Differences in behavioral responses of Eurytemora affinis (Copepoda, Calanoida) adults to salinity variations

• Published in: Journal of Plankton Research
• Language: English
• Published: Oxford University Press 2011
• Subjects: Life Sciences; sami; Copepods
• Online Access: http://hdl.handle.net/2262/50419; https://doi.org/10.1093/plankt/FBQ006

Abstract Estuarine copepods undergo strong and frequent salinity variations caused by alternating tides. Salinity is known to be a major parameter in the ecology of copepods from brackish waters but its effects on small scale behavior are relatively unclear. In this study we used 2-dimensional laboratory filming techniques to record swimming paths of the three reproductive stages (i.e. male, non-ovigerous female and ovigerous female) of E. affinis from the Seine estuary, under different salinity conditions. We showed that the probability density of both the instantaneous swimming speed and the duration of the two most frequent swimming states (i.e. break and slow swimming) followed a power-law trend regardless of the salinity. Increase in salinity (i.e. 5, 15, 25 and 30) steadily decreased the instantaneous speed of E. affinis reproductive stages. At the extreme salinity of 0.5, the mean speed decreased for non-ovigerous females and ovigerous females but increased for males, when compared to higher salinities. Maximum speed was observed at salinity 0.5 for males and at salinity 5 for non-ovigerous females and ovigerous females. Low swimming speeds were associated with break events of high frequency and long duration. High swimming speeds were exhibited with cruising states of high frequency and break events of short duration. This supports laboratory and field studies indicating a preference of E. affinis for low to medium salinities. : Souissi, Sami, [e-mail] merged with this user on 15-Jul-2009 by Stader, Lulu (Souissi, Sami) [e-mail] (Michalec, Francois Gael) [e-mail] (Souissi, Sami) [e-mail] (Dur, Gael) [e-mail] (Mahjoub, Mohamed Sofiene) [e-mail] (Schmitt, Francois) [e-mail] (Hwang, Jiang-Shiou) National Taiwan Ocean University, Institute of Marine Biology, Zooplankton and Coral Reef Laboratory - Keelung - TAIWAN, PROVINCE OF CHINA (Michalec, Francois Gael) U.S.T.L., Station Marine de Wimereux- UMR CNRS 8187 LOG - 28 Avenue Foch--> - 62930 - Wimereux - FRANCE (Souissi, Sami) U.S.T.L., Station Marine de Wimereux- UMR CNRS 8187 LOG - Wimereux - FRANCE (Dur, Gael) National Taiwan Ocean University, Institute of Marine Biology, Zooplankton and Coral Reef Laboratory - Keelung - TAIWAN, PROVINCE OF CHINA (Dur, Gael) U.S.T.L., Station Marine de Wimereux- UMR CNRS 8187 LOG - Wimereux - FRANCE (Mahjoub, Mohamed Sofiene) National Taiwan Ocean University, Institute of Marine Biology, Zooplankton and Coral Reef Laboratory - Keelung - TAIWAN, PROVINCE OF CHINA (Mahjoub, Mohamed Sofiene) CNRS, Laboratory of Oceanology and Geosciences - Wimereux - FRANCE (Schmitt, Francois) - FRANCE (Schmitt, Francois) National Taiwan Ocean University, Institute of Marine Biology - Keelung - TAIWAN, PROVINCE OF CHINA (Hwang, Jiang-Shiou) - TAIWAN, PROVINCE OF CHINA (Hwang, Jiang-Shiou) FRANCE TAIWAN, PROVINCE OF CHINA