Oberservations on the ecology of Western Cape Cod Bay, Massachusetts

Oberservations on the ecology of Western Cape Cod Bay, Massachusetts

174 To be frank I like to read books dealing with the historical side of the fisheries, but this mass of little data and facts can only be digested in...

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174 To be frank I like to read books dealing with the historical side of the fisheries, but this mass of little data and facts can only be digested in very small portions (a few years), then interest fades away. Still it is an attractive book, with very nice illustrations, for those interested in the daily life of hard-working fishermen who struggled for their existence off the coast of East Fife when drift-netting was still possible. S.J. DE GROOT Netherlands Institute for Fishery lnvestitlations P.O. Box 68 1970AB-IJmuiden The Netherlands

WESTERN CAPE COD BAY Oberservations o n the E c o l o g y o f Western Cape Cod Bay, Massachusetts.

J.D. Davis and D. Merriman (Editors). Springer-Verlag, Heidelberger Platz 3, Postfach D-1000, Berlin 33, 1984, 289 pp., price DM58.00, ISBN 3-540-96084-8. What is the effect of "thermal p o l l u t i o n " on the marine biota? This question seems to be the main background for the present book, and the immediate reason for investigating the effect of "thermal pollution" is the construction and operation of the Pilgrim Nuclear Power Station (655 megawatt) in Western Cape Cod Bay, Massachusetts, U.S.A. The cooling water from the power station transfers large amounts of additional waste heat to the environment. Because o f scientific and public concern about the concominant effects of temperature increases, in-depth hydrographical and biological studies in the area were undertaken in 1969, 4 years prior to the start of operations by the power station. In the Preface, one of the editors (Merriman, u n f o r t u n a t e l y he died before the book was printed) claims that the concept "thermal p o l l u t i o n " is an u n f o r t u n a t e designation because the thermal alterations of waters adjacent to industrial effluent areas are not necessarily harmful. In certain cases and for certain species, such alterations may be beneficial or have no significant effects. He has therefore proposed that the concept "caleficat i o n " should be used, but, as he admits himself, his arguments have largely fallen on deaf ears. Cape Cod Bay is a rather shallow bay of about 796 km 2 in southeastern Massachusetts, bordered by land on the west, south and east, and to the north by the southernmost part of the Gulf of Maine. The average depth is about 25 m. There is much evidence for characterizing the bay as a biogeographical transitional zone between predominant boreal fauna elements in the bay and to the north, and more temperate fauna elements to the south.

175 The Pilgrim Power Station is not the only man-made alteration in the bay. In 1914, a canal was built between this bay and the adjacent Buzzards Bay, which has considerably higher water temperatures than Cape Cod Bay. Due to different tidal phases and amplitudes, there is considerable water flow (up to 2060 m 2 s -1) through the canal. In the canal, the temperature of part of the water is elevated because it is used for cooling an electric power station. Before the research program initiated by the planning of the nuclear power station, other investigations had been carried out in the bay and even more extensively in the adjacent Gulf of Maine, among others by the Marine Biological Laboratory at Woods Hole, Massachusetts. However, it is stated that Cape Cod Bay had received surprisingly little attention before 1969. The present book is a comprehensive monograph of the hydrography, flora and fauna of Cape Cod Bay, especially of the western part where the man-made constructions (power station and canal) are located. Impact by the warm water masses from the power station and the canal is the red thread t h r o u g h o u t the book, but in my opinion, the studies of the resources and biological production in the bay are an equally valuable scientific contribution. The only recorded influence by the canal from Buzzard Bay seems to be the transport of lobster larvae from the canal to the southwestern part of Cape Cod Bay, thus giving the possibility of a higher population there than could be obtained by natural recruitment. Concerning the influence of the nuclear power station, the physical effects are not easy to quantify. For instance, what is the real temperature increase and how is the waste water distributed? Information on these items is more or less " h i d d e n " in the book. It is also difficult to find any clear biological/ecological effect of the elevated environmental temperatures. There are indications of the disappearance of some fishes from the immediate vicinity of the station when the water temperatures are at their highest (about 30°C in summer). Part of the difficulty is that natural fluctuations in year-class strength of fish or in biomass are very high, and there has been a general decline in the abundance of m a n y valuable species during the years the station has been in operation. However, this decline had started before 1972, and to some degree the abundance has increased again recently. Effects on phytoplankton, zooplankton, macroalgae, lobsters (larvae and adults), fish larvae and commercial and sport fisheries are obscure and generally rather small. One clear effect has occasionally been observed. Gas-bubble disease occurs when the water gets supersaturated with air (oxygen and nitrogen) during heating (or other physical alterations), and is similar to the caisson disease known by divers. In a few cases, great quantities of fish (43 000 menhaden in 1973) were killed by bubble disease. P h y t o p l a n k t o n passing through the cooling system seem to survive to a

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great extent, although it is also exposed to chlorination (to control biofouling in the machines). Survival rates ranging from 48 to 98% were recorded, b u t when the water temperature exceeded 29°C, mortality was nearly 100%. To sum up, it may be concluded that although little effect from so-called "thermal pollution" has been recorded, this b o o k is a valuable monograph on the assessment of resources and on ecological and biological as well as hydrographical studies in this interesting area. It also gives valuable baseline studies for later investigations when more serious man-made changes may threaten marine life in the same or in similar areas. Such a monograph should also be very valuable for other areas threatened by environmental man-made problems, for instance parts of the North Sea. G. N A EV D A L

Department of Fisheries Biology University of Bergen Nordnesgt. 33 N-5000 Bergen Norway

FISH CATCHING METHODS

Fish Catching Methods o f the World by A. von Brandt. 3rd Edn. Fishing News Books, Farnham, 1984, 418 pp., 733 figs., 690 refs., £27.50, ISBN 0-85238-125-5. This must be regarded as the standard, general reference on fishing techniques used t h r o u g h o u t the world. It is a source of basic information on fishing gear and methods; the place to start in the field of fishing technology. It is descriptive rather than analytical, conceptual rather than detailed, comprehensive rather than specialized, narrative rather than mathematical. Its wide appeal is substantiated b y the appearance of this third edition, and each edition, revised and enlarged, has been twice the size of its predecessor. This exponential growth is the result of the author's wish to cover all fishcatching methods, not just those of contemporary commercial importance. The contents are ordered in a systematic and progressive w a y through 31 chapters, showing the evolution of fishing principles from the simple to the more complex and sophisticated. There is considerable cross-referencing within the text, relating various concepts to one another, and the three indexes (Subject, Species and Product, Geographical) make it easy to relocate ideas. For those wishing to pursue specific ideas in greater depth, there is a substantial bibliography o f 690 references in many different languages. The language of most non-English references is identified. This is not so for the German and French references, but in these cases, the title usually reveals the language. For readers whose first language is English