Ecology and ethology of fishes Proceedings of the 2nd biennial symposium on the ethology and behavioral ecology of fishes, held at Normal, IL, U.S.A., October 19–22, 1979. Edited by D.L.G. Noakes and J.A. Ward. Printed as a special edition of

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Ecology and ethology of fishes Proceedings of the 2nd biennial symposium on the ethology and behavioral ecology of fishes, held at Normal, IL, U.S.A., October 19–22, 1979. Edited by D.L.G. Noakes and J.A. Ward. Printed as a special edition of

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  63 zyxwvut problem. It results from a technical consultation which took place in George- town, Guyana, in October, 1981, and gives s. very broad technological and geographic view of the subject. It has 33 papers, 9 of which describe developments in shrimp-fishing and in the utilization of by-catch in coun- tries across the world; 4 papers deal with marketing and economics. Ten of the papers deal with processing, but to my technologically untutored mind, what is said in them has a circumstantial, but not a precisely tech- nological relevance to by-catch exclusively; that is to say, it is probably relevant to such species however caught. In my view the papers of special interest are those by Sternin and Allsop (Strategies to avoid by-catch in shrimp trawling) and Caddy (Management of shrimp fisheries), and I venture to expose this view in the name, not of fisheries biology, but of fisheries science. Together, these papers direct attention to the logic and possibilities of sn avoidance strategy whereas other papers (especially the excellent papers in the section on processing at sea) describe the practical courses to be taken in the event (and in the actuality for most shrimp fisheries today) that by-catch is unavoidable. I am confident that the volume will be of considerable interest to every- one engaged in, or concerned with, shrimp fisheries. Moreover, it is avall- able, free, in English, French and Spanish. zyxwvutsrqponmlkjihgfedc G L KESTEVEN 12 zyxwvutsrqpon ’Briens Road, Hursh~ille 220, New South Wales, Auptralia) ECOLOGY AND ETHOLOGY OF FISHES Ecofogy and Ethology of Fishes. Proceedings of the 2nd biennial sym- posium on the ethology and behavioral ecology of fishes, held at Normal, IL, U.S.A., October 19-22, 1979. Edited by D.L.G. Noakes and J.A. Ward. Printed as a special edition of Environmental Biology of Fishes 6 (1). 1981. Junk, The Hague, 144 pp., Dfl. 65.OO/U.S. 34.00, ISBN 90-6193-821-X. This small volume is the first in a series entitled “Developments in En- vironmental Biology of Fishes” and presents a selection of 13 papers pre- sented at the conference, that were among a total of 49 by some 100 auth- ors. The papers included in this volume range from biochemical studies of alarm substances, to methods of documenting three-dimensional struc- ture of fish schools, courtship and mating patterns, parental behavior, and community relationships. The first three papers are devoted to schooling behavior. In order to  6 determine what selective pressures have been significant in the evolution of schooling behavior, it is first necessary to be able to describe schooling precisely. The first paper presents a new stereophotographic method that has promise in providing data on the 3-dimensional relationships in a fish school. The authors conclude, based on a rather small sample size and observations of juvenile coho salmon, Oncorhynchus zyxwvutsrqponmlkji isutch, that fish schools are not org.anized in a rigid lattice structure, but rather, the in- ternal structure is in a constant state of flux. At present their technique is limited to use above the water surface and does not seem to be suited to open ocean work. It may be useful, however, in the clear waters of shallow tropical seas. The use of computer graphics in anal-y .Lg fish school structure is de- veloped by M.J. Fotel and R.J. Wassersug in the second paper. They iden- tify three problems intriisic in studies of schools: (1) volume of data, (2) analysis of motion,, and (3)‘multiple spatial dimensions. The approach is limited to uses in situ where there are at least six reference markers avail- able, such as marks on an anchor line. zyxwvutsrqponmlkjihgfedcbaZ A variety of selective pressures have been advanced to explain the func- tion of schooling in fish, but little hypothesis testing has resulted. In the third paper, B.H. Seghers examines facultative schooling in the spottail shiner (Nob-o& hudsonius). Seghers states that theoretical models in socio- biology have emphasized the role of food resources and predator defense as major ultimate determinants of sociality. Therefore, if an individual is less susceptible to predation in a group, it should be able to reduce its vigilance for predators, thereby gaming time and energy for other activ- ities. Results of 176 tests show that two or more shiners have a signifi- cantly sharter reaction distance than solitary shiners. Schooling should be disadvantageous for this planktivore because fishes’ zyxwvutsrqponml isual fields over- lap, resulting in increased competition for food, while field data show that predators selectively attack single individuals. It seems that the shiners have reached a compromise between these two opposing pressures, for in nat- ure the shiners occur in relatively small schools. The function of the alarm pheromone of Ostariophysian fishes is ex- amined in the next paper: E.J. Heczko and B.H. Seghers find that the presence of alarm substance caused an increase in cohesion and polariza- tion in schools of the common shiner (N. cornutus) when compared to control schools. In the fifth paper, the presumed sex pheromone of the zebra fish Brach- ydanio rerio) is partially characterized and, using thin layer chromato- graphy, F.D. Algranati and A. Perlmutter find that the attractant is lo- cated in the cholesterol ester