Description

Southern bluefin are a large tuna species, highly desired not just by New Zealand anglers but also by seafood connoisseurs around the globe. In fact, the value of the species is such that commercial catch limits are managed by international convention!

Bluefin are muscular, streamlined, fast-swimming fish with relatively short dorsal, pectoral, and anal fins that fold down, affording these fish almost bullet-like hydrodynamics. Their body colour is blue to black on the back and silver to white on the flanks and underside, and their rear finlets are yellow-edged, sometimes leading to confusion with bigeye tuna.

Bluefin are widely distributed throughout the Southern Hemisphere and have complex migration patterns, with fish reaching New Zealand generally adults. The southern bluefin tuna is an opportunistic feeder, preying mainly on squid and various fish species.

The recreational southern bluefin tuna fishery in New Zealand has exploded in recent years in both the North and South Islands, largely thanks to commercial longliners sharing their knowledge.

Where to catch

Waihau Bay is now synonymous with the winter run of southern bluefin along the continental shelf. But East Cape is not the only base to fish from; from mid-winter on, the tuna head up the North Island’s eastern seaboard and are regularly targeted out of Gisborne, Whakatane, Tauranga, Coromandel, and further north. Anglers generally have to travel out to approximately 1,000-1,500m depths to find the bluefin – the fish tend to concentrate on areas of upwellings around the continental shelf edge or offshore seamounts.

Bluefin are also increasingly being caught on rod and reel in the wild waters off the Fiordland coast over the warmer months. Keen anglers fishing out of Doubtful and Milford sounds have clued up to the presence of bluefin schools here and fish are being caught on a variety of techniques –sometimes very close to the shore!

When to catch

With an extensive temperature range, southern bluefin are available to Kiwi anglers for a substantial portion of the year – although this varies depending on location. Schools frequent the west coast of the South Island from January to April, then show up off Napier and Māhia in April/May before moving up to Gisborne and East Cape. The prime period off Waihau Bay is usually June and July, while out wide off the Coromandel and Great Barrier sees a run of fish in late winter. 

Although the winter weather conditions generally dictate recreational fishing opportunities for bluefin, many crews prefer to fish around the full moon. Time of day is also an important consideration, with many bites happening at sunrise or sunset while the fish feed actively near the surface.

How to catch

Most bluefin fishers run a spread of small game lures featuring different head shapes: bullet, straight running pushers and aggressive slant-faced lures in the 6-10” size range. Preferred colours are anything natural as a first choice, followed by lumo and then orange, rigged with 8/0 and 9/0 double-hook rigs on relatively short 200lb fluorocarbon leaders to handle chafing on the often deeply-hooked fish. The rule of thumb is to run your spread at least one wave, if not two, further back in the wake.

Trolling speeds are generally slower than for marlin fishing – around 5.5-6.5 knots – and the use of squid daisy chains, spreader bars, and bird teasers is recommended.

Southern bluefin are often found in small schools, so on hooking up, many crews keep the lures in the water and the boat moving forward for a little way before clearing the gear to increase the chances of multiple hook-ups.

Because of their schooling nature, when surface bluefin action is encountered, they can be effectively targeted on stickbaits, poppers, jigs, and fly – or a good ol’ fashioned chunk trail.

Make sure to take a decent insulated body bag and lots of ice bluefin fishing to keep the tuna in prime condition before breaking down.