Abstract
ABSTRACT The seasonal variation of the locomotor activity rhythm of Talitrus saltator was investigated in a population from the supra-littoral zone of the new harbour beach of Ghar El Melh. The rhythm was recorded in individual animals over the four seasons under two simultaneous experimental regimens: the natural light/dark cycle and the continuous darkness. Results revealed that, whatever the season, actograms and mean activity curves showed globally that individuals of T. saltator concentrated their activity during the experimental and subjective day. In addition, specimens exhibited a nocturnal circadian rhythm of locomotor activity with an ultradian component. Under light–dark cycle, circadian periods determined by periodogram analysis in four seasons were appreciably similar and were close to 24 h. Under constant darkness, the circadian period was longer in the autumn (τDD = 1501ʹ.81 ± 56ʹ.2) than the other seasons. In addition, the study of the mean activity times calculated for four seasons showed that the most important activity of individuals was observed in the spring and the autumn under entraining and free-running conditions, respectively.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
