The Maugean skate, a prehistoric ray species, is still facing a 'catastrophic' risk due to salmon farming, according to Commonwealth advice. This advice highlights the impact of salmon farming on the skate's habitat and survival, despite efforts to mitigate these effects. The skate's only known habitat, Macquarie Harbour in Tasmania, has seen a drastic decline in its population, with estimates fluctuating over time. The Commonwealth's Threatened Species Scientific Committee has consistently pointed to salmon farming as the primary driver of habitat stress for the skate. The report emphasizes that the skate's survival is threatened by the prolonged reduction in dissolved oxygen levels, which is directly linked to the organic carbon released by salmon farms. This carbon is more biologically available and retained deeper in the water, creating a major problem for the skate. The committee's advice suggests that the skate is now at or possibly beyond its tolerance limits for environmental change. Mitigation measures, such as reducing fish feed levels and implementing oxygen mitigation plans, have been implemented, but the extent of their effectiveness is still being determined. The Commonwealth is also funding a reoxygenation program, which involves pumping dissolved oxygen bubbles into the harbour. However, the committee believes that the most immediate and effective solution is to reduce the amount of salmon being farmed in the next 12 months. This recommendation has been consistent since 2023, and the Environment Minister Murray Watt has stated that he will follow the science. Despite this, the industry 'champion' Anne Urquhart has expressed her support for the minister's decision, emphasizing the need to balance environmental protection with job preservation. The controversy lies in the balance between scientific advice and industry interests, and the question of whether the reduced fish biomass advice will be followed remains to be seen. The skate's future hangs in the balance, and the outcome of these decisions will have significant implications for the species' survival.
