NIWA's Derrick Parkinson tagging a snapper. Photo / Supplied
NIWA's Derrick Parkinson tagging a snapper. Photo / Supplied
A South Taranaki fisherman has pulled up a fish in the same week, in almost the same location, 20 years after it was tagged by researchers.
When Chilton Atherton, who goes by the name Mr Chilt, was filleting some snapper he caught off the Pātea coast on February 27, he was surprised when a tiny metallic tag popped out of the fish's head.
"I thought it was the booster shot," he joked, referring to the Covid-19 vaccination.
He said he could see the tag was electronic so he asked a friend who runs a South Taranaki fishing charter about it.
That friend told him to contact the National Institute of Water and Atmospheric Research (Niwa) to find out more.
Niwa said the tag, known as a passive integrated transponder (PIT), had been put in the fish on February 21, 2002, by principal technician Derrick Parkinson, who still worked for the research institute.
That meant the fish had been caught almost 20 years to the day after its tagging.
Not only that, Niwa's fisheries programme leader Dr Darren Parsons said Mr Chilt had caught the snapper in almost the exact same location it was tagged.
Between the tagging and being caught by Mr Chilt the snapper went from being 49cm long and about 2.35kg to 65cm long and 5.17kg.
It more than doubled its weight in 20 years as well as growing 16cm longer.
Niwa said it no longer tagged snapper with PITs and the 2002 programme was the last time it was done.
Mr Chilt's snapper was also the only PIT snapper tag to have been reported since 2003, Niwa said.
Parsons said most snapper don't move over large areas.
"This doesn't mean this fish has stayed in that spot without moving for 20 years, although that is possible.
"We know many snapper undertake a seasonal migration, bringing them inshore for spawning over the warmer months. The capture of this fish could therefore be a reflection that it was following the same seasonal movement patterns it was 20 years ago."
Niwa's 2002 tagging programme was so that it could estimate the biomass of snapper off the west coast of the North Island, with the data then given to the Ministry of Primary Industries (MPI) for managing fishery stock targets.
Mr Chilt, who has been fishing for 45 years, credited his catch to his lure.
"I got to my fishing possie, dropped down the old 'ham on the bone' - that's the name of my homemade fishing lure - and began catching big snapper straight away. I released most of them back but took some home with me."
