Fishing: Helping hand for an ocean predator

Omapere fisherman John Pattinson revives a 90kg striped marlin after it has been tagged, before it is released. Picture / Glenn Jeffrey

All the power of one of the sea's most spectacular predators, a striped marlin, is held in check as it recovers from being caught before being tagged and released.

It's becoming a familiar pattern, as big game fishermen head for a record year, thanks to a rise in fish numbers and the warm weather.

Herald photographer Glenn Jeffrey captured the dramatic picture as the fish was being held by fisherman John Pattinson - that's his gloved hand around the bill.

On the fish's right rear and left shoulder were circular scars where "cookie-cutter" sharks had torn out chunks of flesh, with barnacles growing in the shoulder wound.

Recent good weather has game fishers enjoying a marlin bonanza. Prolonged easterlies have allowed boats to get off the west coast. This fish was one of 89 recorded as weighed or tagged and released at the Hokianga Big Game and Sportfishing Club in the past month.

Marlin and yellowfin tuna have been caught in large numbers from New Plymouth, around North Cape, to Napier as weather patterns have pushed the warm "blue" water that the fish prefer close to both coasts, putting them within reach of anglers in small trailer boats.

Scientific study indicates that the marlin fishery is recovering well from the damage done mainly by Japanese long-liners after they moved into the southwest Pacific in the 1980s. After regulations were changed to prohibit long-liners from keeping marlin caught in NZ waters, the numbers and average size of the fish began to increase.

Last season, 1023 striped marlin were tagged and 592 landed - eight times the total caught in the mid-80s.

Massey University, with backing from Stanford University in the United States, is embarking on a world-first satellite tracking programme, tagging marlin in the Bay of Plenty with tags which will send data each time the fish surfaces. The aim is to find out more about what marlin do and where they go in New Zealand waters.

Fisheries scientist John Holdsworth of Blue Water Marine Research, who helps with the satellite tracking programme, says marlin recover quickly from the standard tagging routine provided they are not lifted from the water.

He says they do not have the parts of the brain that produce feelings of pain in humans or the "cognitive power" to turn that to anguish and agony.