Earlier this year I wrote about lifeboat islands in New Zealand and the insights to be gained from exploring biodiversity.
This week a report has been published that gives us a detailed picture of performance management … from the perspective of coral reef ecology. The report is titled Critical thresholds and tangible targets for ecosystem-based management of coral reef fisheries and has been written by Tim McClanahan, Nicholas Graham, Aaron MacNeil, Nyawira Muthiga, Joshua Cinner, Henrich Bruggemann and Shaun Wilson. It was published in this week’s online edition of the Proceedings of the National Academy of Sciences of the USA.
The report is available as an open access document. The abstract is:
Sustainably managing ecosystems is challenging, especially for complex systems such as coral reefs. This study develops critical reference points for sustainable management by using a large empirical dataset on the coral reefs of the western Indian Ocean to investigate associations between levels of target fish biomass (as an indicator of fishing intensity) and eight metrics of ecosystem state. These eight ecological metrics each exhibited specific thresholds along a continuum of fishable biomass ranging from heavily fished sites to old fisheries closures. Three thresholds lay above and five below a hypothesized window of fishable biomass expected to produce a maximum multispecies sustainable yield (BMMSY). Evaluating three management systems in nine countries, we found that unregulated fisheries often operate below the BMMSY, whereas fisheries closures and, less frequently, gear-restricted fisheries were within or above this window. These findings provide tangible management targets for multispecies coral reef fisheries and highlight key tradeoffs required to achieve different fisheries and conservation goals.
My take on this fascinating report? I think that the concepts of:
- critical reference points for sustainable management
- metrics of ecosystem state
- tangible management targets
- key tradeoffs
… are of fundamental interest to all those interested in developing and sustaining a critical mass of performance potential and consistent, sustainable high level of performance.