The condition of Australiaʹs marine environment is good but in decline—An integrated evidence-based national assessment by expert elicitation

The condition and trend of 196 marine environment components were assessed for Australiaʹs national 2011 State of the Environment Report using professional judgements derived by expert elicitation. The judgements from the diverse group of field-experienced scientists and practitioners were assembled within a single framework common to all components to provide an integrated system-level assessment. Components assessed included the natural environmental assets and values in biodiversity, ecosystem health, and the pressures. A high level of agreement was achieved amongst the disciplines and experts on the decision structure and the scores or grades, even though many components are data-poor at the national scale. The assessment confirmed the clear association between human development history and extant condition of the biodiversity and ecosystem health. Overall, the marine environment was considered to be in good condition relative to conditions prior to European colonisation of the Australian mainland. However, more components of the biodiversity were considered to be deteriorating than improving, inferring that the overall quality of ecosystems is in decline. Combined present-day pressures were considered to be greatest in the temperate and the coastal waters (<200 m depth) adjacent to more developed areas of the coast in the South-east region. Here, condition of biodiversity and ecosystem health was considered to be poor, and in some places very poor. Condition in the North region, where there is only limited human development, was considered to be good. The process identified environmental components considered to be in the ‘best of the best’ and ‘worst of the worst’ condition, providing focus for subsequent prioritisation in national environment policies. Gaps identified include a lack of national-scale data on the condition and trend in almost all biodiversity components other than fished species, for which most knowledge is skewed towards resource use. Also, there is a lack of monitoring of the links between national pressures, such as port development, and regional biodiversity condition in response to policy settings and management activity. The assessment process deployed here provides a model for repeatable integrated system-level assessment and reporting at the national and regional scales in data-poor marine situations.