Wadden Sea Fish
With 162 known species (Berg et al. 1996) the fish community of the Wadden Sea, including the North Sea and inflowing rivers, is exceptionally diverse. Most fish in the Wadden Sea are marine species, which spend most of their time in the sea. Some fish species spend most of their time in the Wadden Sea, others pass by on their migration route. Also, diadromous species start their life in freshwater environments, spend their adult life in the sea and return to freshwater to spawn. Some species use seagrass beds, saltmarshes or others of the multiple habitats as a nursery ground, using and coping with the dynamic conditions of this dynamic environment, formed by wind, waves and tides.
The populations of many fish species in the Wadden Sea have declined in recent decades and the causes of these declines are only partly known or understood. Formerly typical elements of the Wadden Sea fish fauna such as sharks, rays and cod are largely absent, and the nursery function provided for juvenile plaice and sole, both characteristic for the Wadden Sea, has apparently declined. Processes and developments well outside the Wadden Sea can have an impact on the fish fauna in the Wadden Sea.
According to Danish, German and Dutch red lists, there are 17 endangered fish species in the Wadden Sea area: river lamprey, sea lamprey, twaite shad, European eel, North Sea houting, Atlantic salmon, sea stickleback, greater pipefish, snack pipefish, greater weever, poor cod, transparent goby, picked dogfish, tope shark, starry smooth-hound, common stingray and thornback ray.