Fishing - Knowledge

Giant Trevally Fishing - Catching the Beast of the Ocean

2560 Views - 15 mins read

Every Salterwater angler dreams of a picture of a huge Giant Trevally on his lap.  It is a lifelong memory of a hard fought battle which can test the strength of the strongest of men. Popularly known as GTs, these beasts of the oceans are a prized game fish and draw thousands of anglers every year around the globe to plan deep sea trips of 1-3 weeks to have their fill of catching them.  How to catch a Giant Travelly? Read on to find out!

Catching a GT however, has lots of aspects associated with it. It’s not as simple as setting up the bait and hoping that the fish would come for it. The preparation is nothing less than going to war.  Top quality fishing rods with spares in case they break, top end heavy duty reels which are specially designed to stop big fish, high-end lure like poppers, stick baits and jigs which can empty your bank balance, toughest of line, leader and Hooks that will survive getting bent by the brute force exerted by the GTs.

 After collecting all this equipment, then there is the cost of travel to one of the exotic locations like Australia, the Andaman Islands in India, Oman or Seychelles, Hawaii, Ascension islands.  Further, there is the cost of stay of 1-2 weeks and hiring a charter boat with crew and captain to take you to the different reefs in the sea where the GTs can be found.  While the smaller ones can be found on the shores and estuaries, to find specimen sized ones you will have to venture out to the sea under expert guidance. 

After so much of planning and preparation, these GTs can give you hell and you might end up with sore shoulders from casting 150-200 gms poppers and stick baits continuously for hours, muscle and back pain from the brutal tug of war trying to stop a 100 pound GT from reaching the reef and cut off the line. But be assured the picture of a mammoth GT on your lap makes up for all the costs and the pain you would have endured.

Back Breaking GT Fight
Back Breaking GT Fight (Image Source:

For catching these brutes, the first thing that you will need is the passion as it will empty your pockets for sure and then you need to be in your top physical condition. In preparation, you would need to learn all about its features, characteristics and the best tactics that you can deploy. In this guide, you would be able to learn about the physical features of this species, places where you can find them, accessories you need to use and the best tips and technique to help you catch one. Let’s get started!

Know More Here:

Physical Features of the Giant Trevally Fish

The Giant Trevally, Caranx ignobilis (Known as ‘ulua aukea’ in Hawaii) is a species of very large marine fish which is classified in the Jack family, Carangidae. The giant trevally fish is distinguished by its rather steep head profile, very strong tail scutes and a variety of other more detailed anatomical features. They have fine scales for a better streamline, a ridge of plates at their tail’s base and a forked caudal or tail fin. 

Usually, these fishes are silver in colour with occasional dark spots. However, the males might be black once they are matured. They also have two retractable anal spines which aren’t connected to the anal spine. This is the largest fish in the genus Caranx and can grow to be as large as 170 centimeters (67 inches) and weigh approximately 80 kilograms (176lbs).  At times it can also weight as much as 200 lbs. 

giant trevally
Giant Trevally of the Blue Planet (source)

Particular Habits of Giant Trevally

In most of its habitats, the Giant Trevally is said to be an apex predator. It is known to hunt in schools and individually. This kind of species takes several fishes as prey. But, species like cephalopods, mollusks, lobsters, squids, octopus, mantis shrimp, eels and crustaceans contribute to a major part of their diet. The hunting strategies of this species are quite novel and include using sharks to ambush the prey along with shadowing the monk seals to pick off the escaping preys.


This kind of species is said to be rather aggressive in nature. The young Trevally cannot be recognized as a predator but it can hunt pretty well. A giant trevally is believed to be so powerful that it has the capability to bend the iron hooks so as to escape. When it comes to tackling a 200 lbs giant trevally, the task seems almost impossible. 

Swimming Distance Covered

These species are known to have the capability to swim large distances. However, during the full moons in summer, they migrate up to 30 kilometers in order to reach traditional spawning grounds. It is here that they form large aggregations.


