Opportunistic utilization of mysid shoals by surf-zone teleosts
In: Marine Ecology Progress Series. Inter-Research: Oldendorf/Luhe. ISSN 0171-8630; e-ISSN 1616-1599, more
| |
Abstract |
The utilization of dense concentrations of the mysid Mesopodopsis slabberi by nearshore teleosts associated with a surf-exposed sandy beach in southern Africa was investigated during a 24 h study. Five species, namely Lithognathus mormyrus, Liza richardsoni, Monodactylus falciformis, Pomadasys olivaceum and Sphyraena africana, fed extensively on this resource. Mysids also featured in the diets of the other teleosts examined. Foraging activity did not appear to coincide with periods of increased prey availability. This may be a reflection of the patchy distribution of both predators and prey or, alternatively, it may indicate that mysids were consumed outside the beach/surf-zone system. Temporal differences in habitat occupancy probably reduce the likelihood of interspecific competition over food. Comparison of the mean contribution of mysids to the diet estimated during this 24 h study with that obtained from long-term studies suggests that the dietary importance of highly motile prey items such as mysids may, in the past, have been overlooked. Opportunistic utilization of superabundant prey items, when readily available, may be of immense importance to teleosts frequenting highly dynamic environments. |
|