I always look forward to fishing the month of September in SEQ as it usually signifies the start of Jack season for me. Jacks usually start to school up at this time of year in warmer water with plenty of bait present. Trolling is a very productive method of angling during this time and it is quite easy to master the basics. It is a great way to introduce family or friends to sport fishing and when fined tuned to your local waterways regular catches should be expected. Whilst trolling for mangrove Jack, bi-catch can sometimes make up for the majority of your haul and its funny how fish that would normally qualify as a trophy all of a sudden seems so lack lustre. Species like flathead and bream are a very common capture but you can also expect pelagic fish like GT’s and tailor in south east Queensland and welcome by-catch like barra in the north.
Many serious anglers look upon trolling as amateurish however, there is lot more to it than many perceive and trolling will frequently out fish any other method of angling for jacks when executed correctly and at the right time of year. I have on many occasions caught double figures in a single session working a tide change where Jacks are schooled. In the early days when I first started experimenting with lures I occasionally trolled up the odd jack and a few other species in the Gold Coast canals, on the Tweed rock walls and on the Fisherman Island rock walls in Brisbane. I didn’t really know what I was doing except that I had to keep the lure near the bottom. Over many years this has proved to be the most important factor for success.
From May through to the end of August I do not consider jacks a viable target species and most captures taken in these months by anglers are by-catch when targeting other species. When the first cold snap hits coming into winter the water drops suddenly and they almost go off the bite at the click of your fingers. Jacks respond well to sudden rises in the water temp and react badly to sudden drops in temperature just like the Barramundi. I have targeted them in winter with success after a few consecutive days of hot northerly winds and overcast conditions but the feeding spree is usually short lived and inconsistent. Rock bars and groins exposed at low tide in winter heat up quickly under the sun and sometimes have jacks hugging them tightly for warmth when the high water covers them back over.
Coming out of winter when the water temperature rises back up to 20 plus degrees they go in search of food just like a bear coming out of hibernation. The quicker the water warms the more energetic, curious and troublesome the fish become. This is generally when the waterway suddenly rises 2-5 degrees literally in a week.
I usually start searching for jacks by trolling in late August or early September and persist through the slow days as I know it is going to eventuate. Last year in the Noosa River they came on hard in the last week of August, the year prior it was in the first week of September. Once I find them I start to target them by other methods and push the limits to keep it interesting.
Finding a prime trolling location
Jacks are a tropical species found in the northern half of Australia’s estuarine waterways. The creeks and canals that have trolled best for me are those that have an average low tide depth of approximately 1.8-3 meters and decent structure being either heavy mangroves, rocks, jetties or timber along its banks. If there is too much thick structure scattered over an intended troll path, trolling may become frustrating with continuous snagging. You will hook onto the odd patch of jacks in deeper holes and deep rock bars but the shallower creeks are much more predictable, reliable and thicker in numbers most of the year. Over many years the two systems I have had most experience with have benn Cairns Inlet and the Noosa River. I discovered trends for jacks to school in particular areas early and late in the season being September to October and March to April. These areas generally had a shallower mean low tide depth of around 2 meters with shallow flats in the vicinity and I assume the jacks were schooling due to the warm water run off from the flats and abundant bait sources possibly congregating for the same reason. Trends will emerge in any system and the only way to discover them is by putting the time on the water. Get to know your local creek and always keep a keen eye on your sounder because the more you troll it the more refined you will become. When working a new creek take the time to map out your troll path concentrating on the channels, structure and mangrove undercuts. Don’t be afraid to troll right up against a deep bank.
Tides & Times
The tides and moon phases influence the feeding patterns of mangrove jack quite considerably. They can be caught day/night, low or high tide but if you want to be constantly successful attention to the tides and applying the right techniques for those tides makes all the difference.
When trolling the optimum luring time of the tide for me has been 2 hours before the low tide and through the tide change to when the water starts running back in at full force. When the water starts to slow the jacks usually come out to play and when it turns and starts to pick up speed they will generally go off the bite or find shelter out of the current. Trolling on the high tide change will also catch big jacks but not usually to the same extent.
Over many years of fishing this technique I would have to say the most productive days trolling have been the 5-2 days leading up to the new and full moon. This is when the tides are more severe and the run is harder in between changes.
