Laboratory entrainment of the rhythmic swimming activity of corophium volutator to cycles of temperature and periodic inundation

Holmstrom, W. F.; Morgan, E.

The tidal rhythm of swimming activity shown by the estuarine amphipod C. volutator can be entrained to cycles of temperature and immersion in the laboratory. The rhythm is phased to the period of increasing temperature, or to the time at which the animals are wetted by the artificial tide, and the activity maxima follow the zeitgeber with a phase delay of about 5-6 h in each case. Entrainment to these variables alone is inadequate to account for ebb tide swimming in the natural state, and it is likely that the rhythm is normally entrained by a number of factors of variable significance.