SCIENTISTS researching the movement of mulloway in south-west Victoria have identified the fish equivalent of a marathon swimming champion.
Arthur Rylah Institute Fish Ecology Scientist Jason Lieschke said: “One of the mulloway electronically tagged as part of the survey clocked up an oceanic swim of around 800 kilometres, travelling from the Glenelg River estuary in Victoria, to the Murray mouth in South Australia and back again.”
“We’ve been monitoring the movements of the mulloway over the past two and a half years using acoustic tags that were surgically implanted into 30 fish in the Glenelg River and this long distance swim has been the most surprising result so far,” Lieschke said.
“Three out of the 30 tagged fish made the trip to the Murray mouth in South Australia, approximately 400 kilometres away, but so far just one made this extraordinary round trip.”
“This work has significantly increased our knowledge of how the Mulloway behaves and the tags are expected to keep going for another six months.”
The research also revealed that individual fish can swim up to 50 kms up and down the Glenelg River estuary over a four day period; one tagged fish left the Glenelg River estuary and entered the Southern Ocean. The mouth of estuary was then blocked with sand. The fish then returned to the estuary three weeks later when the mouth re-opened.
The mulloway also have external tags to identify them as part of the research program. The tag has a phone number for anglers to call to pass on information such as the tag number, date, location and length of fish before release. If an angler keeps a tagged fish, it would assist research if they recorded the date, location and fish length and send the acoustic tag to the address supplied.
