|Zooplankton response to a warmer northern Wadden Sea|
Martens, P.; van Beusekom, J.E.E. (2008). Zooplankton response to a warmer northern Wadden Sea. Helgol. Mar. Res. 62(1): 67-75
In: Helgoland Marine Research. Springer: Berlin; Heidelberg. ISSN 1438-387X, more
Long-term changes; Temperature; Zooplankton; Copepoda [WoRMS]; Oithona Baird, 1843 [WoRMS]; Marine
Weekly measurements of mesozooplankton (>76 µm) and hydrographic parameters have been carried out since 1984 in the List Tidal Basin (northern Wadden Sea). Monthly water temperature signiWcantly increased by 0.04°C year¡1. The largest increase by 3°C in 22 years occurred in September, implying an extension of the warm summer period. Mean annual copepod abundance and length of copepod season correlated signiWcantly with mean temperature from January to May. Except for an increasing Acartia sp. abundance during spring (April-May), no longterm trends in copepod abundance were observed. The percentage of carnivorous zooplankton increased significantly since 1984 mainly due to a sudden increase in the cyclopoid copepod Oithona similis in 1997. We expect that global warming will lead to a longer copepod season and higher copepod abundances in the northern Wadden Sea.
- Long-term monitoring of zooplankton at Sylt Island, more