The giant trevally fish is a recognized gamefish and an important species to the commercial fisheries. The professionals use lines and nets while the anglers use lures and baits to take the species. If we go by the statistics, the catch in the Asian area shows hauls of somewhere around 4,000-10,000 tonnes. Approximately 10,000 lbs of the species are taken in Hawaii alone each year. The dwindling numbers around the Hawaiian Islands have led to various proposals in order to reduce the catching of this species fish in this area. 

Where can Giant Trevally be Found? 

Most fishing enthusiasts often wonder as to where to catch giant trevally and how to catch trevally. Well, the giant trevally inhabits an extensive range of tropical marine environments. The juveniles can be found in shallow bays, estuaries, and lagoons while the adults can be found in deeper reefs, large embayments, and offshore atolls. The juveniles of this kind of species are known to live in water with very low salinity like the upper reaches of the river and coastal lakes. They often tend to prefer turbid waters. When it comes to giant trevally fishing, this kind of species is widely distributed throughout the tropical waters of Indo-Pacific region.

It ranges along the coasts of three continents and several hundreds of archipelagos and smaller islands. In the Indian Ocean, the species’ westernmost range is the coast of continental Africa, being distributed from the southern tip of South Africa, north along the east African coastline to the Persian Gulf and the Red Sea. It also extends eastwards along the Asian coastline which includes India, Pakistan and into Southeast Asia, northern Australia, and the Indonesian Archipelago. On the Pacific Ocean side, they are found in the islands of Hawaii. 

As discussed above, the GT’s can usually be found cruising near the shore and around the offshore reef structures like the atolls, coral reefs, drop-offs and pinnacles. One of the best trevally fishing tip would be to look for areas around the reefs where there are a large number of baits holding up, particularly the fusiliers around atolls and offshore reefs.  If you see a bait ball i.e. a large school of fish jumping above the water, it is a sure indicator of some large predatory school of fish (most probably GTs) which are rounding up the bait and picking them off one by one. 

GT Bait fish Fusiliers
Fusiliers - GT baitfish

Giant Trevally Fishing and Non-Fishing Season (Mating Season)

The giant trevally fish reproduces during the warmer months with the peaks differing by the region. Spawning generally happens at certain stages of the lunar cycle. This is when the large school assembles together so as to spawn over bays and reefs. There is a reproductive behavior which can be observed in the wild. This spawning season usually lasts for about four months every year. The fishes can grow comparatively fast and reach sexual maturity when they are about three years of age and have a length of 60 centimeters.

giant trevally in Indo Pacific Ocean
Giant Trevally are found in Indo Pacific ocean (source)

Giant Trevally Fishing Techniques  

With Ulua fishing, you need to be aware of the fact that the species of this kind takes whole fishes, dead or alive. They also take soft plastics, fillet baits and trolled minnows. However, the most exciting way to target them is on very large surfaces like the stick baits and poppers. 


This is the most popular technique to catch GTs. But first, you need to find them and that is usually done by boat pulled up in deeper water within the casting distance of an area where they can be found, like reef outcrop. Ideally hiring an experienced charter boat and captain, would greatly help in your GT quest.  Cast stick baits or poppers towards the edge of the reef and then work the lure back towards the boat. You would need to impart as much action to the lure as possible. Upon hookup, pull the fish off the reef as quickly as you can.  

GT Popping technique

When using poppers, cast them away and make sure that you are using hard sweeps to create the pops and the splash of water in front of the popper. This commotion will be heard and seen by the GTs and their natural instinct is to attack it furiously. The sight of a GT chasing and grabbing the lure is unforgettable.

Vertical Jigging 

In this method, you will be pulling GTs from a depth of 20-60 meters.  Heavy Jigs around 100 to 150 gms are used to reach the required depth quickly and PE 5-7 Jigging rods are used to jig them vertically from the bottom to the bottom of the boat.  The vertical jigging technique requires fast retrieval with some pauses in the middle.   A large variety of fish are targeted using this method with GTs being one of them. 

