Seabirds Count A Census of Breeding Seabirds in Britain and Ireland (2015–2021)

There are many aspects of our birdlife that we should take great care of, but I would argue that our seabird populations are the most important by far, both nationally and internationally. Not only are these birds important, they are also relatively well-studied, although with 25 species to keep tabs on it is a major undertaking. Thus, in addition to any ad hoc studies, the government has a major monitoring programme and this book is the culmination of intensive surveys between 2015 and 2021.

Each of the 25 species gets a chapter, which provides both an introduction to the bird and its ecology and also the methods used to census it. The results of both this survey and others carried out before are tabulated and discussed. Two colour maps indicate the breeding trends, both by size of colony (mapped precisely) and the latest trends since 2000 shown by each 25 km square. The total numbers nationally (and by local areas) are tabulated and also displayed on a pie chart. Comparisons against other countries in the North Atlantic are also given. These chapters are liberally illustrated by excellent photographs of the birds and their habitats, and these are accompanied by a set of colour paintings by Robert Vaughan.

So, what did the survey find? Surprisingly, perhaps, the total number of breeding seabirds has remained almost unchanged since the last survey, in 1998–2002, but there were major changes in the make-up of species. Thanks to great conservation initiatives, there have been increases in some of our rarer species, such as Roseate Tern (up 15%) and the Mediterranean Gull, which increased 16-fold! Some commoner species, however, have shown steep declines. These were particularly marked in Scotland, where 15 species have declined, compared with reductions in only seven species each in England, Wales and Northern Ireland. Bizarrely, several species of gull, tern and auk have seriously declined in Scotland but have increased in Ireland, so clearly population changes are operating differently throughout the UK.

But what is causing the changes? The authors are clear that food availability is the main factor, with climate change and competition with fisheries being major influences. Seabirds are also suffering from the effects of predators, both directly on themselves and also through competition for food supplies. Severe weather events are increasing in frequency and can affect the overwinter survival of both adults and juveniles. There are many other factors at play – such as the closure of landfill sites that provided easy pickings for gulls – and these are discussed in a lengthy chapter. There is also an overall assessment of how important our seabird populations are internationally, offering a useful reminder that we provide nesting areas for most of the world’s Manx Shearwaters, Northern Gannets and Great Skuas.

It is abundantly clear that, in the face of ever-increasing pressures on the marine environment, surveys such as this are essential if we are to understand and react to population changes. Tragically, as the survey period closed in 2021 the status of many seabirds started to be affected by the arrival of avian influenza. It remains to be seen just how severe the effects will be. Thankfully, some seabirds are already showing signs that they may be developing immunity to the virus, but not before many thousands have died from it.

This is the latest in a series of atlases publishing the results of censusing breeding seabirds around Britain and Ireland. As with its predecessors, it is a technical work. However, seabirds have a large following of enthusiasts and this book has an audience beyond scientists, conservationists and policymakers. The involvement of a commercial natural history publisher like Lynx Nature Books has helped to elevate the book to a finely produced natural history book with good design elements giving it a clean look with well-designed tables and maps. The choice of font size is good for a comfortable read and evocative illustrations by artist Robert Vaughan and a selection of excellent images all help to uplift the book. With the shape of a large field guide (height 24.5 cm × width 16.5 cm) and at 528 pages it is a hefty book. It will become an essential reference for any future work monitoring seabirds in the region.

As with the previous atlases, it is the outcome of a vast collaborative exercise. The page opposite the title page carries the logos of 31 organisations which are categorised as lead partners, partners or additional funders. This provides the first inkling of what a massive project this has been. More on the hundreds of people involved in the project are covered in the Acknowledgements and Introduction. We also learn in the introduction that over 1,000 volunteers and professionals gathered data from almost 10,000 sites and more than 5,500 urban 1 km squares. Having helped with the publishing side of both a bird atlas and a butterfly atlas for the London Natural History Society, I also find it interesting to understand the people effort behind publications.

The book comprises a few major structural parts. The Methods and analysis (pages 15-40), Species accounts (pages 41-426), Rare breeding seabirds (pages 427-433), International importance (pages 435- 438), Causes of seabird population change (pages 439-466) followed by Appendices (pages 467-484) and References (pages 485-526). The methods and analysis section is necessary for a serious user of the information to understand what is being presented but may also be useful reading for people involved in similar fieldwork. In this book, an important unit is the AON or Apparently Occupied Nest. The species accounts are beautifully presented opening with artwork at the top followed by standard headings for Introduction, Census methods and coverage, Status and trends, Discussion and International context. Each of the species accounts has the species authors identified. There are tables, charts and maps. The maps are of a good size occupying the whole page with symbols of a good size as well. It only takes a glance to see the difference in distribution between coastal nesters such as Fulmar and Black-legged Kittiwake versus birds such as Black-headed gull and Common Tern which also nest inland. Those who watch seabirds at their local sites will find the discussion section interesting as it discusses factors such as population drivers. World birders may find the section on international context interesting, although some of the information is disquieting, for example, Black-headed Gulls appear to be in decline across Europe.

So would this book be of interest to bird watchers? I have to give a qualified yes. I would not pretend it is for everyone as it is dense with facts and figures. It is not a field guide and not a book meant to enthuse you to get into seabirds. It is for the already converted. In my own case, I love going on pelagics. I am just as happy watching seabirds from a land-based site such as RSPB Bempton Cliffs or being on a boat tour to Bass Rock. I am just happy to pause on my commute to the office to watch Herring Gulls and Lesser Black-backed Gulls on the River Thames. As I write this from my apartment in London, I can hear the haunting calls of Herring Gulls calling from the River Thames. I lead bird-watching walks for the London Bird Club (a section of the LNHS). Therefore, as I thumb through the species accounts, I find myself extracting information I can quote to share with others. For example, Britain and Ireland host as much as 43% of the global breeding population of Herring Gulls. The tables and graphs also bring into focus information which we may not have thought about consciously. For example, there are only 25 breeding sites for the Northern Gannet in Britain and Ireland although they hold 69% of the global population. But it is encouraging that they are showing a sustained increase in breeding numbers. There are also fascinating insights into their behaviour and ecology, interspersed throughout the various sections in the species accounts, especially in the introductory section. Northern Fulmars engage in a 6,000 km return trip when they go foraging. Amongst my favourite recollections of bird-watching moments are watching from atop a cliff top, Northern Fulmars gliding effortlessly and fast. Some of the information in this book will only reinforce the admiration bird watchers already have for seabirds.

25 species of seabirds from tubenoses, gannets, cormorants, skuas, gulls and tern to auks are covered in this book. Every seabird watcher will have their favourite seabird-watching moments with one or more species. The results of this book are very important and it will be an important baseline influencing management decisions. Although the book's results will be largely for conservation decision-makers, there is also a lot of information to interest the serious seabird enthusiast.