Effective marine offsets for the Great Barrier Reef World Heritage Area Melissa Bos a,b, *, Robert L. Pressey a , Natalie Stoeckl b a Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia b Discipline of Economics, School of Business and the Cairns Institute, James Cook University, Townsville, Queensland 4811, Australia e n v i r o n m e n t a l s c i e n c e & p o l i c y 4 2 ( 2 0 1 4 ) 1 – 1 5 a r t i c l e i n f o Keywords: Great Barrier Reef World Heritage Area Biodiversity Offsets Mitigation Compensation a b s t r a c t Biodiversity offsets are a prevalent mechanism to compensate for development impacts to natural resources, but the appropriateness and efficacy of offsets remain the subjects of research and debate. Effective offsets for impacts to marine resources present even more challenges than those for terrestrial impacts. The Great Barrier Reef World Heritage Area is globally valuable for both biodiversity and heritage, but coastal development is under- mining these values, and more effective offsets are needed to compensate for the damage. To improve the effectiveness of marine offsets for the Great Barrier Reef, we recommend that: (1) proponents be required to follow and document their adherence to the mitigation hierarchy, which considers offsets only as a last resort after avoidance and mitigation, (2) proponents and regulators consider the risk of offsetability prior to offset design, (3) the Australian government require offsets to achieve additional, measurable net benefits, relative to the counterfactual baseline, for all affected values, (4) specialist third parties (not government or proponents) design and implement marine offsets, (5) offsets are direct and specific to the affected values, with very minimal investment into research, (6) offsets are consolidated into strategic implementation sites, with long-term legal protection, that are consistent with the zoning of the Great Barrier Reef Marine Park and adjacent coastal land uses, (7) the time between impact and net benefit should be minimized, and net benefits should be maintained in perpetuity, (8) proponents pay the full cost of offset implementation, monitoring and evaluation, and cost is agreed upon before the develop- ment is approved, and (9) monitoring of the efficacy of offsets is separate to but coordinated with regional monitoring programs for ecosystem health, and monitoring data are made publically available. Within this context, and with careful and rigorous methods as de- scribed herein, offsets can contribute to maintaining the Outstanding Universal Value of the multiple-use World Heritage Area. # 2014 Elsevier Ltd. All rights reserved. * Corresponding author at: Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia. Tel.: +61 7 4781 4000. E-mail address: Melissa.Bos@my.jcu.edu.au (M. Bos). Available online at www.sciencedirect.com ScienceDirect journal homepage: www.elsevier.com/locate/envsci http://dx.doi.org/10.1016/j.envsci.2014.05.002 1462-9011/# 2014 Elsevier Ltd. All rights reserved.