People who are poor and need to support their family is the most likely if they get hold of the equipment.

However, most fishing companies over fish places. For instance, there is a part of the world with a simple law. The big boats who fish thousands and thousands of creatures stay 10 miles or more away from the shore to give the locals food and support. But the companies have actually been seen within 3 miles of the shore/harbour. (it changes as you travel along I believe)

Unless you are going out with family and friends to catch a few fish, it is pretty likely that your are not overfishing. But anything else you do might well be overfishing because of the simple fact that fish cannot reproduce to our high demand for food, and they are almost fighting a hopeless battle to keep their specie alive.

Let's say a man went fishing with his crew with a boat that can carry 5,000 fish at a time. He fishes the same area with 20,000 fish and goes there every week. Now, the fish may learn the shape of the boat and flee, but he could still wipe out the area, which would force him to leave, go somewhere else, do the same and so on. Corals are also very delicate. If he destroyed them, they would take hundreds of years to grow back. That would make it hard for some of the fish to survive, and probably go extinct. Over fishing could be refering to 'over fishing the area' as in over fishing for what animals are left. (eg taking 1,000 fish from a 50,000 fish area wouldn't matter too much, taking the same amount from a 2,000 fish area would) So, if you get the stuff in brackets, over fishing for the area could eaily happen if it continues like how it is now. And so, in a few years time, it might be that most people who are going fishing on a (big) boat will be over fishing.