Influence of temperature on daily locomotor activity in the crab Uca pugilator

• Published in: PLOS ONE
• Main Authors: Mat, Audrey M., Dunster, Gideon P., Sbragaglia, Valerio, Aguzzi, Jacopo, Iglesia, Horacio O., de La
• Other Authors: University of Washington Seattle, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Marine Sciences / Institut de Ciències del Mar Barcelona (ICM), Consejo Superior de Investigaciones Cientificas = Spanish National Research Council (CSIC), Centro de Investigaciones Biológicas (CSIC), Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: ACL; carcinus-maenas; oyster crassostrea-gigas; behavior; responses; circadian-rhythms; diurnality; margins; sand fiddler-crabs; search; temporal niche; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Crassostrea gigas
• Online Access: https://hal.science/hal-02612002; https://hal.science/hal-02612002/document; https://hal.science/hal-02612002/file/Mat_etal_POne_2017.pdf; https://doi.org/10.1371/journal.pone.0175403

WOS:000400309200019 International audience Animals living in the intertidal zone are exposed to prominent temperature changes. To cope with the energetic demands of environmental thermal challenges, ectotherms rely mainly on behavioral responses, which may change depending on the time of the day and seasonally. Here, we analyze how temperature shapes crabs' behavior at 2 different times of the year and show that a transition from constant cold (13.5 degrees C) to constant warm (17.5 degrees C) water temperature leads to increased locomotor activity levels throughout the day in fiddler crabs (Uca pugilator) collected during the summer. In contrast, the same transition in environmental temperature leads to a decrease in the amplitude of the daily locomotor activity rhythm in crabs collected during the winter. In other words, colder temperatures during the cold season favor a more prominent diurnal behavior. We interpret this winter-summer difference in the response of daily locomotor activity to temperature changes within the framework of the circadian thermoenergetics hypothesis, which predicts that a less favorable energetic balance would promote a more diurnal activity pattern. During the winter, when the energetic balance is likely less favorable, crabs would save energy by being more active during the expected high-temperature phase of the day-light phase-and less during the expected low-temperature phase of the day-dark phase. Our results suggest that endogenous rhythms in intertidal ectotherms generate adaptive behavioral programs to cope with thermoregulatory demands of the intertidal habitat.