The Blue Tit

For most of us, the Blue Tit Cyanistes caeruleus will have been one of the first birds we saw as a child, and so it holds a special connection for many people. Even if you were not interested in birds you may have enjoyed making a nest box at school – and the main beneficiary would probably have been Blue Tits. Our strong affiliation with this species continues well into adult life. For example, 100 scientific papers are written about factors affecting Blue Tit ecology every year and of the 268 bird species ringed in the UK in 2016, the largest number were Blue Tits – with over 100,000 of them! Indeed over 4 million of them have been ringed in the UK in just over a century! So, it comes as a surprise to me that until now there has never been a monograph about this common breeding species.

Martyn Stenning has studied Blue Tits in Sussex for many years and wrote a PhD thesis on them in 1995. In this book, he combines his own work with that of many other researchers across Europe. An initial chapter gives a very good overview of how Blue Tits live, and on its own this section alone would make an excellent small publication, describing some of the challenges they face and the solutions they have developed to succeed.

There are nine generally accepted races of the Blue Tit with one – obscurus – which is unique to the UK. Closely related (and formerly lumped with Blue Tit by some authorities), the African Blue Tit Cyanistes teneriffae has seven races of its own in North Africa and the Canary Islands. Both this species and the Azure Tit Cyanistes cyanus are discussed.

Population structure, demography and mortality is the subject of another chapter, with extremes being very much evident. Some Blue Tits live in remote primaeval forests in Eastern Europe, while others live right alongside us, nesting in a wide range of cavities. This is an extraordinarily successful species, adapting to a modern world and thriving. Indeed, the UK population is rising when so many other species are doing badly. Another chapter explores the determinants of Blue Tit breeding success. On the one hand, Great Spotted Woodpeckers can help Blue Tits by creating holes in trees and widening existing cracks, but also at other times they prey upon the Blue Tits themselves. Bringing research together from across Europe the author compares data on the timing of nest-building and egg-laying, with the birds being able to delay the hatching of their chicks in the event of a cold-weather spell. Such studies are the subject of another chapter which reviews major analyses of Blue Tits over long periods of time. Finally, there is a discussion on anecdotes, folklore and poetry where writers have celebrated Blue Tits in many ways.

Several tables summarise results from the author’s own research in Sussex, and around 350 papers are listed for future reference. As has become the norm with Poyser monographs, there is a huge amount of detail about every aspect of Blue Tit life within the six chapters. There is a lot of information packed into this book, but written in a friendly style that demonstrates the author’s real affection for the species. Line drawings by Alan Harris break up the text, and there are eight pages of colour photographs of the various Blue Tit races and some aspects of the research discussed. At last, one of our commonest birds has been given the full treatment that it deserves!