Yellowfin Tuna

Yellowfin tuna are a torpedo-shaped fish, with dark metallic blue back, distinctive yellow sides, and a silver belly with many vertical lines. They have very long anal and dorsal fins which are bright yellow, which give the fish its name.

They can live up to 6-7 years of age.

They’re a migratory species, travelling long distances and are commonly found throughout the Pacific, Atlantic and Indian Oceans. They can be found at depths up to 250 meters.

Like other tuna species, they form schools by size, with juveniles commonly forming schools with skipjack tuna and juvenile bigeye tuna. But once they grow to over 40kg in size, they’ll usually travel alone.

Once they reach maturity at around 2 years old, they can breed all year round in tropical waters, and seasonally in subtropical waters. The peak spawning period in the southern hemisphere happens in summer and happens almost entirely at night.

Yellowfin can grow to over 200kg (440lb) and 2.4 meters (7’10”) in length. In Australia, yellowfin are most commonly caught around 15 to 50kg, and anything over 100kg is a magnificent catch. While in New Zealand, you’ll commonly catch yellowfin around 15 to 45kg. Anything over 70kg would be classed as an incredibly big fish.

AUSTRALIA‍

While you can find yellowfin tuna anywhere in Australia, they are most commonly found off the east coast of Queensland and NSW, and around Victoria. You’re less likely to find them along the south coast or around Tasmania.

Yellowfin tuna prefer the warmer currents, which are usually offshore, but they’re known to move inshore where deep water comes close to the coast. Jervis Bay in NSW is a common spot for this to occur, particularly during summer.

Exact fishing locations for yellowfin depend greatly on the water conditions. Current direction, speed and water temperature all play a part in pinpointing where you’ll have the greatest chance of finding them. Intel from local commercial fisherman, and apps can help you. As does understanding the temperature breaks and slack in the current, and being able to identify where the bait is likely to pile up as yellowfin will target these areas so they can feed.

Most Australian states have different size and bag limits for yellowfin tuna. Please ensure you check with your local state fishing authority before heading out to target this species.

VICTORIA‍

In Victoria, yellowfin tuna can be caught all year round. Historically their peak time is in colder months usually between winter and spring, however, anglers are frequently catching yellowfin throughout summer as well. Areas such as Portland, Port Fairy and the Bass Strait are common areas to target yellowfin, but can be dangerous waters which can present challenging conditions to reach. Avoid windy and rainy das which will bring swells to these areas.‍

NEW ZEALAND

In New Zealand, yellowfin can be caught in most North Island waters, however the biggest concentration of tuna activity is found in the Bay of Plenty region. Yellowfin will arrive around late December when the offshore waters start reaching 19-20 degrees (Celsius) and stay in the area until around April. You’ll commonly find them near the port of Whakatane and along the East Coast, down to Te Kaha and Waihau Bay. But you'll also find them along the North Island’s West Coast as far south as New Plymouth over the summer months.

You can find them in water as shallow as 90 metres, and right out over the shelf in the blue water. Yellowfin tuna tend to follow the warm water and will only hold in an area if there’s a good amount of food available.

Yellowfin tuna can be caught using a range of techniques, depending on the location, size, and general feeding behaviour. They will often be chasing schools of baitfish, which you can use your sounder to identify. Also keep an eye out for a congregation of active birdlife, including birds diving in the water to feed on bait balls.

When tuna strike, they hit hard and fast. Larger fish will sometimes hook themselves provided the drag is set right your reel will scream and line will peel off the spool at a rapid rate. If the line becomes slack during the fight, this usually means the fish is swimming toward to boat. Don't assume the fish has been dropped and wind up the slack as quickly as possible. Keeping the line tight will ensure you remain connected to your fish. Yellowfin tuna will give you a run for your money - they always fight hard. The fight will vary as they will move throughout the water column while also doing large circles under the boat, so make sure you have a good captain who can maneuver the boat and keep you in control of the fight.

