Developments in Environmental Biology of Fishes – Serie

Butterflyfishes of the family Chaetodontidae are conspicuous members of almost all tropical reefs. These colorful fishes have attracted a great deal of attention from both the scientific community and especially the aquarium fish industry. At first one is tempted to say that butterflyfishes are abundant worldwide, but the evidence does not support this statement. The biomass of chaetodontids on reefs may range from 0.02-0.80%, and in terms of numbers they comprise only 0.04-0.61 % of the individuals on the reef. Yet in spite of these relatively small numbers they have been extensively studied. A quick census shows some 170 articles on or about butterfly­ fishes, with 78% of them being published since the 1970's. Along with the cichlids and damselfishes they might be one of the most studied and well published family of tropical fishes. Why then have chaetodontids attracted so much attention? The butterflyfishes are mostly shallow water inhabitants that are approachable and easily recognizable, making their study very feasible. Their bright coloration has provoked many hypotheses but has posed more questions about coloration than it has provided answers. And despite their apparent overall morphological similarity, their highly structured and varied social systems have made them an ideal model for such studies. The reasons for choosing these organisms are indeed as diverse as the studies themselves.

Members of the family Cyprinidae dominate most of the aquatic habitats of Europe, from eutrophic warm water ponds to mountain lakes. The family comprises generalists and specialists, herbivorous, planktovorous and even one piscivorous species; slow-moving grazers as well as fast-swimming inhabitants of the pelagial of lakes. Due to their diversity and abundance, cyprinids play key roles in every ecosystem in which they occur. Being of little economic importance, however, the family has for the most part failed to arouse keen scientific interest. With the aim of drawing attention to this situation, and to encourage further research, a symposium was held in Salzburg, Austria. Experts from all fields of biology discussed ecological, morphological and physiological aspects of the lives of cyprinids. The publication of this collection of keynote contributions to the symposium documents the value of the comparative approach in biology.The structural and functional patterns which emerge provide hints regarding the evolutionary processes underlying the diversification and specialization of a family which, from the ecological viewpoint, is one of the most important of the freshwater fish of the entire world.

This volume originates from a symposium on the "Reproduction and Development of Cartilaginous Fishes" that was held at the annual meetings of the American Elasmobranch Society and the American Society of Ichthyologists and Herpetologists in Charleston, South Carolina in 1990. The cartilaginous fishes, class Chondrichthyes, are a large and diverse group of fishes that include approximately 900 to 1100 living species of sharks, skates, rays and ratfishes. Throughout their history, which dates back at least 400 million years, they have been a successful major component of the marine ecosystem. The chondrichthyan fishes occupy a pivotal position in comparative and evolutionary studies of vertebrate reproduction and development. They are the oldest surviving group of jawed vertebrates and they possess both the adult vertebrate Bauplan and the vertebrate program of embryonic development. The major features of the female reproductive system, including its embryonic origin, structure, physiological function, and biochemistry, were apparently established early in vertebrate evolution and are fully developed in chondrichthyan fishes.These features of the female reproductive system have been retained during the evolution of the other classes of vertebrates. Much the same can be said for the male reproductive system. Moreover, viviparity, placental nourishment of developing embryos, and the hormonal regulation of these events made an initial appearance in this group. The 22 articles presented in this volume bring together a wide variety of complementary research by investigators from seven countries allowing the scope and implications of studies to be broadened, while identifying opportunities for future research. The appearance of a volume on the reproduction and development of cartilaginous fishes is opportune. The continued existence of these fishes, which survived the great extinction events of Earth's history, is now threatened by overexploitation unless immediate steps for their conservation are undertaken. Knowledge of their reproduction and development not only is an end in itself, but is of critical importance in devising successful conservation and resource management strategies.

