Endogenous rhythm in activity of an estuarine amphipod, Talorchestia longicornis


Journal Article

The biological rhythm in activity of the supratidal amphipod Talorchestia longicornis Say was determined under constant conditions. Surface activity was monitored with a time-lapse video system under red light and assessed as the number of animals emerging from their burrows and active on a sand substrate at 0.5 h intervals. The amphipods had a circadian rhythm in which they were active at the time of night at the collection site. The rhythm could be entrained by a light : dark cycle and had an average free-running period of 23.7 h. Activity also appeared to be related to tidal times at the collection site because, under constant conditions, surface activity was suppressed at the time of nocturnal high tide and increased at the time of nocturnal low tide. The rhythm is functionally significant for foraging at night to avoid visual predators, desiccation and high temperatures.

Full Text

Duke Authors

Cited Authors

  • Forward, RB; Wyatt, L; Clifford, D; Barbour, A

Published Date

  • June 1, 2007

Published In

Volume / Issue

  • 40 / 2

Start / End Page

  • 133 - 140

Electronic International Standard Serial Number (EISSN)

  • 1029-0362

International Standard Serial Number (ISSN)

  • 1023-6244

Digital Object Identifier (DOI)

  • 10.1080/10236240701443258

Citation Source

  • Scopus