DoC says the stranding at Ninety Mile Beach is a natural phenomenon that sometimes happens on Northland's coastline. Photos / Rachel Arcus
DoC says the stranding at Ninety Mile Beach is a natural phenomenon that sometimes happens on Northland's coastline. Photos / Rachel Arcus
Conservation officials say nature, not something sinister, caused a massive number of small fish to beach on a popular stretch of Far North coastline.
Hundreds of fish believed to be koheru (Decapterus koheru) stranded in the shallows and on the shore of Ninety Mile Beach/Te-Oneroa-a-Tōhē this month.
Department of Conservation (DoC) operations manager Kaitaiare Meirene Hardy-Birch said the stranding was a “natural phenomenon” that occasionally happened along Northland’s coastline, usually in autumn.
Ahipara residents shared photos and film clips of the sight on social media.
Some said they had seen similar strandings before, as much as twice a year and usually coinciding with a king tide and a full moon such as it had this time.
DoC says the stranding at Ninety Mile Beach was a natural occurrence. Photo / NZME
Residents said it was a good chance to get free bait for their freezers and an immediate meal.
Others were sceptical about taking the fish, fearing the stranding might have resulted from some disturbing deep-sea occurrence. Some were concerned the fish might have been bycatch dumped overboard by a commercial fishing operator.
According to online sources, koheru are considered by fishers to be the ultimate baitfish – big enough to lure big game fish, but small enough for most kingfish and large snapper to swallow.
About 500 fish, also thought to be koheru but bigger than those that came ashore recently at Ninety Mile Beach, were found stranded on the Mount Maunganui beach in June 2002. Photo / BOP Times
An Ahipara resident told the Northern Advocate a kilogram of koheru – about half a bucketful – usually sold for about $16.
Hardy-Birch said the natural phenomenon happened when large predator fish – such as marlin and kingfish – chased and herded smaller fish into tight bait balls before attacking them.
“In their attempt to escape, the smaller fish sometimes leap out of the water and can end up stranded on the beach.”
She said these events had been observed by local fisheries each year. In 2018, a similar event at Karikari Peninsula was captured on film.
“While some people may refer to these fish as ‘suicide fish’, this is simply a result of natural predator-prey interactions.”
Hardy-Birch advised caution when it came to eating the stranded fish.
“Unless someone witnessed the event and can confirm how fresh the fish are, it’s difficult to determine how long they have been on the beach and whether they are still safe for consumption.”
Ministry for Fisheries regional manager fish compliance North Andre Espinoza said beached fish should not be eaten because they could be unsafe.
He said the ministry had no information on the cause and fishery officers found limited commercial fishing activity in the area at the time of the stranding.
“The fish are most likely jack mackerel,” Espinoza said.
Sarah Curtis is a general news reporter for the Northern Advocate. She has nearly 20 years’ experience in journalism, most spent court reporting in Gisborne and on the East Coast. She is passionate about covering stories that make a difference, especially those involving environmental issues.