This text is dedicated to the contributions of women ichthyologists. Three colleagues were selected to represent all women ichthyologists, Ethelwynn Trewavas (ET), Rosemary Lowe-McConnell (Ro) and Eugenie Clark (Genie). All have had distinguished professional careers and have contributed in their own ways to their science. The career of each is highlighted by a personal interview with one of the editors of the volume, a bibliography of their lifetime publications, and a biography of their careers. Questions of historical inequities and current controversies in the treatment of women ichthyologists by their peers are raised and addressed by the women themselves. The personal and professional influences of these three women, and other women ichthyologists, are highlighted. A survey article by Pat Brown brings a number of women ichthyologists to the attention of a broader audience, and points the way for a more comprehensive historical consideration of the accomplishments and contributions of women ichthyologists. The volume continues with 16 solicited and contributed papers.ET's studies of taxonomy and life history are echoed in papers on the taxonomy and systematics of marine angelfishes, and of freshwater bitterlings, a review of reproduction in the North Atlantic ichthyofauna, and a comparison of reproductive styles and systematics of African minnows. Ro's studies on ecology, life history and behaviour are paralleled by papers on growth and metabolism in piranha, the community structure in tide pool fishes, and the social system and reproductive patterns in groupers. Genie's pioneering work on sexual roles and sex change, and her field studies of the behaviour of marine fishes are reflected in papers on gonadal structure and environmental sex determination in brook lamprey, sexual patterns in hawkfish, reproduction and systematics in phallostethids, gonadal structure and systematics in gobiids, reproductive and predator avoidance behaviour in razorfish, early ontogeny of an African mouth brooder, and alternative life histories in killifish.

Ecomorphology is the comparative study of the influence of morphology on ecological relationships and the evolutionary impact of ecological factors on morphology in different life intervals, populations, species, communities, and evolutionary lineages. This study reviews early attempts at qualitative descriptions of ecomorphological patterns in fishes, especially those of the Russian school. More recent, quantitative studies are emphasised, including multivariate approaches to ecomorphological analysis, the selection of functionally important ecological and morphological variables to analyze, an experimental approach using performance tests to examine specific hypotheses derived from functional morphology, and the evolutionary interpretations of ecomorphological patterns. Six major areas of fish biology are focused on: feeding, sensory systems, locomotion, respiration, reproduction, and phylogenetic relationships.

Acipenser brevirostrum female 58 cm long from the Hudson River near Kingston, New York, above Acipenser oxyrinchus male 58 cm long from the Lawrence River near St. Vallier, Quebec, by Paul I. Voevodine from Vladykov & Greeley (1963). 1 Sturgeon landing on the Volga River. From an engraving in Moynet . p. 85. 1 Moynet, M. 1867. LaVolga. LeTourduMonde15: 81-96. Environmental Biology of Fishes 48: 373-380,1997. (c) 1997 Kluwer Academic Publishers. Printed in the Netherlands. Sturgeons and the Aral Sea ecological catastrophe Iliya Zholdasova Institute of Bioecology, Karakalpak Branch of the Academy of Sciences of Uzbekistan, Nukus, Republic Ka- kalpakstan Received5.4.1995 Accepted16.3.1996 Key words: Amu-Dar River, Syr-Dar River, Pseudoscaphirhynchus kaufmanni, P. fedtschenkoi, P. hermanni, Acipenser nudiventris, pollution, acclimatization, Nitzschia Synopsis A short description of the catastrophic changes in the ecology of the Aral Sea basin during the three last decades is presented. These changes have influenced the status oftwo acipenserid endemics to the area, the large Amu-Dar shovelnose, Pseudoscaphirhynchus kaufmanni, and the ship sturgeon,Acipensernudiventris.The main biological characteristics ofboth species in the new environmental conditions are given. Previous unsuccessful attempts to introduce other acipenserid species into the area are also described. International cooperationisneededforsavingthelastsurvivingspeciesrepresentingthegenusPseudoscaphirhynchus.The only twootherspeciesofthe same genus, P.fedtschenkoi and P . hermanni, have alreadybecome victims ofthe Aral Sea catastrophe and are apparently extinct. Introduction 1993). Twosturgeonspecies, the Syr-Dar and small Amu-Dar shovelnose sturgeons, were among the Historically the endemic fauna ofthe Aral Sea ba- first victims of this disaster and seem to be extinct.

