Time to learn the life history of fish

The collapse and lack of recovery of commercially exploited marine organisms worldwide has served to challenge the credo that single-species models, catch and abundance data, and metrics of individual growth are sufficient to assess the status of harvested fishes and invertebrates. One also requires knowledge of the behaviour, life history and habitat of targeted species, of those caught incidentally and of those with whom the harvested species interact.

The aim of this book is to provide a broad understanding of the biological, economic and social aspects of fisheries. In this respect the authors succeed marvellously. However, it is their emphasis on life histories (stage - and age-specific patterns of mortality and reproduction) and ecology that distinguishes this fisheries textbook. Life histories determine a population's ability to sustain various levels of fishing and to recover from collapse. By emphasising ecology, the authors underscore the often-overlooked point that the effects of fishing on the persistence of marine organisms are not independent of life history, habitat quality, interactions with other species and stochastic changes to the physical environment.

Among the book's 17 chapters are several that will prove exceedingly useful. From the traditional fisheries science perspective, these range from the excellent line drawings and summary tables of harvested species and fishing gear to the clear treatments of stock-recruitment relationships, single and multi-species population analyses, and bio-economic modelling. From the ecological perspective, chapters addressing life histories, density-dependent habitat selection, effects of fishing on incidentally harvested species and their habitats, and ecosystem modelling should be required reading for undergraduates and postgraduates in marine ecology and fisheries science.

Distractions include the unhelpful characterisation of life histories as fast and slow, confusion over the terms "response" and "recovery" when describing changes to fished benthic systems, and the unsupported assertion that intrinsic rates of increase in birds and mammals are notably low.

One is left with the conclusion that a comprehensive understanding of the life histories and basic ecology of targeted and incidentally harvested species should be ensconced in the research programmes and educational curriculums of present and future fisheries scientists, resource managers and marine conservation biologists. Jennings et al have provided a primer without equal.

Jeffrey A. Hutchings is associate professor of biology, Dalhousie University, Canada.