University of Tasmania
Final Thesis - PETHIYAGODA - expubmat.pdf (3.11 MB)

Relative values of the coastal and marine environment : ecosystem service valuation in multi-use governance contexts

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posted on 2024-03-27, 05:50 authored by Niyomi PethiyagodaNiyomi Pethiyagoda

Globally, the finfish aquaculture industry has experienced a decline in levels of social acceptability as the industry has been linked to direct impacts on the coastal and marine environment. However, the magnitude and intensity of these impacts are highly contested and controversial. To achieve socially acceptable aquaculture expansion, the risks of negative impact on coastal and marine ecosystem services must be mitigated or minimised. A range of ‘greener’ alternative finfish production technologies exists, including multi-species aquaculture, offshore and onshore aquaculture, although these are not yet commercially viable in all regions. Public investment in research and development will likely be required to make viable the transition to those new finfish aquaculture technologies at full commercial scale. Therefore, evidence of public and stakeholder values for and the social acceptability of emerging finfish aquaculture production technologies can inform the processes of public and private (industry) policy development and decision-making.
The overall aim of the research was to provide an analysis of public and stakeholder preferences for the adoption of alternative forms of finfish aquaculture production technologies. A further aim was to investigate public preference for policies to support the transition to alternative production systems. A systematic qualitative method was used to inform and provide a comparison to a quantitative analysis of stated preference values held by local people for affected coastal and marine ecosystem services and flows. It uses the state of Tasmania, Australia, as a case study.
A stakeholder and a public survey were utilised in a mixed-method approach to address this study’s aims. The stakeholder survey allowed preliminary analysis of the research questions using Q methodology to determine relative preferences for a range of coastal and marine ecosystem services potentially impacted by marine finfish aquaculture in Tasmania. Q methodology was applied as a valid, standalone method to understand stakeholder preferences. This methodology also provided a form of systematic qualitative assessment of attribute salience for the purposes of the pre-design of the public survey, which included a discrete choice experiment that allowed the estimation of monetary values for affected coastal and marine ecosystem services. This combination of methods demonstrated the utility of applying Q methodology as a systematic approach for identifying locally held salient values to inform the design of subsequent stated preference research. The public survey also included attitudinal questions designed to describe levels of public preferences for a range of public policies for planning and management of the expansion of the finfish aquaculture sector in Tasmania.
The research identified that most stakeholders followed a ‘utilitarian ecological’ perspective. For this group, the ecological condition of surrounding marine reefs and systems that support productivity and the economic benefits flowing directly and indirectly from finfish aquaculture were equally important. Impacts on recreational users, visual/noise amenity or aesthetic values were less important. Small subsets of respondents’ perspectives focused on ‘ecological primacy’ or ‘recreational amenity’.
The stakeholder research identified seabed health, water quality and the flow of benefits to regional communities through employment directly and allied economic sectors as important ecosystem services. Except for the positive economic benefits, there was a high level of consensus across stakeholders that a range of impacts from aquaculture on coastal and marine ecosystem services was perceived to be detrimental and occurring in Tasmania.
Through analysis of the DCE survey, monetary values were estimated for the coastal and marine ecosystem services affected by finfish aquaculture expansion identified as the most important in the Q methodology study. The coastal and marine ecosystem services valued in the DCE were ‘water clarity’, ‘seabed and other nearshore marine habitats’ and ‘employment opportunities’. The DCE results showed a significant positive willingness to pay (WTP) for improvements to water clarity and employment opportunities. The seabed and other nearshore habitat attributes were found to be statistically insignificant, which contrasts with the results of the Q methodology, which indicated that it was one of the more important coastal and marine ecosystem services impacted by finfish aquaculture in Tasmania for stakeholders. The results suggest it is possible that Tasmanians may feel that current legal requirements of no impact beyond 35 metres from leases represent a level of impact they can tolerate or may indicate a divergence in attitudes between stakeholders and the public.
Finally, public preferences for alternative finfish technologies and types of policies to govern industry expansion and transition were determined through analysis of direct preference questions in the public survey instrument. Based on its effects on coastal and marine ecosystem services, the preferred production technology was MSA. MSA was also the production technology given the highest level of priority for public investment in research and development (R&D), although participants preferred diversified R&D investment rather than investment in one technology alone. The level of prior knowledge of the alternative production technologies did not appear to influence preference, as MSA was the form of technology public respondents were the least informed about. Respondents preferred a stronger role for government through direct regulation, public sector–funded economic incentives, and ‘green’ taxes and levies to adopt new technologies—in contrast to industry-led self-regulation.
The results from the multiple methodologies deployed provide targeted information to support public agency decision-making in Tasmania concerning its role in planned finfish aquaculture expansion. The study has addressed knowledge gaps limiting this decision-making and planning, specifically perceived trade-offs between economic and environmental impacts of finfish aquaculture, public policy preferences and technology preferences. It makes a methodological contribution by combining multiple methods to reduce the likelihood of bias in the measurement of preferences using DCEs and increase a holistic understanding of stakeholder and public preferences. It does this by identifying the presence of subjective perspectives across stakeholders and the influence of prior knowledge and other psycho-social factors on preference formation.



  • PhD Thesis


xviii, 344 pages


Tasmanian School of Business and Economics

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