Effects of Marine Reserve Protection on Adjacent Non-protected Populations in New Zealand

Marine reserves (MRs) have been established in many parts of the globe for a variety of reasons and there is an increasing body of evidence that indicates they provide a wide range of benefits that can extend beyond their boundaries. In the present study, the biological effects of protection provided by MRs in New Zealand were evaluated, particularly focusing on the potential impacts of reserves on non-protected areas in terms of export of biomass. First, the biological response of two exploited species to MR protection in New Zealand was quantified by comparing meta-analysis results based on response ratio (RR) analysis and Hedges’ g statistics. Then, effect of MR size and age on those biological responses was determined. Most MRs supported a greater density of larger individuals than unprotected areas. Results indicated that the benefits provided by MRs scale with reserve size. Also, MR age explained a significant amount of the variation in the density and length of both species. Comparison of the performance of RRs with Hedges’ g revealed that RR analysis is an appropriate alternative to Hedges’ g statistic for meta-analyses of MR effectiveness because of its ease of use and interpretation. Then, a 14-year time series of fish density data was analyzed to determine early changes in a multi-species fish assemblage inside the Taputeranga Marine Reserve (TMR) compared to adjacent fishing grounds using a Before and After Control-Impact Paired Series (BACIPS) design. This analysis was performed in order to detect changes in fish density due to protection. Commercial, recreational and traditional fisheries are important in this region and the biomasses of several exploited species have been substantially depleted as a result of fishing. The exclusion of fishing from the area should enable at least some species to recover inside the reserve, as has happened in other reserves in New Zealand. The faster growing, more productive species, and those that have been heavily exp