While fishermen flock to the coast over the holiday period, reports of skinny, pale, and what experts describe as “mushy” snapper indicate not all is well under the sea.
Along the east coast of the North Island, increasing numbers of snapper are being caught with unhealthy flesh, which experts say is due to their main food sources being depleted.
The usually hardy fish species is struggling for survival.
Analysis by the Ministry for Primary Industries (MPI) revealed a cause of the ailing snapper is due to prolonged periods of starvation.
Sam Woolford of LegaSea, a not-for-profit organisation focused on restoring coastal fisheries, said this signalled a severe imbalance in coastal fish populations.
“Snapper are known as the scavengers of the ocean, because they are one of the least fussy fish when it comes to what it eats, yet they are not getting enough food to grow and develop into healthy fish,” he said.
Key species in the ocean food chain, such as mackerel, pilchards and other baitfish were being overharvested by purse seiners (a large curtain net that surrounds large schools of fish) on the northeast coast of New Zealand every year, Woolford said.
“These are the primary sources of food that snapper and other fish need to survive.”
The National Institute of Water and Atmospheric Research (Niwa) was contacted earlier this year by both recreational and commercial fishers reporting white, soft, and “mushy” flesh occurring in 10 to 50 per cent of wild-caught snapper.
Recreational fishers who spoke to Niwa said the condition had had a sporadic presence in the last decade, however there were concerns about the increasing prevalence of the mushy flesh.
Analysis and observation of the snapper by MPI suggested the affected fish had undergone a prolonged period of starvation.
The problem is widespread. At Westhaven Marina, one in five snapper presented at the Kai Ika Project filleting station has mushy flesh.
While the government and scientists cannot find a definitive cause for these signs of muscular atrophy, tests indicate a degraded ocean environment and depleted food source are contributing factors.
Fishing methods, including bottom-trawling, which involves dragging weighted nets along the seafloor, are still permitted along the east coast.
The method is known to damage ecosystems that are home to crabs, mussels, invertebrates, and other species - key food for snapper and other fish.
Ongoing use of scallop dredges and over-allocation has also led to the emergency closure of the scallop fishery in Coromandel.
Bottom-trawling is rated as the third highest human-induced threat to the marine environment, Woolford said.
“Mushy snapper highlights a fish population that is seriously unwell and there is a genuine and growing concern among many people who depend on the ocean for their livelihoods about what this means for New Zealand’s favourite fish.
“For many Kiwis, snapper symbolises a classic summer day out fishing followed by a delicious meal with whānau and friends. But while mushy snapper is edible, they’re not appetising.”