caa a22 4500 445893729 CHVBK 20180317145624.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s10750-010-0540-0 doi (NATIONALLICENCE)springer-10.1007/s10750-010-0540-0 Seasonal adaptations of Daphnia pulicaria swimming behaviour: the effect of water temperature [Elektronische Daten] [Joshua Ziarek, Ai Nihongi, Takeyoshi Nagai, Marco Uttieri, J. Strickler] Daphnia swimming behaviour is controlled by a variety of external factors, including light, presence of food and predators. Temperature represents a key driver in the dynamics of Daphnia populations, as well as on their motion. In this study, we have investigated the behavioural adaptations of adult Daphnia pulicaria to two different temperatures, representative of the mean winter (3°C) and summer (22°C) temperatures to which these organisms are exposed to in the real environment. Video observations were conducted both in the presence and in the absence of light to investigate possible day/night modifications in the motion strategy. Analyses of mean speed, velocity power spectral density and trajectory fractal dimension point out specific adaptations that allow D. pulicaria to successfully adjust to the changing conditions of the environment. Independently of the light conditions, in cold waters D. pulicaria swim almost vertically with defined motional frequencies, likely to increase the encounter with food items diluted in the fluid. A similar behaviour is displayed by the animals at summertime temperatures in the presence of light; however, in this case the vertical swimming is coupled with the absence of peaks in the power spectra and might be exploited to avoid predators. In contrast, at 22°C in dark conditions D. pulicaria move horizontally with lateral motions to take advantage of possible patches of phytoplankton. This information sheds new light into the complex and dynamic adaptations of D. pulicaria in response to external stimuli. Springer Science+Business Media B.V., 2010 Daphnia pulicaria nationallicence Swimming behaviour nationallicence Temperature nationallicence Adaptation nationallicence Ziarek Joshua Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, 53226, Milwaukee, WI, USA aut Nihongi Ai Great Lakes WATER Institute, University of Wisconsin-Milwaukee, 600 East Greenfield Avenue, 53204, Milwaukee, WI, USA aut Nagai Takeyoshi Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Minato-ku Konan 4-5-7, 108-8477, Tokyo, Japan aut Uttieri Marco Department of Environmental Sciences, University of Naples "Parthenope”, Centro Direzionale di Napoli-Isola C4, 80143, Naples, Italy aut Strickler J. Great Lakes WATER Institute, University of Wisconsin-Milwaukee, 600 East Greenfield Avenue, 53204, Milwaukee, WI, USA aut Hydrobiologia Springer Netherlands 661/1(2011-02-01), 317-327 0018-8158 661:1<317 2011 661 10750 https://doi.org/10.1007/s10750-010-0540-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10750-010-0540-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ziarek Joshua Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, 53226, Milwaukee, WI, USA aut NATIONALLICENCE 700 1- Nihongi Ai Great Lakes WATER Institute, University of Wisconsin-Milwaukee, 600 East Greenfield Avenue, 53204, Milwaukee, WI, USA aut NATIONALLICENCE 700 1- Nagai Takeyoshi Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Minato-ku Konan 4-5-7, 108-8477, Tokyo, Japan aut NATIONALLICENCE 700 1- Uttieri Marco Department of Environmental Sciences, University of Naples "Parthenope”, Centro Direzionale di Napoli-Isola C4, 80143, Naples, Italy aut NATIONALLICENCE 700 1- Strickler J. Great Lakes WATER Institute, University of Wisconsin-Milwaukee, 600 East Greenfield Avenue, 53204, Milwaukee, WI, USA aut NATIONALLICENCE 773 0- Hydrobiologia Springer Netherlands 661/1(2011-02-01), 317-327 0018-8158 661:1<317 2011 661 10750 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer