The end of April is a perfect time to write a review of a new book on bird migration: birders across the UK - myself included - are looking for returning birds, or being serenaded by the songs of migrant warblers like Blackcaps and Chiffchaffs that have already reached their breeding territories (and seem determined to let everyone know it!). It’s an incredibly exciting time of the year, full of wonder and mystery and trying desperately to remember what the sub-song of a Whitethroat heard from 400m away might sound like.

On the other side of the Atlantic (I live in Wiltshire in western England) birdsong is similarly building up. Waves of migrating birds are returning to coastal hot-spots, to patches of scrub or woodland across a whole continent, and to nest-boxes that have remained empty and silent all winter to begin the breeding cycle for yet another year.

Migration is in full swing and millions of birds are moving between established wintering areas and traditional breeding areas. That’s how it’s been for millenia, and that’s how it’ll be for the foreseeable future…

Or is that almost ‘fixed’ view a far too simple a way of looking at migration, which as described in Ian Newton’s wonderful new book (the 113th in the acclaimed New Naturalist series, which concentrates - please note - on British natural history) is a term used ‘to signify a regular return movement of birds each year between separate breeding and wintering areas‘?

Of course it is.

The factors impacting upon the amazing ‘regular return movement’ - of thousands of kilometres in the case of species like Barn Swallows and Arctic Terns - are complex, varied, sometimes subtle sometimes brutal, and ever-changing. Some of those coastal hot-spots (here and overseas) are only ‘busy’ if the conditions (wind direction, cloud-cover and the like) are right for a ‘fall’; many of those backyard or ‘wasteland’ patches of scrub have been built over and are no longer available to migrants (or residents) with consequences we’re only just beginning to understand properly; and some of those nest-boxes will remain empty despite the local environment appearing unchanged. Changes in climate, to wintering habitats, to populations of prey species (like invertebrates or even other migrating birds), to the attitudes of the human populations that migrants interact with en-route can all have significant impacts on migrating birds - and therefore on bird migration.

While we’ve known for many years what the physiological triggers that cause migration are (summed up in the great pub quiz term ‘zugunruhe‘), migration, or what we understand of it, is changing right in front of us. Surveys show that migration timings seem to be shifting in some (particularly insectivorous passerine) species in responses to climate change that in turn is causing insects to emerge earlier (many birds aren’t keeping up, which will undoubtedly mean that some will be unable to raise their young). Some populations of a very few migrant species seem to be losing the migratory urge all together (how long before I can have no idea whether the Blackcaps and Chiffchaffs I’m listening to today haven’t just overwintered instead?). On a purely technological note the tiny size of today’s radio transmitters means that researchers are now able to gain important insights into where migrant birds refuel, how fast they travel, and what causes them to stop, linger, and continue. (Though not in the book in the last few months the remarkable overland migration route used by Eleonora’s Falcon has been traced through the use of lightweight radio transmitters. Before this discovery the accepted wisdom was always that they used a coastal route between Europe and Madagascar.) Online sites now allow users to virtually follow individual migrants as they move: more major discoveries undoubtedly await!

Migration is a vast, fluid, fascinating subject with many different layers of behaviour and interactions controlling it. And ‘Bird Migration’ (as far as I can tell anyway) looks at all of them, gives as many lucid explanations backed up with a wealth of references and statistics that anyone interested in migration as a subject could possibly want, and manages to do it without being overwhelmingly technical or using unnecessary jargon.

That’s not to say that ‘Bird Migration’ is always straightforward reading. I don’t mean that in any derogatory way whatsoever by the way: this is a subject that can either be looked at in a decent-length magazine article, or thoroughly explored in a detailed scholarly book of nearly 600 pages. Ian Newton, a hugely respected academic with a library of ornithological publications to his name (there’s a list here) was obviously commissioned to do the latter, and anyone who knows anything about the New Naturalist (NN) series would expect nothing less. This is a serious, in-depth study on migration, and is all the better for it.

