The Inland Fisheries Service (IFS) has completed a targeted operation to eradicate invasive redfin perch from two farm dams in the Huon Valley, following the first detection of the species in the region.

The issue was first identified on 12 March 2023, when an angler caught a redfin perch in Mountain River — the first confirmed record in the Huon Valley catchment.

Despite extensive surveys of rivers, creeks and farm dams between April 2023 and early 2024, only one additional fish was located. Public awareness campaigns were then launched to encourage anglers and residents to report any further sightings.

In May 2025, new information led IFS to investigate several farm dams, confirming two established redfin perch populations. Both dams periodically overflow into Mountain River, making them the most likely source of the earlier detections.

In April 2026, IFS carried out a coordinated eradication program. Water levels in both dams were reduced before applying rotenone, a targeted fish management treatment. Within 30 minutes, redfin perch began surfacing, with individuals ranging from 100 mm to 420 mm in length. Initial results indicate the treatment was successful, with follow-up surveys scheduled in 12 months to confirm eradication.

While the response extended over several years, the outcome highlights the importance of community vigilance and sustained investigation. Early detection, public reporting, and targeted management play a critical role in preventing invasive species from establishing and spreading.

Although the dams are likely to have overflowed into Mountain River over recent years, the river’s fast-flowing nature, combined with repeated survey efforts, suggests redfin perch have not successfully established a significant population in the system.

Redfin perch are a highly invasive species that can significantly impact native fish and recreational fisheries. The successful removal of these populations greatly reduces the risk of further spread within the Huon catchment.

IFS encourages anglers and members of the public to continue reporting any unusual pest fish captures. Take a photo of the fish, or carcass if found and if possible, retain it.  Please take note of the location where any suspect fish were seen (or caught), as well as the date, and contact the IFS promptly on 1300 INFISH or infish@ifs.tas.gov.au.