Getting on board with biosecurity: Evaluating the effectiveness of marine invasive alien species biosecurity policy for England and Wales

Marine Invasive Alien Species (IAS) can have devastating impacts on the environment, infrastructure and human well-being. Prevention measures, such as biosecurity, are essential to reducing the introduction and spread of IAS and are central to international and national IAS policy. Understanding the motivations of stakeholders can help determine the effectiveness of existing policy instruments on behaviour. 14 semi-structured interviews were conducted between two case study stakeholder groups in England and Wales (marine shellfish aquaculture industry and the recreational boating sector) in early 2018. Biosecurity practices were deeply embedded in the heavily regulated practices to control shellfish disease within the shellfish industry. Motivations to undertake biosecurity were driven by economic incentives, and penalties for non-compliance with legislation controlling disease. In contrast, there are little regulatory policy instruments to drive IAS biosecurity within the recreational boating sector, which instead relies heavily on voluntary instruments to motivate stakeholders and encourage behavioural changes. Behavioural changes, however, were restricted by lack of infrastructure and enforcement. Our findings suggest it is important to use a combination of approaches to achieve behavioural changes but recognising where regulations and penalties cannot be enforced, voluntary instruments are likely to be most effective. Existing social norms and investment into infrastructure should ‘nudge’ individuals into socially desirable behaviours, especially in the recreational boating sector. For policy makers and regulators, this research reveals the importance of tailoring biosecurity strategies to different stakeholder groups as motivations and collective experience differ.