Eggs and larvae of North Sea fishes
Peter Munk & Jørgen G. Nielsen
Frederiksberg: Biofolia
1st edition, 2005
215 pp., ISBN 87 9131 924 2 (personal),
87 9131 929 3 (institutional)
Price 375 DKK
There is ample agreement among aquatic ecologists and ichthyologists that fishes in their early stage of life can provide essential information for evergreen research topics such as ecosystem function, local recruitment and dispersal, or lower vertebrate evolution. However, the overall diversity of fish larvae has rarely been addressed in research and academic education. Much of the knowledge of fish larvae ecology and morphology has traditionally been restricted to either economically relevant species or geographical areas where some increased research emphasis has occurred during a distinct time period.
Clear statements that there is a pressing need for more diversified research and scientific exploration into fish larvae ecology and morphology have been made recently during the 7th Indopacific Fish Conference in Taipei, Taiwan (http://www.twichthyology.org/ipfc7/) by two renowned ichthyologists, Dr G. David Johnson of the US-based Smithsonian Institution and Dr Jeffrey M. Leis of the Australian Museum. The sad status that “… most ichthyologists are not trained in, or even exposed to, the handling, identification, and study of tiny fish larvae”, as Dave Johnson put it in his keynote talk, needs to be changed. There are admittedly several reasons for this unfortunate situation, but one of the most simple and frequently overlooked is the lack of proper and easily accessible identification literature. The book of Peter Munk and Jørgen G. Nielsen therefore comes at the right moment to fill gaps in knowledge and facilitate diversity-oriented ecological and ichthyological research on marine fish eggs and larvae in the North Sea and adjacent areas.
This handsome book contains three major parts with an introduction on research history and methods followed by guiding comments on fish egg and larval development and explanations about the organization of the subsequent species descriptions. In the following major section, detailed information on adult characters and biology, early stage characteristics (e.g. egg, yolk sac, pre-flexion, flexion, and post-flexion stage) and distinct larval characters is provided for a total of 96 fish species. Each species description is supplied with high-quality illustrations mostly consisting of five drawings showing the eggs and the four main larval stages on the facing page. For each drawing the original specimen size and reference to the model used are provided. The drawings show both internal and external body structures as well as pigmentation patterns in a clearly distinguishable and well-balanced manner that enhances the immediate recognition of important diagnostic characters.
The order of appearance is according to families, with the respective family indicated in the heading line of each page. On the description page each species is listed giving the English and the scientific name in the bold heading and the Danish, German, Spanish, French, Dutch, Norwegian, and Swedish common names in the sub-heading. While this greatly helps quick information acquisition for an international readership, a minor disadvantage is that the species have not been ordered alphabetically according to their English or scientific names. To give an example, one has to actually browse backwards from blue ling, Molva dipterygia, to arrive at ling, Molva molva.
The last part of the book consists of three appendices, with the first two providing very practical overviews of spawning periods and size ranges of egg diameters for a large number of the treated species, and the third showing 18 discernible fish egg stages in the case of plaice, Pleuronectes platessa. The comprehensive reference list with 168 citations is followed by two separate indices for the scientific and English names.
All in all this book is a very useful source of information for aquatic ecologists, fisheries biologists, ichthyologists and interested laymen. It should also prove to be a highly appreciated tool for academic education and field and museum collection work. Absolutely a must for libraries dealing with any of the aforementioned aspects! And there is even a further motive to buy and thoroughly study this book: to learn more about marine biodiversity in general. In a time where fisheries, pollution, climate change, and other human-induced factors impact life in our oceans like never before, the need to catalogue all species and all life history stages increases in order to allow proper registration and evaluation of the impact on local, regional, or global marine biodiversity. For this purpose this book makes a good contribution indeed and hopefully also for the dawn of a new era of appreciation, exploration and research integration of fish egg and larvae diversity.
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark