Illegal, unreported and unregulated fishing (IUU fishing for short) is one of the greatest threats to the sustainability of fishing, marine ecosystems, marine biodiversity, and human food security. Although international bodies and the UN regard illegal fishing as an environmental crime and the European Union has adopted a regulation to combat IUU fishing the problem has not been fully resolved because there are still gaps and loopholes.
Illegal, undocumented and unregulated fishing, also known as pirate fishing, has many facets. In deep-sea fishing, it is understood to mean all types of commercial fishing carried out without the necessary licence, in which the fishing quota authorised under the fishing licence is exceeded, or in which the quantities caught are not, not completely or incorrectly documented. However, it is also considered to be IUU fishing if a fishing vessel fishes in territorial waters of other nations without permission, or if it violates the fishing laws of that country, for example by ignoring fishing times and protected areas. The territorial waters of some West African countries, for example, are among the preferred fishing areas for pirate fishing. In none of these countries is there a strong fisheries control authority, so that the pirate vessels are not in much danger of being caught.
A number of institutions are involved in deciding how much fish can be harvested from the sea
Fishing quotas have an immediate impact on the players in the fisheries sector and the release of the numbers is closely watched by all concerned. The route by which raw data is converted into the precise figures that are published as fishing quotas is long, with inputs from several institutions, and gives an idea of the enormous significance attached to these numbers.
Fish, individually or in swarms, can usually be found in places offering them the best for their lives: where they find food, where it is safe to reproduce and survive as species. Such preferences, together with environmental conditions, may vary from year to year, and hence the number of fish coming together may vary as well. Fishermen know where to find the fish and are familiar with annual fluctuations. Fishing grounds, when seen as fish habitats, do not feature national borders, whereas fishing vessels carry the flags of their home ports. Fish stocks which are international by nature thus have national owners when turned into catches. The subsets of these fishable stocks allocated to and harvested by sovereign states are called fishing quotas.