People who pioneered reserves, the fishers who gave up part of their fishing grounds in the hope of better times ahead, are beginning to reap benefits from their foresight. Those who wanted to wait and see the evidence first are now feeling they have waited long enough and want to take the plunge themselves. After starting small and accumulating slowly, fully-protected areas are now recognized as a major asset to fishers, fishery managers and conservationists. If you stop fishing an area, none of the animals there will die by getting caught. This means that many individuals will live longer and grow larger.
Bigger animals produce many times more eggs than smaller ones.
Big fish may also spawn more frequently than small. On the Pacific coral reefs of Guam, half kilogram goatfish reproduce four to five times more often than goatfish half this size, and produce 100 times more eggs over a year. Therefore a few very large animals are more valuable as egg producers than many smaller ones. In addition to increases in average body size, reserves often increase population densities. A greater abundance of fish within a reserve will also result in increased egg production relative to fishing grounds.