We've done research on that very issue. I fully agree with you that the situation is dire in much of the high seas. However, we have a new tool to globally monitor our fisheries worldwide. We wrote a paper in Science on this last year called “Ending hide and seek at sea”. The tool is called an automatic identification system, which allows us to track fishing vessels in real time and see foreign overfishing in distant waters, for example, off West Africa.
On May 18th, 2017. See this statement in context.