Larval Size and Recruitment Mechanisms in Fishes: Toward a Conceptual Framework

Abstract

Understanding the mechanisms controlling recruitment in fishes is a major problem in fisheries science. Although the literature on recruitment mechanisms is large and growing rapidly, it is primarily species specific. There is no conceptual framework to integrate the existing information on larval fish ecology and its relationship to survival and recruitment. In this paper, we propose an integrating framework based on body size. Although all larval fish are small relative to adult fish, total length at hatching differs among species by an order of magnitude. As many of the factors critical to larval survival and growth are size dependent, substantially different expectations arise about which mechanisms might be most important to recruitment success. We examined the evidence for the importance of size to feeding and starvation, to activity and searching ability, and to risk of predation. Regressions based on data from 72 species of marine and freshwater species suggest that body size is an important factor that unifies many of the published observations. A conceptual framework based on body size has the potential to provide a useful integration of the available data on larval growth and survival and a focus for future studies of recruitment dynamics.

Patterns of resource use by fishes and macroinvertebrates in Barataria Bay, Louisiana

“…Both density-dependent and stochastic causes can work simultaneously on recruitment for a given population (Jobling 1995), but without the appropriate environmental conditions for a life history stage, there is limited opportunity for density-dependent effects to influence recruitment to the next life history stage. The focus of research in recruitment has changed from stock-recruitment models to studies of underlying mechanisms and processes that control year-to-year recruitment variability (Houde 1987, Miller et al 1988, 1991, Miller 1994. Variables including the effects of adult condition on breeding success, effects of food supply on growth and survival of larvae, predation effects on early life stages, abiotic variables, quantity and quality of habitat and the effects of latitude and climate change on these variables are often examined as possible causes of variability in recruitment (Hjort 1914, Cushing 1973, Miller 1994, Jobling 1995.…”

Validation of the first annual increment deposition in the otoliths of European anchovy in the Bay of Biscay based on otolith microstructure analysis

“…Several studies have reported a size-dependent vulnerability to predation (i.e. smaller individuals are more susceptible to predators and experience a higher mortality rate than larger individuals; Miller et al 1988;Rice et al 1993;Sogard 1997). Therefore, the absence of predators could also explain the observed differences in length, because the smallest individuals were not removed from the sea cage.…”

Critical periods and growth-dependent survival of larvae of an estuarine fish, the rainbow smelt Osmerus mordax

“…Size-selective or growth-dependent mortality is frequently interpreted in terms of predation through the 'bigger is better' hypothesis (Miller et al 1988), or the 'stage-duration' hypothesis (Anderson 1988, Cushing 1990, respectively. In the present study, predation seemed to be of little importance in the ETM, thus the significance of larval body size is different.…”

“…For instance, if survival is governed by predation, larger larvae should be less susceptible to predation (the 'bigger is better' hypothesis; Miller et al 1988), while faster-growing larvae should be available to predators for a shorter period of time before metamorphosis to the juvenile stage (the 'stage duration' hypothesis; Anderson 1988, Cushing 1990). In the case where starvation is the principal cause of mortality, larger and faster-growing larvae are expected to exhibit the highest feeding rates, and to be less sensitive to starvation (Beyer & Laurence 1980, Rosenberg & Haugen 1982.…”

“…9) indicated that larvae up to 30 d of age captured within and downstream of the ETM exhibited similar growth trajectories, but after this age, growth rate decreased in larvae captured downstream of the ETM. This suggests that the latter larvae exploited the ETM during a major part of their early life but were expulsed and experienced poorer growth conditions during the latter part of the summer.Size-selective or growth-dependent mortality is frequently interpreted in terms of predation through the 'bigger is better' hypothesis (Miller et al 1988), or the 'stage-duration' hypothesis (Anderson 1988, Cushing 1990, respectively. In the present study, predation seemed to be of little importance in the ETM, thus the significance of larval body size is different.…”