Having always considered my bird call identification skills to be rather
average, and prompted by a couple of positive reviews, I recently bought a copy
of "The Sound Approach to Birding". This is a book that comes with two CDs of
bird calls, which was published in Europe within the last couple of months.
The authors are Mark Constantine and 'The Sound Approach', a group of birders
who have been trying to assemble a collection of recordings of all known calls
of western Palaearctic species in recent years.
The book is designed to educate birders about bird calls, and makes extensive
use of sonograms to analyse calls and illustrate points. It starts off by
highlighting how impossible it is to describe differences in calls in words as
field guides attempt to do. It gives examples of the variety of calls ranging
from the booming of bitterns to the high frequency trilling of warblers. It
then moves on to examining what the sonograms of a variety of calls look like
so that your understanding of sonograms develops as you read.
It examines various closely related species that have similar calls and shows
the differences between them - ranging from calls such as Reed versus Marsh
Warblers where the calls are very similar and distinguishing them is a matter
of examining the relative speeds, through to a comparison of similar calls of
Firecrest and Goldcrest. In that case each has a 'zit' call that contains four
notes. The sonograms reveal that the Firecrest's call is made up of a slightly
longer first note then three the same. The Goldcrest's are all the same. Sure
enough when you hear the recording you can tell the difference, but I do not
think I would ever have been able to describe the difference on the basis of
just listening to the recordings.
Other topics covered - and generally all illustrated by several recordings -
include: the effect of distance and habitat type on how sounds travel; how
songs are often most complex as birds establish territories and become simpler
as the breeding season goes on; how young birds' call skills develop with time;
mimicking of other species; and the different range of calls species use in
different situations (e.g. alarm calls, mating calls, calls used in territorial
disputes).
Lots of attention is given to differences in calls between different
populations. In some cases that has already led to species being split (e.g.
Iberian Chiffchaff from Chiffchaff); in others they are regarded as separate
subspecies (e.g. different populations of European Storm Petrels). There is an
extensive analysis of Crossbill calls from around Europe, all of which seems to
illustrate that the taxonomy of that group is even more complicated than
previously thought. Most of this has been published previously by one of the
authors. It seems Common Crossbills in Europe can be split into six different
types based on calls. In many cases there are subtle differences in
measurements as well. It is interesting that molecular analysis does not
reveal differences between the groups, though a new technique used on American
crossbills this year may have more success. But it seems that the birds pair
based on call types, and the call types don't depend on age or sex. So its
possible that these populations are good biological species - and if that's the
case, given that it's only the calls made just before flight and excitement
calls that are distinctive, it would mean birders have very little chance of
telling what species they are looking at.
The recordings are generally of very good quality: put on a pair of headphones
and you can hear the flying Woodcocks circling around you. One interesting
track interposes Marsh Warbler imitations of five species with the same calls
being given by the species being mimicked - the similarity is far closer than I
would have expected. Of course none of the calls is of Australian species.
Does that matter? Certainly it's more interesting if you are familiar with the
birds you're listening to. But the intention of the book is to teach you how
to recognise and analyse calls and the points can be made without you knowing
the species concerned. However it's interesting to consider whether all the
generalisations they make that might be accurate in Europe where so many birds
are migratory and territories have to be re-established each year apply equally
in Australia where there is less migration and more co-operative breeding.
Downsides? At GBP30 plus postage it's no bargain, but you do get two CDs as
part of that. The book is well produced with many photographs and the
sonograms are in colour. There's the odd typo and a couple of the cited
references aren't in the bibliography. It's written in an informal style
that's a bit too casual at times but that's a matter of personal preference.
And the way they use "The Sound Approach" interchangeably to describe
themselves as a group and the technique they use isn't ideal.
I have downloaded some free software developed by Cornell Uni called Raven Lite
which allows you to produce sonograms of calls from any recording including
CDs. So it's easy to produce sonograms of birds familiar to you if you want to.
The book isn't going to suddenly make you better at identifying birds by call -
you still have to learn the calls. But I think the book gives you a better
basis for analysing calls, and it does teach you how to learn to distinguish
difficult calls by using sonograms. I recommend it.
There is a website for the book including sample pages and ordering information
at http://www.soundapproach.co.uk
Murray Lord
==============================www.birding-aus.org
birding-aus.blogspot.com
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