Informing ecosystem-based management of the range extending long-spined sea urchin using a structured decision making process

Lucy M. Robinson (1) , Martin P. Marzloff (2), Sarah Jennings (3,4), Stewart Frusher (2,4), Sam Nicol (5), Gretta Pecl (2,4), Ingrid Van-Putten (4,6), Alistair Hobday (4,6), Marcus Haward (2,4), Sean Tracey (2) and Klaas Hartmann (2)

1 Commission for the Conservation of Antarctic Marine Living Resources, Hobart, Australia

2 Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia

3Tasmanian School of Business and Economics, University of Tasmania, Hobart, Australia

4Centre for Marine Socioecology, University of Tasmania, Australia

5CSIRO Land and Water, Dutton Park, Australia

6CSIRO Oceans and Atmosphere, Hobart, Australia.

The poleward movement of species is one of the signatures of climate change and is resulting in changes in ecosystems that in turn are posing significant challenges for managers of marine resources and biodiversity. This is particularly the case where there are multiple stakeholders with different and often conflicting views on appropriate management action. A structured decision making process can assist managers in identifying some disparity between objective and subjective elements that may underpin stakeholder disagreement. In southeastern Australia the recent arrival and establishment of the barren forming urchin (Centrostephanus rodgersii – which converts algae covered reef to barren reef) has resulted in impacts to valuable commercial and recreational reef fisheries and coastal reef biodiversity resulting in a range of ecological, social and economic consequences. We applied a Structured Decision Making process to assist managers and stakeholders with identifying cost-effective management interventions in barren and non-barren reef states that will best address the interests of the stakeholder groups. A workshop and two successive surveys were used to elicit information on stakeholder’s objectives and preferences for management interventions. The consequences of alternative management scenarios (in terms of potential benefits) were simulated for 10 years using a model that captures the dynamics of southeast Australian reef communities. Information on these benefits in combination with the estimated cost and feasibility of management interventions were then used to construct a cost-effectiveness ranking. The sensitivity of the management intervention ranking to the inclusion or exclusion of various components in the cost-effectiveness calculation was also explored.