band They also examined the effect of diet on attractiveness and found no effect. Competition between a species of bisexual and two of its gynogenetic unisexual female spectes of zyxwvutsrqponmlkjihgfedcbaZYXWVUT oecilia in Mexico is examined in the next paper. The authors infer that at least three mechanisms exist to reduce  65 competition among the three species. These are: (1) each type of female uses the services of the males at different times of the year. (2) the females use different segments of the river, and (3) diffarent microhabitats within a segment of the river are used by the two species of gynogenetic females and the bisexual species. In another paper dealing with Poeciliid fishes, R. Borowsky and J. Diffley examine the demographic parameters of Xiphaphorus uariatus in Central America. They find that synchronized maturation and breeding are due to seasonal suspension of reproduction by females during the dry season when water temperature is high and available oxygen low. It appears that the return of good conditions triggers the resumption of reproduction. A group of females exposed to the same environmental t.rigger would, there- fore, be synchronized. In the bluegill sunfish, competition among males for females appears to have resulted in the selection for alternative male reproductive strat- egies. Wallace Dominey reports that some males become obligate female mimics and these males fool nest-guarding males by courting them. Even- tually, the mimics are able to fertilize at least a portion of the eggs spawned in the nest of the territorial male. Six percent of the nests examined were frequented by female mimics. Patterns of parental investment, dispersal and size among coral reef fishes are examined by George Barlow in the ninth paper. Among the coral reef fishes postzygotic investment seems to be limited to small fishes with demersal eggs. The larger fish do not show postzygotic investment in the young, but rather, are high fecundity, broadcast spawners. Barlow, after review of more than 170 references, concludes that the above dichotomy between large and small coral reef fishes is the result of selection for dis- persal of propagules in the large fishes. Postzygotic investment may be expected in general when (1) high morta ity of the young stages occurs in the absence of some form of parental care, (2) the fecundity of the parent is limited by small size or short breeding season, and (3) when the adult may function as the disperser. The next two papers deal with the reproductive tactics of cichlid fishes in their natural habitats. M.H.A. Keenleyside and B.F. Dietz describe the behavior of pairs of eguidens uittat~a in Surinam, South America, and find that there is a slight division of labor in this biparental species. Males attack conspecifics at greater distances from the nest than females. Fe- males, on the other hand, mouthed their eggs more, fanned more and moved the leaf on which the eggs were spawned more often. Two Asian cichlids of the genus Etroplus have been the subject of an extensive eighteen month study by J.A. Ward and J I. Samarakoon. Nest site selection in E. maculatus appears to be a compromise between the disadvantage of increased predation brought about b] nesting in tile open and the advantages of colonial nesting. Etroplus suratensis does not nest in colonies, but is successful because both members of the pair are con-  66 tinuously zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONM igilant over their young. In E. macuiatus, only one member of the pair cares for the young at a time. In the next paper, the causes of habitat segregation among adults of four species of sticklebacks are examined in a salt marsh by J.P. Worgan and G.J. FitzGeraJd. They find that there is a slight separation in breeding periods among the fishes and the role of interspecific competition is dis- cussed. Tie last paper deals with the strucb~re of a temperate reef fish com- munity in King Harbor, California. Diversity in this artificial habitat is believed to be related to its ecotonal nature and the fish community struc- ture appears to be the result of a non-equilibrium process. The large species present at any particular time are the result of larvae that have success- fully dispersed. It is the random fluctuations in these highly fecund species that result in much of the observed diversity. The remaining 16 pages contain 43 abstracts of papers presented at the meetings. The papers included in this volume highlight the areas where emphasis is currently being placed in the study of the behavior and ecology of fishes. In the search for the selective prc,sures that have been responsible for the evolution of social behavior, attention is focused on a species’ pred- ators and prey. Additionally, both intra- and interspecific competition still attract a few investigators as areas worthy of understanding. The de- terminants of multispecies structure in coral reef communities dso con- tinues to challenge investigators. One area that is not covered in this volume is the behavior of the open ocean fishes. Perhaps this is because of the extreme difficulty encountered in observing fish behavior in the open sea. I recommend this volume for the specialist in fish behavior or ecology, and for others who may wish to understand the state of these sciences better. R.L. WYMAN Biology Department, h’urtwick College. Oneo.h, NY 13820, U.S.A. U.K. FISHING GEAR TERMS Qlossary zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPON f Utiited Kingdom Fishing Gear Terms. J.P. Bridger, J.J. Foster, A.R. Margetts and ES. Strange. Fishing News Books, Surrey, 1981, xi + 114 pp., 33 illus., C15, + 11.50 post/packing, ISBN 0-85238-119-O. This excellent reference has been much needed for a long time. It fills a very real gap in fishing gear references and is sure to find its way onto
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