Within three years, commercially important fish stocks tripled in the protected zones and doubled in the fishable areas. New jobs also opened to support growing tourism. Roberts also points up the benefits of closing fishing for groundfish and scallops at Georges Bank in the Gulf of Maine in 1995. This is not a fully protected area - other fish are still caught here. But Roberts says it gives insights into how a large fully protected reserve would work.
Fishers reap rich harvests as currents carry young scallops out of the protected zone.
Theory suggests that networks of relatively small protected reserves interspersed with fishable areas give stability and resilience. The reserve areas then need to be spaced to take advantage of their interaction. They may exchange larvae, for example. The theory has to be tested. It also raises political issues.