Being a commercial fisherman for most of my life I can definitely say that everything in the ocean runs in cycles. Some years the traps would come up with so many parrot fish we would just take some and let the rest go. Other years it was triggerfish. Still other years everywhere you went, even around the shoreline, all you saw were Small puffers. Every time we went through a cycle, the biologist were up in arms telling us that we were over fishing the stocks. After a year or two u could barely catch a particular species and they would say that we had fished them out. 4 or 5 years later we would go through the same cycle and they would say that due to new restrictions that they had succeeded in rebuilding the stocks even though nothing had changed with our fishing practices. I've seen this happen many times over so I know what you experienced happens worldwide.