|Recruitment in marine fishes: is it regulated by starvation and predation in the egg and larval stages?|
Leggett, W.C.; Deblois, E. (1994). Recruitment in marine fishes: is it regulated by starvation and predation in the egg and larval stages? Neth. J. Sea Res. 32(2): 119-134
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579, more
|Authors|| || Top |
- Leggett, W.C.
- Deblois, E.
We used literature reports to evaluate the hypotheses that: 1. year-class strength in marine fishes is determined by mortality operating during the pre-juvenile stage of the life history, and 2. recruitment in marine fishes can be regulated by starvation and predation in the egg and larval stages. The available evidence is largely consistent with the first hypothesis, although mortality operating during the juvenile and post-juvenile stage may moderate the variation induced at the pre-juvenile stage. The hypothesis that recruitment can be regulated by starvation during the larval stage was assessed in relation to Hjort's 'critical period' and Cushing's 'match-mismatch' hypotheses. The available evidence does not support a major link between food abundance at the time of first feeding, and recruitment (Hjort's 'critical period'). The hypothesized relationship between recruitment and the coincidence between the seasonal timing of plankton production and the seasonal abundance of larvae (Cushing's 'match-mismatch') is generally supported. However, the relationships are weak and the importance of the strength of the coupling between seasonal cycles in plankton and larval abundance appears to be weaker than had previously been surmised. Recent evidence, which suggests that failure to distinguish between food abundance in the environment and the availability of food to individual larvae may have compromised the evaluation of these hypotheses, is reviewed. The relationship between mortality due to predation and its potential effects on recruitment was evaluated with reference to two emerging paradigms, the 'bigger is better' and the 'stage duration' hypotheses. We conclude that failure to fully evaluate the assumptions underlying these hypotheses may have led to erroneous generalizations regarding the importance of size at age/stage and growth rate on the probability of death due to predation. Neither the 'bigger is better', nor the 'stage duration' hypotheses is unequivocally supported.