MATT Bell’s name has been bandied around the country recently after his 102kg tuna catch off Port MacDonnell.
It was not the biggest tuna caught that weekend and is not a world record, but it has become a famous catch for other reasons.
The Southern Bluefin Tuna is one of the oldest fish to have been tagged and the tag being returned to the CSIRO.
Having never caught such a prized fish previously, Bell, fishing with his friend Dennis Heinicke, decided to keep his catch, but upon pulling the fish aboard and cleaning it up a bit he discovered a tag had been inserted.
Bell then did the right thing and returned the tag to the CSIRO, which was when he discovered the fish was close to 24 years-of-age, having been tagged and released back in 1993 at around two years-of-age.
“Bluey”, as the fish was affectionately dubbed by the CSIRO, was tagged along with 11,000 tuna in the Great Australian Bight in a joint program by the organisation and the Commission for the Conservation of Southern Bluefin Tuna.
The tuna was then caught some 800 kilometres east from that original spot off Port MacDonnell on April 11, with the information gained as a result of the tag being returned proving invaluable to the CSIRO, tracking the tuna’s travels and habits over the two decades.
And it is fair to say as a result Bell was quite proud of his catch.
“I was very excited,” he said.
“The CSIRO said only one or two fish of that age had ever been recaptured so it’s a significant capture I reckon for a recreational angler.
“I’ve only been fishing for tuna and helping tag them for a few years so to catch a fish that old is pretty amazing.”
Bell said while he was initially a bit disappointed to have discovered the tag after the fish was killed, the research value has helped ease that disappointment.
He said the CSIRO was excited to have the tags from his prize catch returned to help with their research.
“The CSIRO were super excited,” he said.
“To have a fish caught that age is rare – there are plenty of professional fishermen who might catch them and may not worry about the tags.
“It is awesome to help the CSIRO with their research.”
And to assist even further, Bell tagged another two big fish that same day.
“This was my first big tuna and I thought I would like to take one because they are beautiful eating,” he said.
“We were a bit disappointed when we noticed the tags but later on we tagged two around the same size ourselves so we felt a bit better for doing that.
“Those two tuna were the biggest game fish – outside of sharks – that have been tagged and released in South Australia, so they are pretty significant fish too.
“One was estimated at 75kg and the other at 85kg.
“The CSIRO was pretty excited about that because there are very few caught for the amount of anglers out there.”
Given the importance of “Bluey”, Bell said it is not just his best catch, but his best experience overall.
“The CSIRO will do a full report when they get the samples so it will be interesting to see what comes through,” he said.
“In the whole scheme of things there are thousands of fish taken each year but not that many tagged.
“I’ve probably tagged close to a hundred in the last three or four years.
“I think recreational anglers should do a lot more tagging to help out.”
In the time since “Bluey” was tagged back in 1993 its travels spanned a vast area, including large parts of the Southern Ocean heading out from the Great Australian Bight and up to the Indian Ocean south of Indonesia where the tuna spawn.
It grew to its 102kg weight while going from 60cm to 191cm in total length.
Samples collected from the fish by Bell will also aid the CSIRO in its research.
By looking at the fish’s otoliths (deposits in the ear) its age can be verified, by looking at its ovaries the sex and reproductive history can be determined and by analysing the chemical composition of the muscles, its diet can be better understood.
For anglers wanting more information about returning tags go the CSIRO blog at http:// csironewsblog.com/2015/04/26/ reunited-after-twenty-yearstagged-tuna-tell-us-tales-of-the-sea/