Voorstel voor monitoring van zoöplankton in de Noordzee: monitoringplan zoöplankton MONS ID14

In this report, a draft plan for monitoring and supporting research of zooplankton in the Dutch part of the North Sea has been drawn up. The aim is to draw up a zooplankton monitoring plan that can provide answers to the following questions in due course: What is the composition and distribution of zooplankton in space and time? And also: what are the trends (years and decades) (in composition and distribution of zooplankton in space and time) and what are the effects of new human use? The results from the monitoring should enable to understand and predict changes in zooplankton in the North Sea, so that validated scenario studies can be performed. All this in order to be able to assess the ecological capacity and the effects of individual and cumulative use thereon. The monitoring plan consists of two phases, a 1-year inventory study and a 4-year monitoring to test whether the results can be used to answer the questions. First of all, an overview was drawn up of the available knowledge about the policy frameworks and goals for zooplankton monitoring, an overview was given of monitoring activities in the Netherlands and other North Sea countries and a description was made of conventional and innovative techniques that are used for zooplankton monitoring. Internationally (e.g. OSPAR) the focus is currently mainly on indicators that indicate the role of zooplankton in the food chain. The density and size distribution of the mesozooplankton (0.2 – 20 mm) is used as an indicator for the food availability of fish. Biodiversity is also important. These indicators can be measured in different ways. In addition to classical methods, in which net samples are analyzed under the microscope, more and more innovative methods are being used. Phase 1: The plan for the first phase concerns a 1-year study aimed at determining the required resolution for identifying trends in space and time and the feasibility of innovative techniques to be used in the monitoring of zooplankton. The plan includes which classical and innovative techniques can be used and how these can contribute to answering the knowledge questions. This concerns the collection of zooplankton with net samples and the analysis thereof, such as by means of microscopy, image analysis or DNA metabarcoding, and the application of in situ techniques, such as dragging a video plankton recorder, acoustic measurements and the use of scanners. Three sailing trips have been proposed for this and measurements at fixed measuring stations. Phase 2: The plan for phase 2 is still surrounded by uncertainties, because it is being implemented on the basis of the findings of phase 1. In this project, only a preliminary plan can be drawn up for a 4- year program and budgeted on the basis of the number of measurement locations and times. These will be smaller compared to the monitoring of phase 1. It is also unclear at the start of phase 2 which techniques will ultimately be selected, so that a specification must also be made for this.