Hiroya Kawanabe (HK) was born in Kyoto on 10 May 1932. His father, Osamu Kawanabe, was a teacher of Japanese literature and also a Buddhist priest, who died in 1934 at an early age. His mother, Tsuya Fujii-Kawanabe, was a teacher of the tea cer- emony and of flower arrangement, and had given birth to him at age 38. He attended elementary school from 1938 to 1945, junior high school from 1945 to 1948, and Kyoto City's Ohki High School, from 1948 to 1951. In March 1945, military requisi- tion of the Kawanabe property, which was situated in downtown Kyoto, and the subsequent demolition of the family home necessitated the tearful and hasty removal of only a fraction of the family's be- longings in a cart (HK 490; numbers refer to the subsequent 'Lifetime list of publications by Hiroya Kawanabe'). He and his mother were able to save only a portion of his father's books; his passion for reading may be due to the influence of his father. Interestingly enough, during his junior high school and high school years, Kawanabe tried to improve the method used to catalogue the books in his school libraries, though he subsequently learned Figure 1.Hiroya Kawanabe during his convocation address on that the NDC (Nihon Decimal Classification) was the occassion of receiving Doctor of Science honoris causa at the the most convenient cataloguing method in com- University of Guelph, 5 October 1995. Photograph by M. mon use. Schwalbe.

Metamorphosis and the transition from larvae or embryos to juveniles in fishes are important in order to answer, for example, questions about: (1) life-history styles and their modifications in evolutionary perspective and within current environmental demands; (2) the development and application of fisheries recruitment models; (3) the use of ontogenetic scales for interspecific comparisons; (4) the identification of ontogenetic shifts in resource use; and (5) the discovery of evolutionary interrelationships of species or genera. This volume is dedicated to recent studies and reviews of existing knowledge on this insufficiently-addressed area of ichthyology. Most of the papers in this volume were presented in Bratislava, Slovakia, at the 1st International Workshop of the Fish Ontogeny Network of Europe (FONE) in September 1997, a meeting sponsored in part by the European Commission. This volume emphasizes an integrated approach to the study of fish ontogeny, which is a process during which one event is related to another and everything is related to everything else, encompassing physiology, morphology, behaviour and niche.

The elasmobranch fishes include the living sharks, skates and rays that are important members of nearly all marine ecosystems. Their large size, secretive behaviour, and wide-ranging habits make them difficult to observe in the field or to maintain in captivity. Consequently, little is known about their natural behaviour and how it is mediated by their sensory systems. This volume is dedicated to the scientific contributions and memory of Donald Nelson, a pioneer in the study of shark behaviour, sensory biology, and remote instrumentation. The two opening papers review Don Nelson's unique scientific accomplishments and provide insight into his strong bias towards study of animals in the field. These are followed by 14 scientific papers on elasmobranch behaviour, sensory biology, and current monitoring technologies. The papers on elasmobranch sensory biology and behaviour address questions on hearing, the lateral line, electroreception, the brain, orientation behaviour, chemical irritants, feeding, and reproduction.The latter section of the volume presents papers on conventional tagging techniques, ultrasonic telemetry, physiological telemetry, remote monitoring techniques, archival tagging and satellite tagging. The intent of this volume is to familiarize both new and established scientists with the sensory biology and behavior of sharks and rays, and to encourage further behavioral research on these animals in their natural environment.

This volume delves into the mechanisms and early principles of developmental psychobiology, neurobiology, and behavioral ecology. It reflects the three mainstreams of the discipline of proximal and biographical influences: neural mediation; development and flexibility and functionally significant changes that occur in the habitats of many species; as well as how connections have been forged among the disciplines.

The Salvelinus species is one of the most thoroughly studied groups of fishes and there are many reasons for this intense interest in charr biology. Charr have an Holarctic distribution encompassing many Asian, North American and European countries and occupy diverse marine and freshwater environments. Furthermore, the current distribution of charr includes areas that were directly influenced by climate and topographic change associated with the many Pleistocene glaciations. Undoubtedly, these conditions have promoted much of the tremendous morphological, ecological and genetic variability and plasticity within Salvelinus species and they make charr very good models to study evolutionary processes "in action". Many charr species also exhibit demographic characteristics such as slow growth, late maturity and life in extreme environments, that may increase their susceptibility to extinction from habitat changes and overexploitation, especially in depauperate aquatic habitats. This vulnerability makes understanding their biology of great relevance to biodiversity and conservation.Finally, charr are of great cultural, commercial and recreational significance to many communities, and their intimate linkage with human societies has stimulated much interest in this enigmatic genus. This volume comprises of a selection of papers presented at the fourth International Charr Symposium held in Trois-Rivieres (Quebec, Canada), from 26 June to 1 July 2000. It includes 31 papers on ecological interactions and behaviour, trophic polymorphism, movement and migration, ecophysiology and evolutionary genetics, ecological parasitology, environmental stress and conservation. These studies cannot cover all recent developments in the ecology, behaviour and conservation of Salvelinus species, but collecting them into one volume should bring attention to current research on this important genus and stimulate further work on Salvelinus species.

