Potential Contributions of Marine Reserves to Sustainable Fisheries: Recent Modeling Results

Marine reserves are being recommended worldwide as a means of protecting bio-diversity and increasing fishery sustainability. This has created a need for policy makers to understand how marine reserves can contribute to sustainable fisheries, relative to other approaches. The contribution of marine reserves to the problem of sustainable fisheries depends on whether they can control catch better than conventional fishery management. Models with sedentary adults indicate the effect of marine reserves on fishing is approximately equivalent to the effect of conventional management. This implies that implementation of marine reserves typically will increase yields only in fisheries with excessive effort. Reserves can produce greater catches than conventional management when spatial heterogeneity and movement dominate. However, that will require knowing movement patterns. Reserves are more robust to the uncertainty in current estimates of abundance and the effects of fishing regulations, but they depend to the same degree on the poorly known level of lifetime reproduction required for sustainability, and on highly uncertain larval dispersal distances. Marine reserves may also provide some unique benefits such as maintenance of quasi-natural marine ecosystems, reduction of by-catch, reduction of habitat damage, and a potential for managing multi-species fisheries in data poor situations.