Changes in abundance and species composition of neritic pelagic fish stocks in connection with larval mortality caused by cannibalism and predatory loss by carnivorous plankton

There have been numberous phenomena recorded characterized by large changes in abundance and species composition of neritic pelagic resources in many parts of the worlds oceans, but a reasonable explanation has not been made so far. A working hypothesis is proposed on the role of several important ecological characteristics which are genetically inherent to each species, in the change in stock abundance and accordingly change in species composition. Larval mortality by cannibalism and by predation by carnivorous plankton is discussed in detail. A mathematical model based on the hypothesis is outlined which describes the change in the number of fish in a given cohort throughout their life span.