The populations of 37 characteristic species of fish and benthic animals in the Eastern Scheldt have decreased by an average of 28% since 1994. 15 of these species are decreasing in number, such as plaice, mussels, and European lobster, while 8 species (including purple snail and flat oyster) are increasing. This is evident from analyses by CBS based on data from the Monitoring Project Underwater Shore (MOO) of Stichting ANEMOON.

The Eastern Scheldt has a unique biodiversity and is designated as a European protected habitat of the type ‘large, shallow bays and inlets’. The dikes along the Eastern Scheldt have been strengthened with basalt blocks. Many animal species, such as sea anemones, crustaceans, and shellfish, live on or between these stones. Many fish species seek food or lay eggs there.

Decline of 15 Species of Fish and Benthic Animals, 8 Species Are Increasing

The condition of the underwater nature of the Eastern Scheldt is monitored based on 37 characteristic species. This includes fish, and attached and crawling benthic animals, such as sea squirts, starfish, crustaceans, mollusks, worms, sea anemones, and jellyfish. These species are largely dependent on the artificial underwater rocky coast of the Eastern Scheldt.

Of the 8 species, the trend is increasing; the populations of 15 species are declining. 10 species are stable, and 4 species have an uncertain trend.

Furthermore, the decline of fish is partly related to increasing temperatures of the Eastern Scheldt water in the summer. Fish are therefore increasingly moving to deeper (colder) parts of the North Sea.