The Tasmanian salmonid industry has recently been faced with several significant production issues necessitating increased use of antibiotics and antifoulants. The effects of these chemicals on the local ecology and ecosystem function are currently poorly understood and without evidence to the contrary, it is difficult for the industry to refute the perception that such chemicals have a detrimental effect on the environment.

There is a large body of literature regarding the effects of antibiotics, however the information pertaining to aquaculture is limited. Improvements in husbandry and vaccine development have now all but eliminated the use of antibiotics in aquaculture overseas, consequently there have been few recent aquaculture specific studies, with even fewer studies on ecosystem effects, the available information largely focussing on environmental persistence and antibiotic resistance. However, there is quite a lot of information in the terrestrial livestock and medical areas on the comparative effects of various antibiotics as well as quite a substantial ecotoxicological literature. In contrast there is a substantial local literature on the environmental impacts of antifoulants and heavy metals. There is a need for a targeted review to establish environmental risk factors associated with current antibiotic and antifoulant usage and to develop an appropriate strategy to research and monitor ongoing impacts.

Some data on sediment residue levels for both antibiotics and antifoulants has been collected by the salmon industry in compliance with drug/chemical licensing permit conditions authorities and by the state government in response to concerns regarding antibiotic usage. So far this data has not been collated and has only been subjected to preliminary analysis; a comprehensive evaluation of this data would markedly improve our understanding of current impacts and help to determine what additional information may be required.

Recent research shows general public support for Australia’s fishing industry (Sparks 2017; Voyer et al 2016) that depends on people’s assessments of industry’s commitment to implement best practice and demonstration of being effective environmental stewards (Mazur et al 2014). The FRDC has recognised external pressure for the fishing industry to move beyond compliance with environmental and other regulations and improve its performance in key areas, including animal welfare. As noted above, the FRDC has provided support for a range of research and industry initiatives to achieve positive aquatic animal welfare outcomes. The FRDC also recognises that further improvement to the seafood industry’s aquatic animal welfare practices are required.

Recent FRDC project investments has produced valuable knowledge about how when change is called for it is very important to recognise that multiple factors influence – positively and/or negatively - people’s decisions to take up those new, innovative, and/or different practices (i.e. 2017-133, 2017-046, 2017-221). These factors typically include personal values and belief systems, access to different kinds of resources required to make changes, particular features of the recommended practices, as well as a range of macro-levels factors that while they may be outside of people’s direct control still affect their choices. FRDC Project 2017-133 generated important insights about how and to what extent these kinds of factors have been keeping the seafood industry from making more substantive progress towards building greater stakeholder and community trust (Mazur & Brooks 2018).

Further work of this nature is now needed to shed greater light on aquatic animal welfare in the seafood industry (FRDC 2017-221). In particular the research should be focused on identifying the particular features of ‘best care’ for aquatic animals, the range of factors that may be obstructing industry members’ use of those practices, and examples of recent (extension) initiatives used to encourage better aquatic animal welfare.