TROLLING

Trolling probably the most common way to catch and target yellow fin tuna. It allows the angler to cover lots of ground, while searching for these schooling pelagic fish. The best way to troll for tuna is with a spread of skirted lures, which can range from 6 to 15 inches long. Generally, you have five lure positions in which you stagger the distances of each lure behind the boat, so they don’t get tangled when you make tight turns and circles.

These positions in order of distance away from the boat are: short corner, long corner, short rigger, long rigger, shotgun.

When trolling for yellowfin tuna, following the ocean currents, temperature breaks, eddys, and upwellings is very important. Before choosing where to fish/troll, it helps to get a membership for an ocean currents/temperature website, so you can look up the most productive looking water immediately before you go fishing. You can then work out the exact GPS locations and focus your efforts in these areas.

The Flea XT, Maggot XT, Liquid Lunch XT, and Jetsetter Maxi lures, rigged with 200lb Tough Trace and a 9/0 or 10/0 game hook are the perfect skirted lures to target yellowfin tuna with.

Overhead reels are preferred and should be set up with braid backing and a mono top shot to increase the line capacity to the maximum. This is because big yellowfin can take very long runs at times. Either 50lb to 80lb Rainbow Elite 8x Braid backing combined with the associated line class of IGFA monofilament(24kg or 37kg).

‍LIVEBAITS, DEADBAITS,AND CUBING

On other occasions, the yellowfin tuna may not be feeding on the surface, but instead can be seen onthe depth sounder schooled up in mid water. They can be very fussy when theyare behaving like this and are likely to refuse lures.

At these times, dropping livebaits or dead baits can be a deadly technique. The first thing to do is setup acube trail, to attract the tuna to your boat. Do this by chopping up smallbaitfish into cubes and dropping them into the water in small amounts. You can buy big blocks of pilchards in 10 to 20kg amounts which would be perfect for a few hours. Then you can start to feed a livebait, a deadbait, or piece of bait fish down the berley trail you have created.

Ideally the outfit you're using should be predominantly braided line, so bite detection is enhanced and with the lower diameter the baits will be able to float down the water column quicker, and more naturally.

LIVE BAIT

Catch your baitfish by first sounding up a big school of likely looking bait using your depth sounder, then dropping down our ‘Midnight Mackerel’ sabiki bait rigs. Retrieve the bait jig slowly using a jigging up and down motion, where usually the baitfish will hit the jig when you drop the rod tip. Keep your live baits healthy in a live bait tank, or a bucket but make sure you keep replenishing the water.

Hook a small baitfish (redbait or mackerel) through the nose on a 6/0 or 9/0 LB Series hook. These are small hooks which allow the baitfish to swim but are heavy gauge and very strong. They’re also carbon hooks so they can rust out if you plan to release the tuna and can’t remove the hook.

Rig the hook on 80lb – 130lb Tough Fluorocarbon which is hard to see in the water but very tough and abrasion resistant.

DEAD BAITS

Rig up a dead bait the same as you would a live bait (i.e. a whole dead bait fish). They can be cast into a bust up or simply floated down the cube trail.

CUBING

This is similar to dead baiting, but instead, use a chopped up piece of bait fish and put the hook through it, replicating the cubes of baitfish you are using as berley/cube trail. Set this up the same as you would for live or dead baits.

• When you get a hook up while trolling, maintain the boat speed for a few more seconds to try to get multiple hook ups. Yellowfin tuna are a schooling species so if you have got one strike, there is likely to be more fish in the area
• Sign up to a sea surface information website so you can get up to date information on the associated currents and temperatures in the areas you want to fish. This will assist you in fishing in the most productive areas
• Make sure you are fishing during the productive times of the day, early morning or late afternoon, as well as during the tide changes. These can be peak feeding times and may be the difference between coming home with a feed of fish, and not catching anything!
• Keep a close eye on what the birds are doing in the areas you are fishing. They are much more effective hunters than we are and will be in the area where the fish are well before you see them. Depending on the species of the birds, this can also tell you whether the baitfish are big or small. Get to know the sea birds in your local waters.