Multivariate life-history indices of exploited coral reef fish populations used to measure the performance of no-take zones in a marine protected area

We investigate the use of multivariate life-history indices to assess the performance of no-take zones with respect to ameliorating the impacts of harvest on exploited coral reef fish populations in the Great Barrier Reef Marine Park. A range of life-history parameters were estimated for the two major target species of the Great Barrier Reef (GBR) line fishery, common coral trout (Plectropomus leopardus) and red throat emperor (Lethrinus miniatus), collected from five adjacent reefs (three of which were closed to all forms of fishing) in each of three geographically dispersed regions between 1995 and 1998. Life-history parameters were used to compare the status of populations on open and closed reefs over regions and years. Principal components (PC) analyses were used to effectively reduce the number of parameters to four significant PCs for each species, accounting for 84% and 94% of the total variation in the data for common coral trout and red throat emperor, respectively. We were able to clearly identify those populations that were sampled from reefs open or closed to fishing based on the multivariate descriptors of life-history parameters. The concurrent use of several life-history indices maximised our potential to differentiate changes related to no-take zones from background variation. © 2005 NRC.