Antibiotic name and dosing period
Florfenicol 100% Active. Two 10-day treatments under 2 Veterinary Authorities, with the first treatment starting on 15 February 2026 and the final treatment finishing on 3 March 2026.
Summary of sampling rounds undertaken
The original monitoring schedule required that water, seabed sediment and wild fish samples were collected immediately after treatment (day 1 post-treatment, day 7 post-treatment, day 21 post-treatment).
An Addendum to the monitoring schedule was issued due to the receipt of an additional Veterinary Authority for this lease. The Addendum required that these samples be collected weekly until all treatments on the lease had finished and 2 consecutive results below the limit of reporting were received and the Director had authorised that sampling be stopped.
Samples were collected at sites both inside the lease (pen bays and centroids) and outside the lease, including compliance sites, transect sites, and reference sites.
In total, 251 individual wild fish samples were caught and analysed across 3 zones (within 1 km, between 1-3 km and greater than 3 km) from the lease boundaries. The 251 wild fish samples included 12 benthic and pelagic species, being Australian salmon, barber perch, barracouta, blue mackerel, blue-throated wrasse, gurnard, jack mackerel, jackass morwong, pike, red cod, rock cod, sand flathead, senator wrasse, and snapper.
In total, 51 sediment samples and 204 water samples were collected and analysed at multiple distances from the pen bays and including a reference site approximately 6.3 km from the lease boundary.
Assessment of compliance against the schedule issued by the EPA
The report is compliant with the requirements of the Therapeutant Residue Monitoring Schedule – Marine Farming Lease No. 94 (The Sheppards) – February 2026, Addendum - Therapeutant Residue Monitoring Schedule – MF94 – The Sheppards - 27 February 2026, section 28(2) of the Environmental Standards for Tasmanian Marine Finfish Farming 2023, and any minor variations approved by the EPA Director.
Summary of findings in report
The water and sediment results outlined in this report align with the EPA's Preliminary analysis of environmental samples for florfenicol in southern Tasmania with negligible detections of florfenicol in seabed sediments and rapid depletion of the low level detections in the water column in the days after treatment.
EPA's assessment of potential environmental impacts
The EPA has completed a significant body of work to establish a guideline value for ecotoxicity of florfenicol in aquatic environments and has reviewed all of the water and sediment data collected under florfenicol residue monitoring schedules against this guideline value. The EPA has found that florfenicol residues present low risks to aquatic ecosystems. For further information, including a detailed scientific report, please see Environmental risk assessment of florfenicol use in marine salmonid aquaculture in SE Tasmania 2025 – 2026.
Statement from the Director of Public Health
Public Health Services notes the reports of florfenicol residue detected in wild finfish samples (mostly in blue mackerel) at this lease.
Residue of florfenicol and metabolites was detected in 6 of 24 wild finfish samples caught within 1 km of the treated lease during and shortly after 2 overlapping periods of treatment. Residue of florfenicol and metabolites was also detected in 8 of 71 wild finfish samples caught more than 1 km from the treated lease during the same time period. These 8 more distant samples were all among the 47 samples collected from reference sites more than 3 km from the treated lease. Eating typical amounts of these wild finfish does not pose a risk to health.
Residue of florfenicol and metabolites was detected in 2 of 132 wild finfish samples caught more than a week after the end of treatments. The 2 samples with very low concentration detections were among the 108 samples collected more than 1 km from the lease.
Public Health Services has reviewed all results to date and maintains its precautionary advice, which is available on the Department of Health website.
Link to final report:
Final Report - Therapeutant Residue Monitoring Program - MFL 94 The Sheppards (PDF 3Mb)
Given treatment occurred concurrently at MF94 The Sheppards and MF142 Roberts Point, with some overlapping sampling sites, it is recommended that this report should be considered in conjunction with the Roberts Point report.