Horizontally integrated aquaculture development: Exploring consensus on constraints and opportunities with a stakeholder Delphi

Horizontal integration represents a technically viable opportunity for aquaculture producers to reduce environmental impacts whilst apparently enhancing production efficiency and gaining from economies of integration. Despite significant research, pilot-scale developments and recommendations advocating adoption by producers, uptake has been limited. Consequently, research was undertaken, invoking the iterative Delphi methodology, to explore consensus amongst a multidisciplinary stakeholder panel concerning the nature and significance of constraints and opportunities associated with horizontal integration. Round 1 participants (n = 24) submitted 84 and 94 statements identifying constraints and opportunities, respectively, within physical, environmental, managerial, institutional, economic and social subcategories; aggregating similar statements produced 29 distinct constraints and 27 opportunities for subsequent evaluation. Friedman's randomised block analysis indicated similar rank patterns (P < 0.001, two-tailed) in the distribution of weights assigned to opportunities and constraints by panel members after round 3. Kendall's coefficient of concordance (W) indicated that agreement on constraints was 'strong' and confidence in rank patterns 'high'; agreement was 'very strong' and confidence 'high' to 'unusually high' concerning opportunities. Agreement within subcategories ranged from 'unusually high' for physical and environmental constraints and opportunities to 'moderate' for institutional and social constraints. Economic, physical and managerial constraints were ranked highest, as compared with environmental and physical opportunities. These findings confirm that constraints and opportunities associated with horizontal integration are multifaceted and that a multidisciplinary, systems-based approach to aquaculture development is critical. Furthermore, the stakeholder Delphi constitutes a promising approach to facilitating constructive dialogue and consensus-building amongst diverse, antagonistic and hierarchical stakeholder groups frequently associated with aquaculture development.