Once upon a larva: revisiting the relationship between feeding success and growth in fish larvae

Abstract

Variations in larval fish growth rates are largely the result of variability in biotic and abiotic characteristics of the feeding environment experienced by each individual. An assessment of an individual's overall feeding success (i.e. accumulation of utilizable organic matter) can best be achieved at the time of capture when the relationships among environment, short-term feeding success as defined by gut content and long-term feeding success as defined by accumulated growth can be contrasted. Here, we investigated the relationships between average growth, feeding success, and variability in individual growth and feeding rates across a range of taxa based on a synthesis of studies in which stomach content and otolith growth were measured in the same individuals. Instantaneous measures of feeding success were highly variable and demonstrated a positive yet somewhat limited association with growth rates across all taxa. The strength of the feeding-growth relationships among taxa, and cohorts within taxa, was reflected in the autocorrelation of individual growth rates, suggesting that stable growth was achieved through consistent feeding success. However, when viewed at the individual level, faster growth was achieved in individuals with more variable growth rates, and by inference more variable past feeding success. The dichotomy in these underlying relationships may point to the importance of stochastic events in the development of exceptional individuals in a population, and may be linked to how surplus energy is allocated to individual growth rates. The positive correlation found between feeding success and growth in all taxa is consistent with the growth-survival paradigm for the larval stage of fish. However, both the correlation between feeding success and growth and the serial correlation of growth time-series was greatest in fast-growing species, suggesting that the potential for an early “critical period” regulating survival varies among species, reaching a maximum in fast-growing fish.

Effects of ocean acidification increase embryonic sensitivity to thermal extremes in Atlantic cod, Gadus morhua

“…The regulation of energy allocation to maximize growth during embryogenesis is important for the fitness and survival of hatching larvae because predation pressure during fish early life history is strongly size dependent and generally corresponds with the principle of 'bigger is better' (Houde, 1997;Pepin et al, 2015). Furthermore, reduced body size at hatch affects larval foraging ability and starvation resistance (Miller et al, 1988), thus leading to increased vulnerability throughout the critical first-feeding period, which can be decisive in terms of year-class strength (Chambers & Trippel, 2012).…”

Different key roles of mesoscale oceanographic structures and ocean bathymetry in shaping larval fish distribution pattern: A case study in Sicilian waters in summer 2009

“…The early life history of the fish populations depends on several factors that affect mainly the spawning biomass of fish adults Giannoulaki et al, 2013;Somarakis et al, 2004) and the larval fish conditions (Riveiro et al, 2011), mainly due to feeding success (Pepin et al, 2014), to optimal habitat (Sabatés et al, 2006(Sabatés et al, , 2007Valavanis et al, 2008) and to predation (Litvak & Leggett, 1992;Steele & Forrester, 2002;Yin & Blaxter, 1987). Moreover, mesoscale oceanographic structures including geostrophic and wind influenced current regimes (wind-induced mixing of the surface layer, upwelling) play an important role in determining the patterns of abundance and distribution of larval fish populations.…”

Isotopic discrimination factors and nitrogen turnover rates in reared Atlantic bluefin tuna larvae (<em>Thunnus thynnus</em>): effects of maternal transmission

“…Traditionally, trophic ecology in early life stages of marine fishes has been studied through stomach content analysis (Pepin et al 2014). An alternative approach to understanding early life trophodynamics of larvae without examining gut contents is to estimate the natural content of the stable isotopes of nitrogen and carbon.…”