Wanda was first detected at the Koondrook Fishway on Gunbower Creek in October 2023, before being recorded more than a year later at the Kerang Fishway on the Loddon River in December 2024.
Experts believe the fish travelled from Gunbower Creek into the Murray River, down the Little Murray River and into the Loddon River before reaching Kerang Weir.
North Central Catchment Management Authority Native Fish Recovery Plan project manager Peter Rose, said the journey was the longest likely route Wanda could have taken.
“It’s a remarkable movement for a fish species that rarely travels more than five kilometres from home,” Dr Rose said.
The journey also highlights the importance of fishways, which allow fish to bypass barriers such as weirs and move freely up and downstream.
Wanda passed through at least three fishways, each fitted with tag readers that help researchers track fish movement.
Through partnerships with Goulburn Murray Water, the Arthur Rylah Institute, First Nations groups and other stakeholders, more than 1000km of waterways have been reopened to native fish species, including freshwater catfish, Murray cod and golden perch.
Arthur Rylah Institute scientist Wayne Koster said Wanda’s journey showed how improved river connectivity could support native fish recovery.
“Large movements like this are unusual for freshwater catfish, but they demonstrate the value of fishways and environmental flows,” he said.
The Native Fish Recovery Plan is supported by state and national government programs and water authorities working together to protect Victoria’s native fish populations.