Fisheries genetics researchers will find invaluable the thirty-eight peer-reviewed contributions in this book, presented at the 20th Lowell Wakefield Fisheries Symposium "Genetics of Subpolar Fish and Invertebrates," held in May 2002 in Juneau, Alaska. Looming over concerns of lost fisheries stocks and persistent erosion of genetic variability are predictions of global warming, which may further tax genetic resources. One consequence is an increased reliance on genetic applications to many aspects of fisheries management, aquaculture, and conservation. The contributions in this book are important to modern fisheries science and genetics, and illustrate the evolution of the field over the past decade. The improved technology provides tools to address increasingly complicated problems in traditional applications and ecological and behavioral studies. The union between molecular and quantitative genetics, where many of the major questions about population structure and evolution remain unanswered, will also benefit from the new technologies.

This book is the first complete biography of one of the founders of fishery science, William Edwin (Bill) Ricker (1908 - 2001). Bill is immortalized in the Ricker Curve. He developed the Curve in his studies of stock and recruitment in fisheries, but it has been widely applied in many areas of science. Bill is best known for his contributions to fishery science, but he was also internationally recognized as an entomologist and a scientific editor. This book combines Bill’s own recollections with contributions from those who knew him and worked with him as a colleague during his multifaceted career. In an article written shortly before his death, Bill gives his own account of his career and intellectual development. A complete bibliography of Bill’s scientific publications, translations and manuscripts has been compiled by his son Karl, and accompanies this article. Karl has also written a detailed account of Bill’s early education and his accomplishments in botany and ornithology. Geoff Scudder summarizes Bill’s contributions to entomology, Jon Schnute provides both personal and professional insights into Bill’s mathematical accomplishments, and Dick Beamish and Don Noakes present personal recollections of Bill as a scientist and colleague.

Over the last few years there have been advances in the quantitative study of age and growth of chondrichthyan fishes. Novel approaches to ageing of various chondrichthyan fishes continue to arise. This volume is a collection of papers on several of these topics that include new hard parts (e.g. caudal thorns) for assessments of age, new techniques for validation (e.g. bomb radiocarbon) and reexaminations of previous age and growth models. This volume also contains papers on the importance of assessing the precision and accuracy of statistical formulas, analyses, and models that are used in age and growth studies. There is currently a great deal of research being conducted, some of which is truly "pushing the envelope," in attempts to assess the life history parameters of numerous chondrichthyan fishes.

This book represents the outcome of a symposium held in Indianapolis, Indiana on 28–30 October 2005. The symposium was an international program on the ecology and management of muskellunge and was held in memory of Dr. Edwin J. Crossman. The symposium structure was largely similar to the original International Musky Symposium, held in LaCrosse, Wisconsin in 1984. It was intended to bring together academic researchers, management biologists, and practical musky anglers into a common venue to review the current status of knowledge on muskellunge and their management. The symposium was dedicated to the memory of Edwin J. Crossman. Dr. Crossman passed away on 21 December 2003, at the age of 74. While 74 is an advanced age for many people, Ed’s passing occurred far too young. He was retired from the University of Toronto and the Royal Ontario Museum, but still an active researcher in ?sh systematics and muskellunge ecology. Dr. Crossman was in?uential in developing the knowledge of muskellunge we have today and encouraging many people to follow in his footsteps in the studies of muskellunge and their relatives. The concept of a second musky symposium began with conversations between members of Muskies, Inc.