Bait Fishing 

A Giant Trevally fish generally responds to all types of marine water fishing techniques. The most popular techniques adopted by the fishermen are Jigging, fly fishing, trolling and bait fishing. However, Bait fishing with baits like eels or octopuses is also used where the fishermen set out a sinker attached to the baits with a strong metal ring and thinner line. A loud bell also at times gets attached to the rod. The fishermen during this time set their camp beside the shoreline and then wait for the fish to catch the bait. Fillet baits are another option that can be used. They work well but not as great as the live whole or dead fish caught on the spot.

Giant Trevally Tackle

When it comes to GT fishing, remember that each and every accessory that you are using is in perfect shape. If even one of the accessory let's say the lure or the hooks aren't in top condition, it’s absolutely certain that you won't have any success in landing a specimen sized GT.  

Rod and Reel 

As discussed above, when it comes to Ulua fishing, these fishes are very aggressive and are very heavy. Therefore, you would need a strong and lightweight graphite rod that is perfect according to the size of the lure and the region where you plan to catch the Giant Trevally Fish. The minimum rod length for casting would be 7 ft. and you could use anything up to 9 ft. Rods that have been rated PE 6-10 would be a good option
Along with that, using a superior quality reel would be recommended. Most fishermen pick reel series of 10000- 20000 of Shimano Stella or 5000-6500 series of Daiwa Saltiga. There are various popular brands in the market that offer excellent quality rods and reels which you can choose from. If in doubt, it's best to talk to the GT charter captains who can guide you what to purchase. 


You need to have the best trevally lures when attempting to catch these big fishes. Large poppers like Black Jack Cubera, Dumbbells, Temple Reef Ballista Bulls, Hammerheads, Tuna bombs, Carpenters and Fishermans are considered to be the best lures. Large stick baits like the Black Jack Ulua, Temple Reef Lambo, Daiwa Dorado, Shimano Ocea would be some of the best options. 

GT Poppers and Stick Baits

The Giant Trevally Fish is fearless and very powerful and would generally try to gobble down the lure. If the lure is wooden, there are high chances that the fish would try to escape by crushing it with its bite strength. Hard plastic lures are a good alternative must be used


GTs are notorious for bending hooks and you would want to use a very large sized, heavy and solid singles or treble hooks.  Singles are preferred mainly to avoid damage to the fish. Most of the GT fishing is catch and release and so care must be taken that they are released with minimal or no damage.  Giant Trevally Hooks that are most effective are 5/O treble hooks. The popular brands are Shout Kukado, Gamakatsu GT Recorder and Owner. You may also choose to crush the treble to make it barbless which makes hook removal easy.  Instead of the traditional method to attach two trebles to a lure, there is a trend of putting a size 5/O treble on the belly of the lure and a size 7/O or Size 9/O single to a tail.

GT hooks

Line and Leader

The best of the best is required here.  While small GTs can be got from lower rated lines and leaders too, but if you want that monster GT on your lap you should get at least 100 lb test braid line and 150-200 lbs test leaders from top brands in your region. 


Two knots are required which should stand the test of the GT force, one is a braid line to leader knot - the best knot for this is the FG knot.  You can find youtube videos of how to tie FG knot.  Practice this knot a lot before going out to the actual GT fishing trip.   The great advantage of this knot is the slim profile and can pass through the rod guides easily and the second advantage is the strength of this knot as it will not slip in any stress condition if properly tied. Sometimes the FG knot is not closed properly and this can lead to the knot opening up and you will lose all your expensive terminal tackle and lures and the fish.  So it is imperative to practice this, again and again, till you are confident of doing this.   

FG Knot

The second knot is for tying the leader to the swivel.  This can be your regular clinch knot or the improved clinch knot.  Again make sure it is tied properly and give it a few good tugs to see if it is slipping. 

Terminal Tackle 

Heavy duty Split Rings are required to attach the hooks to the lure.  These should be at least 200-300 lbs test.  To attach the leader to the lure you need a 300 lbs test ball bearing swivel.  This is required to prevent line twisting and hook and lure damage when the GT is doing its death roll. Good brands here are NT Power Swivels and Owner Hyper wire Split rings. 

