Rare fish: Lizardfish hooked in Northland harbour excites experts

This bluntnose lizardfish was hooked in the Houhora Harbour. Photo / Nathan Cox

A Northland angler has landed a very ugly but very rare fish which has excited those dedicated to documenting weird and wonderful underwater species.

Nathan Cox was on the Houhora Harbour with two lines off his kayak when he noticed he had a fish on one of the softbaits he had cast into the incoming tide near a sandbank.

The 20-year-old butcher had already hooked a good feed of kahawai during the fishing mission on Tuesday and thought he had a little John Dory or a snapper. But when the experienced fisher and hunter reeled in the catch, it was a fish he had never seen before.

"Yep it was a bit of an ugly little thing," Cox saids. "I had no idea what it was and couldn't find anything that could confirm what it as."

The unfamiliar specimen had a very short snout and an oblique mouth with numerous fine, sharp teeth.

So he posted to Facebook page which was eventually shared to "What's That Fish NZ?" and got an answer identifying the deep water creature.

This bluntnose lizardfish was caught in the Houhora Harbour by Nathan Cox. Photo / Nathan Cox

Irene Middleton, of Ngunguru, is behind the Facebook page, and knew immediately it was a bluntnose lizardfish, with a scientific name trachinocephalus trachinus.

Records show the fish is usually found in tropical waters and has only been recorded once before in New Zealand, at the Kermadecs, in about 100m of water.

Middleton said the fish could be found lurking at depths of 388m, so to find it in the shallows of a Northland harbour was exciting.

She said not much was know about the species as they were rarely seen because they buried themselves in the bottom sediment with only their eyes exposed.

"This is a tropical species and the closest population is Lord Howe Island, on Australia's east coast, so this one has come a long, long way. Not much is known about them globally."

Middleton, a marine ecologist, has worked in Northland for a decade and is completing her Phd though Massey University.

In the last two and a half years of research for her thesis, focused on subtropical species in Northland, there have been 13 new fish species identified of which 11 have been in Northland waters, mostly at the Poor Knights Islands.

"Northlanders spend a lot of time in and on the water and they know when they see something unusual. Scientists can't be there all the time to identify these species."

It was great that fishers, divers and spearfishers reported their unusual finds.

"I'm just gathering all the information together and putting it into a form acceptable in a science forum," Middleton said.

Cox said while the kahawai he had caught were going in the smoker the lizardfish was neatly wrapped in plastic and on ice in the deepfreeze. He hoped to send it to experts at Auckland Museum when Covid-19 restrictions were over.

Tom Trnski,head of natural sciences at Auckland War Memorial Museum, said this was a very valuable fish for the museum and biologists in New Zealand.

Museums, and other agencies like Niwa and Manaaki Whenua Landcare, had a role in documenting the biodiversity of Aotearoa, he said

"Once in the museum, we will thaw it, take a tissue sample for future genetic analysis, photograph it, record all the details of where, when, who and how it was caught into our database, and then preserve the specimen to add to our collection," Trnski said.

All of the data and images would then be made available freely online.

"The result of this will be the range for the species will now extend to northern New Zealand and be visible to international online databases and researchers."