Skates have become a concern in recent years due to the preponderance of these elasmobranchs that are caught as bycatch or as a directed fishery. This has raised concern because skates have life history characteristics that may make them vulnerable to over-exploitation. It was due to this concern that prompted Drs. David Ebert and James Sulikowski to organize an international symposium on the “Biology of Skates”. The aims and goals of the symposium were to bring together an international group of researchers to meet, discuss, perhaps develop collaborations, and present their most recent findings.The symposium was held over two days, on 13-14 July, 2006, in conjunction with the 22nd annual meeting of the American Elasmobranch Society in New Orleans, LA. A total of 31 authors from four countries contributed 16 papers that appear in this volume. The papers are broadly arranged into four separate categories: systematics and biogeography, diet and feeding ecology, reproductive biology, and age and growth. This is the first dedicated book on the biology of skates. We hope that readers will find this volume of interest and that it helps encourage and stimulate future research into these fascinating fishes.

The information on their carp species will be invaluable to those in other countries who will either take advantage of the productive carp species in aquaculture or try to manage them as invasive species outside China.

This volume had its origin in a symposium on the Reproduction and Development of Cartilaginous Fishes that was held at the annual meetings of the American Elasmobranch Society and the American Society of Ichthyologists and Herpetologists in Charleston, South Carolina in 1990. The cartilaginous fishes, class Chondrichthyes, are a large and diverse group of fishes that include approximately 900 to 1100 living species of sharks, skates, rays and ratfishes. Throughout their history, which dates back at least 400 million years, they have been a successful major component of the marine ecosystem. The chondrichthyan fishes occupy a pivotal position in comparative and evolutionary studies of vertebrate reproduction and development. They are the oldest surviving group of jawed vertebrates and they possess both the adult vertebrate Bauplan and the vertebrate program of embryonic development. The major features of the female reproductive system, including its embryonic origin, structure, physiological function, and biochemistry, apparently were established early in vertebrate evolution and are fully developed in chondrichthyan fishes. These features of the female reproductive system have been retained during the evolution of the other classes of vertebrates. Much the same can be said for the male reproductive system. Moreover, viviparity, placental nourishment of developing embryos, and the hormonal regulation of these events made an initial appearance in this group. The 22 articles presented in this volume bring together a wide variety of complementary research by investigators from seven countries, allowing us to broaden the scope and implications of our studies while identifying opportunities for future research. The appearance of a volume on the reproduction and development of cartilaginous fishes is quite opportune. The continued existence of these fishes, which survived the great extinction events of Earth's history, is nowthreatened by overexploitation unless immediate steps for their conservation are undertaken. Knowledge of their reproduction and development not only is an end in itself, but is of critical importance in devising successful conservation and resource management strategies.

Ecomorphology is the comparative study of the influence of morphology on ecological relationships and the evolutionary impact of ecological factors on morphology in different life intervals, populations, species, communities, and evolutionary lineages. The book reviews early attempts at qualitative descriptions of ecomorphological patterns in fishes, especially those of the Russian school. More recent, quantitative studies are emphasised, including multivariate approaches to ecomorphological analysis, the selection of functionally important ecological and morphological variables to analyze, an experimental approach using performance tests to examine specific hypotheses derived from functional morphology, and the evolutionary interpretations of ecomorphological patterns. Six major areas of fish biology are focused on: feeding, sensory systems, locomotion, respiration, reproduction, and phylogenetic relationships. The 18 papers in the volume document: (1) how the morphology of bony fishes constrains ecological patterns and the use of resources; (2) whether ecological constraints can narrow the niche beyond the limits imposed by morphology (fundamental vs. realized niche); (3) how communities of fishes are organized with respect to ecomorphological patterns; and (4) the degree to which evolutionary pressures have produced convergent or divergent morphologies in fishes.A concluding paper summarizes ecomorphological research in fishes and points out taxa that are underrepresented or are especially promising for future research.

