Often a professionally organized criminal activity
IUU fishing respects neither national boundaries nor international attempts to manage fishing on the high seas
It puts incredible pressure on fish stocks and significantly distorts global markets.
Worth between US$10 -23.5 billion per year, it also presents a major loss of income to coastal countries and coummunities. This is especially the case for some of the world's poorest countries, which depend on fishing for food, livelihoods and revenues.
The poachers are also killing tens of thousands of marine animals as bycatch
and destroying delicate habitats through their unregulated use of damaging, and sometimes illegal, fishing practices
Flags of convenience
The biggest problem for fisheries management and the fight against IUU fishing are so-called flags of convenience (FoC).
Under existing laws governing the high seas
, the law of the flag state - the country in which a vessel is registered - applies. So if a country either hasn't signed up to fishing agreements or doesn't enforce them, then vessels flagged to that country are able to plunder the high seas, and even other nations' waters, at will.
One industry source estimates that 1,300 fishing vessels of significant size are flying flags of convenience.