Southern bluefin tuna season is in full swing across southern Australia as the fish migrate along the coastline and while trolling has long been the preferred method for targeting blues, the popularity of casting to them is quickly rising. Scott Gray explains.

While southern bluefin tuna can be prolific on the continental shelf at this time of year, the fish often push in close to shore in late autumn and early winter which provides excellent fishing for small trailerboat anglers. Trolling is a very traditional and effective method for locating and catching tuna; however, I rarely employ the method at this time of year.
It’s a great way of searching for fish when their presence is not known from the surface, but when the fish are feeding on top, you just can’t beat sight casting for them with lures on light spin tackle. The strikes are visual, explosive and it’s a proven method for achieving consistent results on days when the fish are challenging. Most of the school fish range from 8 to 22 kg and provide some of the best light tackle fishing going around.
Inshore fish are typically very active and feed on the abundant bait that can be found in shallower coastal waters. These food sources often consist of small baitfish which the bluefin can get very focussed on. This can make them finicky feeders at times. As the season progresses the fish can also become more boat shy as more and more anglers chase them.
There are plenty of benefits to casting lures at feeding fish rather than trolling over them and some of these benefits include the option of fishing lighter tackle, less chance of spooking the fish and being highly mobile.
Unless I’m targeting big tuna there’s nothing worse than using big heavy gold overhead reels to catch fish on. To me it really detracts from the sport that these school fish provide. Threadline tackle has come so far over the past decade and small lightweight threadline reels are capable of handling more than enough drag and line capacity to secure a good sized school fish. Another thing to keep in mind is that inshore fish are generally found in water less than 50 m, meaning there is no chance of getting spooled. If a fish rips plenty of line off you have the ability to chase it in the boat. A 3000-5000 sized threadline reel loaded with 150 to 200 m of 30 to 50 lb braid is more than adequate.

An underwater shot of a typical school sized tuna that slammed a 12 cm Rapala XXXRap casting minnow.

STAYING MOBILE
The mobility you posses when casting is second to none and if the fish are up and down a lot or moving quickly and you see some action off in the distance, you can capitalise on it by motoring up to the school before quickly firing off a cast. You will always beat trolling boats to the action which means you’ll get the first shot at the fish. Some days it’s just a matter of getting there when the fish are up so this is really important.
Positioning your boat correctly is also very important. While the fish will move in many directions, you will find that bluefin feed into the wind. With this in mind, the best place to position your boat is upwind of the schooling fish. This way there is less likelihood of spooking them. You will achieve a longer cast with the wind behind you and cutting the motor off to employ a silent approach can also be effective at times.
MAKE IT COUNT
Let the fish come to you.
With light threadline tackle and wind assistance it’s quite easy to make a 50 to 60 m cast into a school, even with small sinking stickbaits.
When motoring up on feeding fish from behind, be aware of the wake coming from your boat. It’s often a good idea to take a wider berth from the school if you are behind them because even the boat wake can put flighty fish down before you get a chance to cast at them.
When you pull up within a good distance from a school there is less chance of spooking the fish and disturbing the feeding behaviour of both the fish and the bait on which they are feeding. This means you are likely to get multiple chances of a strike. If it’s busy and other anglers are doing the same thing then everybody can comfortably fish on a school at the same time.

Getting ready to land a solid bluefin tuna on a small stickbait.

SUITABLE PRESENTATIONS
Lure selection is very important. As mentioned above, fish can become fixated on small baitfish which are often balled up. Distance is also important so you need to select lures that are going to be able to cast a long way. This is where weighted or sinking stickbaits and metal slugs are of great advantage. Surface lures also work well at times, but are often lighter and difficult to work effectively when the sea is rough.
Metal slugs in the 20 to 40 g range are ideal for casting and are without doubt the heaviest lures for their size. They’re relatively inexpensive too. When retrofitted with a single hook they make an ideal baitfish imitation.
While I always have at least one metal slug rigged on a rod in the rack, I’ve been experimenting more and more with small sinking stickbaits and weighted bibbed casting minnows. It’s fair to say they have brought me more success over metals during the past couple of seasons. The range of small durable plastic moulded stickbaits and bibbed minnows on the market has increased significantly over the past few years and there are plenty of lures weighted enough to make a long cast while being durable enough to withstand the rigours of targeting solid fish on light threadline tackle.
The side-to-side action of a stickbait is very alluring and has proven perfect for when the fish are feeding just below the surface. You can also let the stickbaits sink below the school and retrieve them as fast or slow as you like. To work these lures, simply keep your rod tip down and give it a flick as you retrieve. You will be able to see the side-to-side action form the boat.

I typically retrofit all of my sinking stickbaits with single hooks as hook up rates are more plentiful and solid. They also cause less damage to the fish and are far easier to remove than trebles. Retrofitting your split rings is also important. Just don’t oversize them as this may affect the action of the lure. A good quality 20 kg split ring should be sufficient.
While I’ve had success with lures up to 15 cm, lures as small as 8 cm have brought about just as many bites. It really comes down to seeing what size range works best on the day. When you get it right it’s quite obvious as the fish will be all over your lures. Also, don’t worry about the fact that the lure is small as tuna have excellent eyesight. It’s truly amazing to see them swim up out of nowhere to smash the lure. Polaroiding tuna on the bait schools is one of the most exciting form of fishing as their dark blue backs ensures they stand out clearly. You can often see them actively moving around just beneath the surface and when several fish chase your lure in it really leaves you’re heart in your mouth. Just remember to concentrate when it does happen as it can be mesmerising.
When you do decide to chase some inshore school fish this season make sure you pack a light threadline outfit and try something different. Casting at feeding fish is not only productive on finicky fish but seriously gets the adrenaline pumping too.

Scott Gray is located in south-west Victoria, but spends plenty of time chasing fish across Australia and the South Pacific. While he enjoys all forms of fishing you will often find him spinning for big brown trout in the region’s rivers and lakes or stickbaiting for kingfish or tuna along the coast. He has a rich background in fisheries science and education and is currently sponsored by Rapala VMC Australia