Periodic variation in the photic behaviour of the Tench (Tinca Tinca L.) in self‐regulating conditions

Abstract

Four series of experiments were performed on Tinca tinca, using a simple instrumental technique, in which the fish could regulate its own activity and rest periods as a function of its light tolerance. A fifth series was performed in LL:35 Lx. In self‐regulating conditions, the illumination levels used were 10, 20, 35 and 100 Lx. Results show a great variability between individuals. The optimum time regulation occurs for 20 Lx and 35 Lx and shows a rhythmic distribution. The suitability of the technique for the study of rhythms in Teleosts is discussed.

Abstracting keywords:

• Photic behaviour
• Tench
• Tinca tinca L.
• self‐regulating conditions

Notes

Centre de Psychologie Expérimental et Comparée, Univ. de Louvain, Pellenberg, Louvain, Belgium.