Feeding selectivity of juvenile Cape hake Merluccius capensis in the southern Benguela

Abstract

Prey selectivity and feeding behaviour of juvenile shallow-water Cape hake Merluccius capensis are investigated on the basis of material collected at two sites of contrasting feeding regimes in coastal waters off the South African west coast. Hake collected from a site abundant in zooplankton fed preferentially on relatively large crustaceans (amphipods, euphausiids and Pasiphaea semispinosa), but apparently ignored the smaller copepods and translucent prey (chaetognaths), despite these taxa being both numerically and by mass the dominant potential prey items. At a site dominated by recruits of anchovy Engraulis capensis, the hake were almost exclusively piscivorous. Small hake (10–25 cm) migrated vertically into subsurface layers to feed on anchovy, whereas larger fish appeared to remain near the bottom where cannibalism was prevalent. The present observations demonstrate the importance of vertical migratory behaviour in the foraging strategy of juvenile M. capensis.