Thursday, May 24, 2007

"Sri Lanka Freshwater Fauna and Fisheries" by Fernando, C. H. & S. R. Weerewardhena (2002)

Sri Lanka Freshwater Fauna and Fisheries. Fernando, C. H. & S. R. Weerewardhena, 2002. A Third Millenium Book, Colombo, Sri Lanka, and Volumes Publishing, Kitchener, Canada. ISBN 955-97697-0-7. Orders to the authors at or

This weighty tome - 634 A4 pages – landed on my desk with a resounding thump. Its heft is due not only to physical bulk. C. Herbert Fernando, the senior author, has half a century of experience in tropical limnology, and is indisputably one of the founding fathers of this research area. The book is subtitled ‘A guide to the freshwater fauna and the genesis of inland fisheries’ and is made up of a number of papers by Fernando and his collaborators published between 1956 and 2002. There is only one item in the book that has not appeared elsewhere, and it the only paper that features the two authors. The original papers do not seem to have been modified in any way. The lack of editing means that there are some redundancies in the text, but the difficulty of obtaining some of Fernando’s original papers means that a reprint of this type is welcome. It is also helpful to have these papers bound collated into a single volume. I stress here that this volume is by no means a full representation of Fernando’s prodigious output.

A particular pleasure is to come across Mendis & Fernando’s seminal guide to the freshwater fauna of Sri Lanka (then, of course, called Ceylon). This 160-page paper is in itself a small book. It covers all major groups, from protozoa to otters, and is illustrated by the many delightful hand drawings of G.D. Kariyawasam. (My particular favourite is a picture of the Stork-billed kingfisher, Pelargopsis capensis.) I have my own, now rather dog-eared original of this paper and got a great deal of use out of it when I first started working in Asia. Of course, it is incomplete, and really only fully applicable to Sri Lanka, but it is an example of what is possible when a couple of young scientists decide to develop a tool that will help others make sense of a poorly known fauna. This first attempt was followed, over the years, but five supplements, each written by Fernando, plus papers on rotifers and copepods co-authored with collaborators. The fifth supplement was specially prepared by this volume by Fernando and Weerawardhena, and brings knowledge of the fauna up to date. Nomenclatural changes are taken into account also. As might be expected from Fernando’s own research interests in the group, zooplankton are particularly well covered in this volume. But this group aside, it is
probably true to say that the freshwater fauna of Sri Lanka is as well known, or perhaps better known, than any other tropical country of an equivalent size. There is still plenty to do, however. The Chironomidae (Diptera), for instance, are very poorly known but the family is likely to be highly species rich.

Papers that describe the development of freshwater fisheries in Sri Lanka, primarily reservoir fisheries, take up the rest of the book. These are based mainly upon the exploitation of exotic tilapias (sensu lato), there being no native fishes adapted to lacustrine habitats. This fact has encouraged Fernando to expound on his politically-incorrect view that exotic species can, under certain conditions, be valuable additions to local faunas (especially on pages 621 & 622). He quotes Charles Elton’s classic 1958 monograph on biological invasions (Elton, 1958) in support of this opinion, proposing that conservation should involve enhancing biological variety in as many places as possible, even if that means the addition of exotics. Moreover, Fernando thinks that that exotic species are not always threats to native biodiversity, suggesting that worldwide cultivation of chickens has reduced the pressure to harvest wild birds. There is something to be said for his views. Exotics have been and are being introduced throughout Asia in an unplanned, ad hoc manner. It may be better to accept that some exotics will arrive anyway, and manage or facilitate the introduction species that are least likely to impact native biotas. Many readers may disagree with Fernando’s view, but the evidence that he has assembled deserves careful consideration. Certainly, it should not be dismissed out of hand. I confess that as a native biodiversity chauvinist (i.e. native = good; introduced = bad), this was my initial reaction.

This volume contains a lot of useful information. However, some of it is hard to locate. A frustrating feature, although an understandable one considering its genesis, is the lack of an overall index. There are three partial indexes, which cover pages 162-422 and 445-485, and the contents of the original Mendis & Fernando paper. The third of these is well done, but a test of the first revealed that it was incomplete. From page 507 onwards there is no indexing at all. In order to find entries on a given taxon, the reader has to consult all three indices, but even then cannot be confident that a useful nugget of information hasn’t been missed.

On the back cover, the subtitle is slightly different from that on the frontispiece, and is given as ‘A guide to the freshwater fauna of Sri Lanka and a genesis of the fisheries’. The blurb goes on to say ‘ ... this is the only comprehensive book on the freshwater fauna and fisheries of any county in the world. It was written and updated over a period of nearly 50 years’. Need I say more?

Elton, C. S., 1958. The Ecology of Invasions by Animals and Plants. Chapman & Hall, London. 181 pp.

David Dudgeon
Department of Ecology & Biodiversity,
The University of Hong Kong,
Hong Kong SAR,

First published in The Raffles Bulletin of Zoology Vol. 51(1): 173-174 on 30 Jun 2003.

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