While trolling first and last light is not a crucial to finding success, combining these times with a low or high tide change is very productive. When the high tide lines up with first and last light I prefer to chase them with other methods as they venture up onto the flats or into shallower snag ridden areas that they would not normally venture into under less cover. Trolling at night produces some thumping fish but I find it less productive in regards to quantity of fish. For obvious reasons trolling at night can be difficult unless you know the area you are fishing very well.
About 30cm off the bottom is the perfect position in the water column for the lure to be tracking. The occasional puff of sand or bump over structure doesn’t hurt and in fact can be a turn on, however, you don’t want to be constantly on the bottom or you’ll end up retrieving a lot of lures with a tackle back. Lifting and lowering your rod as you watch the sounder will raise and lower the lure in the water column to a certain degree. The lighter the line and the more line you let out the deeper it will troll until it reaches its optimum depth. The diameter of the leader and main line play a crucial part in how deep a lure will track. By adding thicker, longer leaders you will decrease the depth a lure will track.
Always stagger your lures out the back when trolling for two reasons; the first is to cover as much area as possible and the second is to avoid fouling on bends or when turning. If you’re spread has lures that run at different depths place the deeper divers in close and the shallower lures further back but ideally you want to use lures that swim at similar depths which is just off the bottom. If trolling over a muddy or sandy bottom a deeper diver can be set in close to puff up the bottom and draw extra attention and on steep sloping banks a shallower lure can be trolled on the bank side and a deeper lure on the away side. It’s possible to troll 3 lines down one side when targeting deep mangrove undercuts or steep snaggy banks if you stagger them correctly. I wouldn’t recommend trolling more than 2 lures for a novice fishing solo as multiple hook ups although rare can be absolute mayhem. When chasing Jacks I always troll at idle speed (1.6-2.2 knots) and prefer to use a 4 stroke motor, however, in saying that I still catch more than my share with the 60hp two-banger that I currently own. The noise difference in motors doesn’t seem to deter them as much as I first thought many years ago. I occasionally troll with an electric motor however there is no significant increase in numbers caught and it is generally a little more difficult. An electric is great in smaller more constricted creeks but the size of fish also seems to suffer in these locations.
When trolling for Jacks a 3-6 kilo spin or bait caster combo loaded with 10-20lb braid will do the job fine depending on your preference. Once you start using a main line over 20lb to its limits, lures, hooks and split rings start failing so in my opinion fishing this heavy is pointless. I use reels in the 2500-4000 size with a smooth drag of at least 3kg. Rod preference is of 6’6 to 7’3 feet long with a softer taper although there is no real need to be all too fussy. Use the best gear you can afford and look after it as the last thing you want is a reel seizing when a big fish hits or a broken eyelet slashing your braid. However, in saying that a maintained trusty old Abu full of 20lb braid and the ever faithful ugly stick (every old school lure fisho has owned one) was ample to knock over the majority of fish I encountered when first starting out.
When trolling, back the drag off a little, especially if the rod is in the holder because they hit pretty dam hard. There’s a lot of inertia behind the boat and when a big Jack hits a trolled lure the boat keeps going, the rod bends a little and something has to give. I’ve seen rods with locked drags disappear out the back of the boat breaking plastic rod holders never to be seen again and have also seen a locked rod ripped from a clients clutches. Jacks don’t take long blistering runs but you will need to lock the thumbs down and pull the bigger fish up short if they head towards structure in a hurry. You might pull a few hooks but it’s better than losing a few lures.
For leader I recommend about 100cm of 20-30lb fluorocarbon attached via a double to the main line. No swivel! I prefer to use a perfection loop but a snap clip can be used for ease of changing lures. If I want a particular lure to swim a little deeper I will go as light as 12lb leader in open, relative snag free water.
Most of the hard body lures I use for Jacks are around 5-10cm long but I also use up to 20cm and longer at times. A pattern will start to evolve through experience in your local waterway however it is always changing and at times hard to stay on top of. The main factor is to use a lure suited to the depth that you are fishing. Using a combination of sizes is great to start with. Use SHARP strong hooks; this is very important for your hook up rate and also sticking the fish till landed. I have been lazy many times and used old rusty hooks and it has cost me fish. Recently I have been replacing the rear treble hook with a single hook to make release easier for the fish and myself. I’ve seen Jacks caught on every colour of the rainbow however I tend to favour gold in clear to medium discoloured water and green or pink in dirty water. On some days one particular colour will catch every fish and on others they’ll hit anything you throw at them. I always say what works today might not be in season tomorrow however it’s still a good place to start.