Preliminary Results on the Daily and Seasonal Rhythms of Cuttlefish Sepia officinalis (Linnaeus, 1758) Locomotor Activity in Captivity

This research was aimed at characterizing the daily rhythms of locomotor activity of cuttlefish Sepia officinalis (Linnaeus, 1758), a promising aquaculture species, in a captive environment. Cuttlefish were distributed within two tanks equipped with infrared photocells, allowing the monitoring of locomotor activity continuously from August to February. Results showed a preference of cuttlefish for being active during the night in summer (24.2± 1.3 ◦C) and in autumn (18.4± 3.4 ◦C), with maximum activity peaks observed, respectively, at 01:09 h and 21:47 h, in close relation with sunset time. In winter (12.7 ± 1.4 ◦C), this preference changed, with higher levels of activity observed during the afternoon in December (15:20 h) and in January (18:13 h), thus suggesting this species as possessing a dualistic behaviour. Levels of activity progressively decreased during autumn and winter, likely related to low temperatures. The present study offers new insights on the behaviour of Sepia officinalis, presenting a variability of patterns across seasons, regulated by environmental synchronizers; photoperiod determining the activity periods, and temperature modulating the levels of activity. Such information may be a valuable tool for the improvement of cuttlefish culture protocols in aquaculture, and consequently its welfare.