The pace of environmental change can doom or save coral reefs

To be fair overfishing is not just about locals; there are mother ships also, floating factories that visit areas with the support of a satellite fleet, fill the ship hull and then return to their country. Every country does it. China does it, and Spain also. There are treatises between two countries that regulate number of captures and periods allowed, so if both countries benefit there and the fisheries are scientifically managed shouldn't be a big problem.

The problem is that sometimes people fish under fake flags and sometimes there are also pirate fishing, turning off radio beacons and entering in protected areas at night. The sum of all factors, (legal locals, legal foreign and illegals) results in a overfishing problem that is always complicated to correct and if possible it takes ages to recover because the ecosystems just shrug and move on.

For example NW Atlantic cod collapsed in 1990 in US and Canada. Thirty years passed and the ecosystem achieved to reach a new stable situation, one without cods. It probably will never recover.

I think it's more:

Give a man a fish and he'll have food for a day, Teach a man to fish and he'll have food for the rest of his life. give a man a dollar per fish and he'll deplete his local ecosystem.