Bass
Otolith description
The general shape of the otolith is ovally pointed. The sulcus runs straight over of the length of the otolith, with the cauda pointing down. The sulcus is clearly visible and open at the ostium. Ostium and cauda are separated by a narrowing of the sulcus. The ostium is wider and much shorter than the cauda. The surface of the inside and outside is smooth, but can be slightly irregular. The dorsal and posterior margins are slightly lobate. The ventral margin is triangular. The rostrum is well-developed and round, while the antirostrum is small and pointed. There is a small indentation between the rostrum and antirostrum. The posterior margin is rounded and slightly lobate. The inside is convex and the outside concave. The otolith is thin. Otoliths of bass are very large, fish with total length of 50 cm have otoliths of 15 mm.
When eroded the sulcus remains visible. The rostrum and margins are smoothed, but the ventral margin remains triangular.
Otoliths of juveniles are rounder. The sulcus is pointing down at the posterior, but is not as strongly curved as in larger otoliths. The rostrum is more pointed. Otoliths of juvenile bass resemble otoliths of ruffe Gymnocephalus cernuus. The sulcus of ruffe otoliths is wider and straight and the posterior end of the sulcus is not pointing down. Otoliths of ruffe are thicker and more lobate on the margins than are small bass otoliths.
Fish length and distribution
Bass can grow up to 100 cm. Bass is a pelagic schooling, predatory fish (DICELABR.TIF) found in inshore waters. It is occasionally found offshore over rocky grounds or reefs. Spawning takes place from March to June in inshore waters near the British Isles (Wheeler, 1978, Nijssen and De Groot, 1987, Knijn et al., 1993, Muus et al., 1999).
Bass is found in the NE Atlantic and North Sea.
Sample origin
Fyke.