Bay of Plenty: Shining surprise

The skipper shouted "Double strike," as two of the four trolling rods bowed and the reels screeched. Then, when a flash of iridescent green and yellow speared the water: "Mahimahi, yahoo." That was in the mid 1970s and we were trolling at Rangatira Knoll, about 30km north of White Island in the Bay of Plenty. In those days this water rarely saw a boat or a lure. We scored a good yellowfin tuna on the first pass over the knoll, then the double on mahimahi.

That had everybody excited, for mahimahi were largely unheard of in New Zealand at the time. They were tropical fish that you found in the Pacific Islands or Hawaii.

Our pair of mahimahi were impressive specimens and we marvelled at their shimmering colours, lean powerful lines and blunt heads.

They put up a good account of themselves but were no match for the heavy marlin gear.

"That will be a New Zealand record," said the skipper of the 22kg bull mahimahi I had reeled in, mainly because the category was vacant at the time so any catch would qualify. But I am not interested in records, particularly when the fish did not exceed the 24kg line weight, so we did not apply for a record. The catch was more of an accident than any measure of angling skill.

But we did enjoy the pan-fried fillets, as mahimahi has to be one of the loveliest fish on a plate.

Today mahimahi are a common catch, maybe because our waters are warming, or perhaps because our methods have changed and trolling lures is more likely to pick them up.

I put the question to Pete Saul, records officer for the Big Game Fishing Council, father of the marlin tagging programme and seasoned Tutukaka charter skipper.

"A bit of both really," Pete said. "We have had some warm years, and in fact there were a lot around this summer and last year, too.

"But I think people are more aware of them and are chasing them more actively. If they see something floating in the water they will go over and tow lures past it.

"We get a lot of small fish here so you need small lures because we are at the bottom fringe of their distribution." Mahimahi are found in tropical and subtropical waters and the name is a Hawaiian word that translates as "strong fish".

But they are known by different names in different countries, the most common being dorado and dolphinfish. Dorado has Spanish origins and refers to the changing colours as the fish dies. The dolphin reference has no association with the dolphin family of mammals so can be confusing.

Mahimahi are attracted to flotsam and can be found swimming around buoys, pieces of timber, clumps of weed and just about anything floating on the surface.

They are among the fastest-growing fish and only live to four or five years, seldom exceeding 15kg, and are distinguished by dazzling colours with golden flanks and bright blues and greens on the sides and back.

Mature males have prominent foreheads while females have a rounded head and are usually smaller than males.

They are fast swimmers, with a top speed of 50 knots, and as such are popular sport fish, performing well on light tackle and often leaping time after time.

They feed on small fish, squid, plankton and crustaceans. They can be caught on small lures and fly tackle and they love small live baits. Mahimahi are highly sought for sport fishing and commercial purposes around the world.

Fishermen in Aitutaki, in the Cook Islands, toss out small live bait fish to attract the mahimahi and catch them on a live bait hooked through the lips with a tiny hook. But they are not happy if you hook and lose a mahimahi. They claim that fish will then spread the message to the others and you won't get strikes. I have seen that happen more or less as they tell it.

There is another method of catching them throughout the islands, from Tahiti to Tonga, and that is with a harpoon. The fishermen use a long, narrow boat which they steer from the sharp prow with a long stick attached to an outboard engine while standing up and looking for mahimahi. They then chase the fish, which do not dive but swim on the surface, until they tire and can be speared.

The world record is a 39.91kg mahimahi caught in Costa Rica.