Hiroya Kawanabe (HK) was born in Kyoto on 10 May 1932. His father, Osamu Kawanabe, was a teacher of Japanese literature and also a Buddhist priest, who died in 1934 at an early age. His mother, Tsuya Fujii-Kawanabe, was a teacher of the tea cer- emony and of flower arrangement, and had given birth to him at age 38. He attended elementary school from 1938 to 1945, junior high school from 1945 to 1948, and Kyoto City's Ohki High School, from 1948 to 1951. In March 1945, military requisi- tion of the Kawanabe property, which was situated in downtown Kyoto, and the subsequent demolition of the family home necessitated the tearful and hasty removal of only a fraction of the family's be- longings in a cart (HK 490; numbers refer to the subsequent 'Lifetime list of publications by Hiroya Kawanabe'). He and his mother were able to save only a portion of his father's books; his passion for reading may be due to the influence of his father. Interestingly enough, during his junior high school and high school years, Kawanabe tried to improve the method used to catalogue the books in his school libraries, though he subsequently learned Figure 1.Hiroya Kawanabe during his convocation address on that the NDC (Nihon Decimal Classification) was the occassion of receiving Doctor of Science honoris causa at the the most convenient cataloguing method in com- University of Guelph, 5 October 1995. Photograph by M. mon use. Schwalbe.

Metamorphosis and the transition from larvae or embryos to juveniles in fishes are important in order to answer, for example, questions about: (1) life-history styles and their modifications in evolutionary perspective and within current environmental demands; (2) the development and application of fisheries recruitment models, (3) the use of ontogenetic scales for interspecific comparisons, (4) the identification of ontogenetic shifts in resource use, and (5) the discovery of evolutionary interrelationships of species or genera. This volume is dedicated to recent studies and reviews of existing knowledge on this insufficiently-addressed area of ichthyology. Most of the papers in this volume were presented in Bratislava, Slovakia, at the 1st International Workshop of the Fish Ontogeny Network of Europe (FONE) in September 1997, a meeting sponsored in part by the European Commission. This volume emphasizes an integrated approach to the study of fish ontogeny, which is a process during which one event is related to another and everything is related to everything else, encompassing physiology, morphology, behaviour and niche.Within this comprehensive perspective, the papers in this volume are grouped along four major themes: reflections on early ontogeny and metamorphosis, organism-environment relationships, ontogeny of predator-prey interactions, and behaviour and ontogeny. Among other issues, the papers consider topics such as whether one can identify when fish metamorphosis ends, whether the larva period begins with hatching or with the onset of exogenous feeding, whether fish ontogeny is 'saltatory' or 'gradual', and whether larvae are eliminated in some fishes with direct development. The keynote paper of this volume reviews the main topics within contemporary paradigms and the final paper concludes that the onset of the juvenile period can be identified in some species, but precision remains problematic, emphasizing the need for further research in this dynamic area of fish biology.

The elasmobranch fishes include the living sharks, skates and rays that are important members of nearly all marine ecosystems. Their large size, secretive behavior, and wide-ranging habits make them difficult to observe in the field or to maintain in captivity. Consequently, little is known about their natural behavior and how it is mediated by their sensory systems. This volume is dedicated to the scientific contributions and memory of Donald Nelson, a pioneer in the study of shark behavior, sensory biology, and remote instrumentation. The two opening papers review Don Nelson's unique scientific accomplishments and provide insight into his strong bias towards study of animals in the field. These are followed by 14 scientific papers on elasmobranch behavior, sensory biology, and current monitoring technologies. The papers on elasmobranch sensory biology and behavior address questions on hearing, the lateral line, electroreception, the brain, orientation behavior, chemical irritants, feeding, and reproduction. The latter section of the volume presents papers on conventional tagging techniques, ultrasonic telemetry, physiological telemetry, remote monitoring techniques, archival tagging and satellite tagging. The intent of this volume is to familiarize both new and established scientists with the sensory biology and behavior of sharks and rays, and to encourage further behavioral research on these animals in their natural environment.