Straightforward reading or not ‘Bird Migration’ is, however, always well-written, and brimming with enthusiasm, ideas, and intelligent observation. You may need to go back and read the occasional sentence twice (though that might just be me and my lack of scientific training), but there’s no language here that can’t be understood without giving the page proper concentration - and that concentration will be well rewarded.

There is a vast amount of information packed into this book. Divided into twenty-five chapters and numerous sub-headings (which makes ‘Bird Migration’ surprisingly easy to dip in and out of if there’s a particular aspect of migration you’d like to have up your sleeve to explain to, say, a potential Nature Walks client) the range of subjects that fall under the bracket of ‘migration’ is - as I alluded above - wide and constantly interesting and if an element of migration is worth discussing it will be somewhere in this book. Chapters end in a short summarising ‘thumbnail’ headed ‘Concluding Remarks’, incidentally, which are a quick way of becoming an ‘instant migration pundit’ (handy for those readers too time-constrained to read the whole book from cover to cover)

I was acutely aware as I wrote that last sentence - by the way - that as a birder rather than an ornithologist (if you don’t know the difference between the two you’re a birder) I’m not qualified to discuss whether some of the conclusions drawn in ‘Bird Migration’ are valid or not, but Professor Newton OBE, FRS, FRSE (to give him his formal title) has served as President of The British Ornithologists’ Union and the British Ecological Society, as Chairman of the Council of the RSPB and Chairman of the Board of Directors of The Peregrine Fund and has received numerous awards including the Union Medal of the British Ornithologists’ Union, and the Elliot Coues Award of the American Ornithologists’ Union. I think it’s pretty safe to say therefore that he knows what he’s talking about (indeed as he says in the Author’s Foreword, this present book is a reworked and up to date everyman’s version of a previous book “aimed primarily at professionals, including research students”). And just to further stress Professor Newton’s credentials this is his second NN volume - his first, ‘Finches’, received (and continues to receive) the critical acclaim this second book will surely collect as reviews are published.

I think it’s also safe to bet that if the information is published in a New Naturalist volume then it’s accurate and properly researched whether the reader entirely understands its conclusions or not. Whilst the presentation style of the New Naturalist series has modernised a little - this present book is enhanced with more than 200 beautifully-reproduced photographs and there are numerous coloured maps and diagrams which the older (revered and often very valuable) volumes in the series didn’t have - it hasn’t dumbed-down. An author still has to be a pre-eminent expert on their particular natural history subject to have their book published in the series.

That’s to publisher Collins’ credit. As far as I’m aware no NN volume has ever made the UK bestseller lists, and I don’t suppose many make much of a profit, but Collins nevertheless maintains a fearsome NN editorial board (the five standing members - a list of the Board members is given on page two of each volume - meet twice a year to discuss ongoing and upcoming projects) and evidently care very much about their sixty year old, 113 strong series.

We should all be grateful really, because books with this much information available in such an attractive and approachable package are becoming as scarce as some of the migrant birds that Ian Newton discusses in his book. From its distinctive spine to the quality of the paper and printing, the New Naturalist series has always been produced to the highest standards and at just 30GBP (for the softback version, which is the one I have) is superb value for money.

So would I recommend this book? It’s fair to say that if I’d have had to buy it myself (Collins kindly sent me a review copy) I’d have had to think long and hard - but that’s far more to do with my current financial situation than perceived value or the amount of information that ‘Bird Migration’ contains. If - like me - you have any interest at all in migration (focussing on Europe and Africa remember, but the mechanisms are universal), wondered how it evolved, why wintering birds don’t breed in apparently suitable habitat, what governs the routes migrants use, then without a shadow of a doubt you will be constantly turning to this profound and timely addition to what has always been one of the most important series of natural history books available on the planet. I learn something new every time I open its pages and will continue to do so for many years to come I’m sure (if I could only remember every nugget of information it contains I’d doubtless come across as one of the best informed bird guides in the whole of this part of Wiltshire…).

To borrow from a well-worn phrase, ‘Bird Migration’ will answer questions you didn’t even know you wanted to ask - and then some.

Price: £30.00
ISBN: 978-0-00-730732-6
Format: Paperback
Pub date: 01 April 2010