GT fishing Split Rings and Swivels

Accessories and Tools

Other than all of the above, for catch and release of the fish, it would be best to wear a pair of long-nosed pliers on your belt. This would allow you to easily remove the hooks without hooking yourself. 

Split ring pliers which can open a size 10/11 split ring is essential when changing the hooks on your lures.  

GT fishing accessories and tools

Good quality popping casting gloves are also useful in avoiding blisters when you are casting heavy poppers for long hours or wish to grab the GT for a picture.

Another important accessory is a Fish fighting belt. The backbreaking fight requires your rod to be positioned in a stable manner with all your focus being on pumping and reeling.  

Tips to catch Giant Trevally: Don't Miss These!

  • If you notice that the water is calm, using poppers would be the best option. Bigger sweeps and slower retrieve would allow the rod to move more water.  Remember bigger poppers will attract bigger GTs.  A monster GT would consider if it is worth spending its energy on the chase.

  • When starting out, ideally have 2-3 anglers in the group to be popping together using big poppers to attract GTs. More the noise faster will be the strikes

  • The drag has to set tight as the objective is to stop the GT in the first run itself.  Since most of the strikes will happen above the reefs, the GTs make a straight dive for the reefs after getting hooked and once there, there are high chances of the line breaking off after contact with the rocks. 

  • When the lure hits the water, there are high chances that you might get a GT strike if they are there in the vicinity and as the drag is set high, you have to be prepared for the strikes and keep your footing firm else you can lose your balance.   

  • You need to remain patient when catching the Giant Trevally fish. When they are around, do not rush to retrieve. If you notice that the fish is neither close to the lure nor hitting the bait, you need to stop whatever you are doing and look at changing your tactics.  Experiment with colors and different types of poppers and stickbaits. 

  • Hook setting - This one is very important - when the GT catches the lure, a few hard tugs are required to ensure the hook is set. A lot of times the GT is only holding the popper or stick bait in its mouth tightly and therefore the tugs are required to let the lure slip its bite and allow the hook to set. If this is not done the chances are that the GT will open its mouth and escape after realizing that the lure is not edible. This is also why wooden lures are not recommended as the GT will sink its sharp teeth into the wood improving its grip and making it harder for setting the hook.

  • Avoid starting the fight without making sure that the hook is set. There is a tendency among anglers to start pumping or trying to put the rod butt in the fish fighting belt before setting the hook. Lots of GTs are lost this way.

  • After setting the hook - continuously pump the rod up and reel in the slack line when the rod is going down.  Don't let the GT have a good run, tighten the drag more if required.

  • Do not compromise with the tackle, the best of the best of tackle is required to pull out a monster Giant Trevally. Hooks bend, swivels break, split rings open up, knots slip, leaders snap... there are too many variables you are fighting against. 

  • If the hookset happens very near the boat, most likely the GT will dive under the boat.  If you see you have hooked a monster Giant Trevally, open the bail arm and allow it a minimum run, else you can kiss your rod goodbye. 

  • After the fight when you bring the GT near the boat, have a partner grab the leader and tail to pull it in.  Take quick pictures, before or after removing the hooks, and then release the GT by throwing it face first in the water.  This is required to ensure the water rushes through its gills and helps it revive faster.  Putting it gently in the water is not a good practice as it will not give the GT the required oxygen to revive quickly. 

Summing Up 

When targeting these Giant Trevally fish you need to remember that you might not succeed the very first time. It takes time and a lot of patience especially when you wish to catch big fishes. Keep trying or ideally go under the guidance of an expert GT fisherman or a charter service and you will definitely catch your first big one. 

Have you ever tried catching these big fished or did manage to catch one? Do you have any questions that you would like us to answer? Feel free to share your thoughts in the comments sections below. We are always eager to hear from you!

And we will leave you with a video to show why GTs are the baddest and the maddest fish of the ocean. 

Cover Source

Get Started
688 Views - 0 Comments
10 Mins Read