at rspb.org.uk/joinandhelp/donations/campaigns/sealife/