Federal Antibiotic Permits Suspended Amid Environmental Concerns and Calls for Transparency in Tasmanian Salmon Farming

Federal authorities have suspended an emergency permit for florfenicol, an antibiotic used in Tasmanian salmon farms, following its detection in wild marine species up to 10.6 kilometers from treatment sites. Concurrently, new details have emerged regarding the use of another antibiotic, oxytetracycline, in freshwater salmon hatcheries, prompting calls for greater transparency. These developments occur as the federal government faces criticism for legislative changes that circumvented a departmental recommendation to reassess salmon farming approvals in Macquarie Harbour, an area critical for the endangered Maugean skate.

Florfenicol Permit Suspension and Off-Site Detections

The Australian Pesticides and Veterinary Medicines Authority (APVMA) suspended the emergency permit for florfenicol, which was granted in November 2024. The permit was originally issued to address a Piscirickettsia salmonis bacterial outbreak in Tasmanian salmon farms, an event that led to the deaths of millions of salmon.

The suspension, announced following a review of industry information by a March 2, 2025 deadline, was attributed by the APVMA chief executive to an "unacceptable risk of residue exposure" to non-target species. Specifically, concerns were raised regarding potential impacts on seafood export markets.

Detection Findings

Data from the Institute for Marine and Antarctic Studies (IMAS), collected for Tasmania's Department of Natural Resources and Environment (NRE), revealed "very low levels" of florfenicol in 165 out of 840 samples from wild marine species. These species included lobsters, abalone, sea urchins, whelks, and bryozoans.

The furthest detection occurred at Standaway Bay, approximately 10.6 kilometers from the salmon treatment locations. Florfenicol was found in some parts of lobsters but not in their tails, and was not detected in oysters, mussels, or periwinkles.

Health and Market Implications

While Public Health and the Department of Natural Resources and Environment Tasmania (DNET) stated that the detected trace levels do not pose a risk to human health from seafood consumption, even minimal detections could violate strict international market requirements, potentially affecting Tasmania's seafood export industries. As a precautionary measure, temporary closures of commercial wild fisheries have been implemented around recently treated salmon farms, including two zones near Bruny Island.

Industry and Regulatory Perspectives

Salmon Tasmania CEO John Whittington stated that florfenicol is considered a "global gold-standard" antibiotic, essential for salmon health, and was used "solely to ensure our fish are healthy." He affirmed the industry's commitment to environmental responsibilities and maintained that the antibiotic does not impact waterway environmental health or the safety of wild-caught fish. The industry is reportedly developing new vaccines to reduce medication needs.

Internal documents obtained through right-to-information requests showed that Tasmanian government agencies, including the Health Department and Environment Protection Authority, had previously questioned the scientific rigor of the initial florfenicol application. They expressed concerns about a lack of robust, Tasmania-specific evidence regarding human health impacts or antibiotic resistance.

Dr. Mark Blaskovich, an antibiotic resistance expert from the University of Queensland, noted that the detected concentrations, while low, are within a range "ideal for generating resistance," and warned of potential cross-resistance to antibiotics used by humans.

Political and Community Response

Independent MP Peter George stated that the findings indicate the antibiotic should be banned. He emphasized concerns from the rock lobster and abalone industries regarding potential pollution and trade impacts, and highlighted the global health issue of antibiotic resistance.

State Greens leader Rosalie Woodruff called for the state government to withdraw support for the antibiotic's use and for the immediate destocking of diseased salmon pens, advocating for the prioritization of environmental and local industry interests.

Oxytetracycline Use in Freshwater Hatcheries

Huon Aquaculture utilized the antibiotic oxytetracycline at its Meadowbank freshwater hatchery in Tasmania to treat diseased salmon. This facility is situated approximately 40 kilometers upstream from the Bryn Estyn water treatment plant.

The company stated the antibiotics were deployed as a 'last line of defence' due to an increase in fish mortality caused by an intestinal bacterial infection, which followed a spike in water temperature in mid-January. This infection was noted as distinct from the bacterial disease impacting coastal marine farms.

Transparency Concerns and Regulatory Response

Unlike florfenicol use in coastal marine farms, there are no mandatory public disclosure requirements for antibiotic use in freshwater hatcheries.

Huon Aquaculture, however, made a voluntary disclosure to the Environment Protection Authority (EPA). In response, the EPA implemented antibiotic residue monitoring at Meadowbank Hatchery and announced that these new regulatory requirements, including monitoring, would be applied across all freshwater hatcheries in Tasmania, with results to be published on the EPA website.

Health and Environmental Concerns

Independent Member of the Legislative Council (MLC) Meg Webb criticized the existing lack of transparency surrounding antibiotic use in salmon farms, advocating for mandatory full public disclosure.

The World Health Organization (WHO) classifies oxytetracycline as a 'highly important antimicrobial' and has raised concerns about antimicrobial resistance stemming from misuse and overuse.

The Greens called for the government to mandate real-time disclosures for all antibiotic use in Tasmanian waters. Health Minister Bridget Archer affirmed that antibiotic use in Tasmania's agricultural and aquacultural industries is "heavily regulated" and stated no concerns about public health risks.

Macquarie Harbour Salmon Farming and Maugean Skate Concerns

The Albanese government enacted legislation in March 2025 concerning salmon farming in Tasmania's Macquarie Harbour, following advice that indicated "substantial new information" about its environmental impact. Documents obtained via freedom of information laws revealed that in January 2024, the federal environment department advised then Environment Minister Tanya Plibersek to revoke a 2012 decision that had allowed salmon farming expansion in the harbor without a full environmental impact assessment (EIA).

Department officials indicated that the expansion significantly affected the endangered Maugean skate, an ancient ray-like species exclusive to Macquarie Harbour, and the Tasmanian Wilderness World Heritage Area. The advice highlighted that salmon farming was reducing dissolved oxygen levels, impacting the skate's habitat, behavior, physiology, and population. Revoking the approval would have required the salmon industry to cease operations in Macquarie Harbour pending an EIA.

Government Action and Criticism

The Labor government rejected the department's recommendation and introduced legislation that limited when third parties not directly involved in a development application could request decision reconsideration. Prime Minister Anthony Albanese stated these changes would ensure "appropriate environmental laws" for "sustainable salmon farming."

Environment Minister Murray Watt subsequently rejected the reconsideration request lodged by environmental organizations and formally approved the continuation of salmon farming in Macquarie Harbour in August 2024. Minister Watt decided to retain the Maugean skate's status as endangered, rather than upgrading it to critically endangered, based on advice from the Threatened Species Scientific Committee.

Critics, including Tasmanian Greens senator Peter Whish-Wilson and various conservation groups, stated that the government disregarded departmental advice and scientific evidence, asserting that the Prime Minister undermined environmental law.

A government spokesperson stated that the departmental advice was specific to a legislative framework that was no longer in place, expressing a desire for a sustainable salmon industry that supports workers and protects the environment.

Ongoing Legal and Environmental Efforts

The government's decision is currently subject to a Federal Court challenge by NWTAS for Clean Oceans, an organization opposed to salmon farms.

The Maugean skate has been listed as endangered since 2004, with concerns heightened in 2024 when a government scientific committee reported "extremely low" numbers. A later IMAS report suggested the skate population might have recovered to 2014 levels but remained endangered, emphasizing the need for continued monitoring.

Since 2021, the federal government has allocated $37.5 million towards improving water conditions, including oxygen levels, in Macquarie Harbour. This funding includes $10 million for a captive breeding program for the Maugean skate.