Hypogean (cave, artesian) fishes have fascinated researchers even before they were described in the scientific literature in 1842. Since then, a number of scientists have used them to justify their own evolutionary ideas, from neo-Lamarckism to neo-Darwinism, from neutral evolution to selectionist approaches. Research in recent years has shown that these fishes are much more complex in their adaptations to the subterranean environment than previously believed: there are those with features expected from living in total darkness (complete blindness and depigmentation) and poor in nutrients (extremely low metabolic rates); others differ very little, if any, from their epigean (surface) ancestors in their morphology and physiology (but not so in their behavior). Some of them even live in nutrient-rich environments. Actually, one of the most overlooked facets of these animals is that there are more species of hypogean fishes without troglomorphisms (blindness, depigmentation) than with troglomorphic ones. The study of these apparently `unadapted' fishes is providing new insights into our understanding of the evolution of phenotypic characters, founding effect, behavioral, and physiological adaptations. The 86 species of troglomorphic fishes described so far belong to 18 different families, many of which would hardly fit the notion that they were 'preadapted' to conquer the underground environment. Further, many troglomorphic `species' show very little genotypic differentiation when compared with their putative ancestors, indicating that massive phenotype changes can be achieved via little genetic reorganization, a reorganization that mostly affects regulatory genes. These and many other topics are discussed in this volume containing 29 papers, written by 41 authors from 9 countries. Hopefully, this volume will convince many other researchers that hypogean fishes represent a unique opportunity to study a concept in evolutionary biology that is only superficially understood: convergent evolution.

Salvelinus species are one of the most thoroughly studied groups of fishes. Many reasons explain this intense interest in charr biology. Charrs have a Holarctic distribution encompassing many Asian, North American, and European countries and occupy diverse marine and freshwater environments. Furthermore, the current distribution of charr includes areas that were directly influenced by climate and topographic change associated with the many Pleistocene glaciations. Undoubtedly, these conditions have promoted much of the tremendous morphological, ecological, and genetic variability and plasticity within Salvelinus species and they make charr very good models to study evolutionary processes 'in action'. Many charr species also exhibit demographic characteristics such as slow growth, late maturity, and life in extreme environments, that may increase their susceptibility to extinction from habitat changes and overexploitation, especially in depauperate aquatic habitats. This vulnerability makes understanding their biology of great relevance to biodiversity and conservation. Finally, charr are of great cultural, commercial, and recreational significance to many communities, and their intimate linkage with human societies has stimulated much interest in this enigmatic genus. This volume comprises a selection of papers presented at the fourth International Charr Symposium held in Trois-Rivières (Québec, Canada), from 26 June to 1 July 2000. It includes 31 papers on ecological interactions and behaviour, trophic polymorphism, movement and migration, ecophysiology and evolutionary genetics, ecological parasitology, environmental stress and conservation. These studies cannot cover all recent developments in the ecology, behaviour and conservation of Salvelinus species, but collecting them into a special volume should bring attention to current research on this important genus and stimulate further work onSalvelinus species.

This book is the first complete biography of one of the founders of fishery science, William Edwin (Bill) Ricker (1908 - 2001). Bill is immortalized in the Ricker Curve. He developed the Curve in his studies of stock and recruitment in fisheries, but it has been widely applied in many areas of science. Bill is best known for his contributions to fishery science, but he was also internationally recognized as an entomologist and a scientific editor. This book combines Bill’s own recollections with contributions from those who knew him and worked with him as a colleague during his multifaceted career. In an article written shortly before his death, Bill gives his own account of his career and intellectual development. A complete bibliography of Bill’s scientific publications, translations and manuscripts has been compiled by his son Karl, and accompanies this article. Karl has also written a detailed account of Bill’s early education and his accomplishments in botany and ornithology. Geoff Scudder summarizes Bill’s contributions to entomology, Jon Schnute provides both personal and professional insights into Bill’s mathematical accomplishments, and Dick Beamish and Don Noakes present personal recollections of Bill as a scientist and colleague.

Over the last few years there have been advances in the quantitative study of age and growth of chondrichthyan fishes. Novel approaches to ageing of various chondrichthyan fishes continue to arise. This volume is a collection of papers on several of these topics that include new hard parts (e.g. caudal thorns) for assessments of age, new techniques for validation (e.g. bomb radiocarbon) and reexaminations of previous age and growth models. This volume also contains papers on the importance of assessing the precision and accuracy of statistical formulas, analyses, and models that are used in age and growth studies. There is currently a great deal of research being conducted, some of which is truly "pushing the envelope," in attempts to assess the life history parameters of numerous chondrichthyan fishes.