A comparison of food capture and ingestion in juveniles of two flatfish species, Pleuronectes platessa and Limanda limanda (Teleostei: Pleuronectiformes)

Abstract

Juvenile plaice, Pleuronectes platessa (n=6, 151–197 mm SL) and dab Limanda limanda (n=6, 119–180.5 mm SL) feeding on pieces of mussel flesh were studied by high‐speed (200 fields s−1) videophotography at 11) C. Prey capture cycles (involving jaw protrusion and opercular expansion) were described in both species. The capture cycle was followed by at least one cycle (similar to the capture cycle in all respects except food intake) which is believed to transport food to the oesophagus. The transport cycle (or cycles) was followed by a species‐specific number of normal respiratory cycles (7 or 8 in plaice, 11 or 12 in dab) and a final single cycle when food debris was violently ejected from the opercular cavity. The respiratory cycles and ejection cycle cleansed the orobranchial/opercular cavities and gills. Differences between the species were relatively minor, but plaice captured and transported food more quickly than dab.