Pontius,
Trained eyes on boats are sure to be useful, but fishing boats aren't as common as they once were.
On the other hand, space-based assets for looking at the sea are more common than they once were. The need for patrols and eyes to seek things out may have abated in the last few decades, as has the number of things to seek out.
Although... what is to be done promptly about any things that are found in the absence of any MPAs?