Fishing has a considerable influence on the ecological quality of the North Sea.

Both commercial and non-commercial fish species, and other organisms, are affected as a consequence (Figure 4). Dutch fisheries account for about 80% of the bottom fishing within the Dutch Exclusive Economic Zone; each year they disrupt the seabed ecosystem in more than 30% of the waters within the 12-mile limit.

Figure 4: The proportion of large fish in catches is falling because large specimens are continually being caught. Fish are adapting by maturing and spawning at a younger age, but this has its limits (Source: RIVO).

In 2002 the North Sea ministers agreed to the designation of a network of protected marine nature reserves in 2010. In June 2003 the ministers of the OSPAR Commission adopted this statement in the Bremen Declaration, paving the way for a legislative basis and creating legal mechanisms for protecting areas of the North Sea important for nature (including the coastline).

The OSPAR Convention for the Protection of the Marine Environment of the North-East Atlantic, replacing the Paris and Oslo conventions, was signed in 1992. It is binding on all the contracting parties (countries). The implementation of the Convention is managed by the OSPAR Commission (OSPARCOM).