Zooplankton communities are important for marine ecosystem functioning, and are traditionally sampled using plankton nets. These nets however can destroy fragile organisms and have limited spatio-temporal coverage. The Video Plankton Recorder (VPR) provides an alternative technique for the assessment of zooplankton. It is an underwater camera that records in situ images of organisms without damaging them. This study compared the traditional WP2 net and the VPR sampling technique and evaluated their feasibility, benefits and challenges for zooplankton studies in the Belgian part of the North Sea (BPNS). Both sampling techniques provided similar data on zooplankton community composition, although density estimates were considerably lower for the VPR data. Factors that potentially contributed to these underestimates were the high turbidity in the BPNS and the low magnification settings of the VPR. Higher relative abundances were observed for gelatinous taxa in the VPR data, indicating that the VPR technique could be beneficial for the observation of fragile and gelatinous taxa. The WP2 technique on the other hand is preferred for long-term monitoring programs, as data collection is faster, cheaper and easier to standardise. Additional research is recommended to assess the consistency of the results of this study over space and time in the BPNS.
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