Sixteen years ago, as I made the move to Queensland, the goal of catching my first mangrove jack was nearly as important as finding a home. Like so many southerners wanting to catch their first, I had become somewhat obsessed with the look of these fish, and the stories of their aggression and power only added fuel to the fire. The brilliant red colouration and armour-like look suit this fish well as they simply know no limits when it comes to aggression. Mangrove jack are a stunning fish and pose serious challenges to all anglers.
Where Most Anglers Begin
As with any newcomer (or even seasoned jack anglers), when you discuss ‘mangrove jack’ your mind instantly drifts to a mangrove-lined creek where timber snags are screaming at you to cast. Casting lures in and around the mangroves is of course a seriously exciting way to target jacks and is highly successful. It is where these fish begin their life and grow to maturity before heading out of rivers and creeks to offshore reef systems.
As you travel further north throughout Australia you will start to find large numbers of juvenile mangrove jack throughout healthy systems and some seriously entertaining lure casting can be had. What must be pointed out, however, is that the bulk of the fish will be smaller and it can be incredibly difficult to nudge past that 45cm size range in the real tropical creeks.
Thinking Outside the Box
While snag bashing and edge casting will come to mind quickly, the purpose of this piece is to think out of the box and look at targeting jacks deeper down. In systems throughout South East Queensland, highly successful sessions can be had by concentrating on fish holding on structure deeper down. Rock bars, deep timber and drop-offs all provide ideal cover and ambush points for mangrove jack and it is here you can further tap into the habits of these cunning predators.
Before even thinking about successful tactics to tempt fish deeper down, you must have reasonable knowledge of tidal movement and how fish will react during the various phases. Water clarity and overall salinity levels will also play a vital role – if there are two things mangrove jack love, they are clean water and current flow. This is not to say you won’t catch jacks in dirty water, but generally speaking these fish do love cleaner water higher in salinity.
Your challenge as an angler now becomes to think like the fish. It is a phrase you have no doubt heard many times over, but nothing rings truer and it cannot be over-emphasised. A starting point to carefully consider is what rising and falling water will mean and what opportunities present themselves. A rising flood tide enables fish to move up and be among the snag-lined edges should they decide this is where they wish to be.
Many jacks will decide to stay deeper down and choose to feed more actively as bait fish are forced off the shallower grounds on the run-out phase of the tide. Several other factors such as water clarity and time of day also come into play here and will often dictate the fishes’ movement. As an example in my local system (Noosa River), what can often happen along the snag-lined banks is that general boat traffic (commonly heavy) will see the boat wake ‘muddy up’ the edges, making them quite dirty. Casting lures on the edges can be a very slow game as the bulk of the fish remain deeper and are very content sitting along the drop-offs and broken-up coffee rock below. Fish are also more inclined to do this if the sun is high and they are wanting more cover to ambush prey. The incoming tide can see fish feed more opportunistically and I have done reasonably well on this phase as the tide slows in its last two hours.
The run-out tide signals a different alarm bell altogether and in my honest opinion I can say that mangrove jack feed harder and more aggressively on a falling tide. As bait is pushed back out from shallow edges and mangrove flats, it is now that jacks hit the next level of aggression, into ambush mode. Facing into the current while holding on structure or along drop-offs, anything that passes nearby is fair game. Once again, water clarity is a factor to keep a watch on and in relatively shallow water systems (such as those throughout South-East Queensland), the water can often become rather dirty in the latter part of the outgoing tide.
When we use the term ‘drop-off’, we are not talking about a few isolated stretches where a sand bank may be visible, leading to an obvious drop-off you may associate with, say, flathead. We are talking about where the actual riverbank may be as shallow as half a metre in close and tapers sharply to form a steeper drop-off. In the shallower systems of Queensland, this drop-off may only be down to 2.5 to 6 metres and will extend the full stretch of your chosen part of the river. Mangrove jack love to sit on the drop-off edge as they can ambush prey running on the inside shallower ground running back with the tide and sink back to the comfort of the deeper water when desired.
I like to fish the drop-offs with plastics and my preference is for either a fish or prawn profile. No mangrove jack will knock back a prawn or poddy mullet and if your lure matches either of these in profile, you are on the path to success. In the boat my usual approach will be to spot-lock facing up current and work my plastic back with the outgoing tide. A plastic in the 4in size range is ideal and your jig head selection will need to be based on how much water movement you have. This can vary around the moon phases but generally speaking I will start with ¼[IG1] oz head and if need be, go heavier from there. You do want your plastic hitting the bottom and I have found it advantageous to double-hop my plastic quite aggressively for jacks and make that bit more noise down deep.
At times it may be necessary to fish your plastics as weedless presentations along the drop-offs. This will often be due to broken timber and submerged snags deeper down. Do not be afraid to rig plastics weedless as jacks smack them so hard, the hook point is exposed with ease. Weedless rigging can save you from a mountain of frustration if casting along snaggy drop-offs. My preference for weedless rigging is to take an unweighted weedless hook pattern featuring the twist lock keeper and simply crimp on a split shot sinker at the top of the hook. As you take your fish or worm profile soft plastic[IG2] , the weight will sit under the chin area of the soft plastic. Rigged in this fashion I find it very simple to generate an incredibly life-like swim from any paddle tail or prawn soft plastic.
Soft vibes are also worth a mention and are another seriously popular presentation along drop-offs. You will, however, need to drop and work these along the more snag-free sections or you will be cursing many times over during your session.
Rock bars are some of my favourite grounds to fish and are absolute magnets for jacks of all sizes. Common throughout South East Queensland, rock bars are made up of broken ‘coffee rock’, which is also oyster-encrusted and incredibly nasty terrain to extract fish from. Other quite monstrous rock bars also exist and certain systems hold rock bars that are seriously impressive and easily visible using modern sounders. My preference for lure casting along rock bars is once again soft plastics rigged weedless.
They are both time-saving and deadly in their effectiveness. Rock bars can often be easily accessible to land-based anglers and when fish are holding along your chosen rocky stretch some quality angling can be had without needing a boat.
There is zero need to complicate your retrieval with most of your angling, and when targeting mangrove jack you can limit it to two types – the double hop and the slow roll.
The double hop is as simple as casting your plastic up current, allowing it to sink and when it makes contact with the bottom all you need do is a ‘hop hop’ movement generated by two sharp stabs upward with your rod. Naturally you will need to wind as you do this to retrieve the slack line and keep direct contact with your lure. It is simple and it works. When targeting jacks along the drop-offs this is all you need, but if you do feel the desire to vary it up you can certainly play around with it a little.
The slow roll is again as simple as it gets and works amazingly well for jacks. Along rock bars all you are looking to imitate is a baitfish or prawn swimming back with the current and tidal movement. It is realistic and jacks on the hunt will slam this offering as it comes past. You can vary your speed a little but rest assured that if a jack wants it, he will nail it.
If you are the sporting type of angler you will need to set yourself up with at least two outfits for chasing jacks.
The terrain you are fishing will always determine how sporting you may like to be. Along the drop-offs where the riverbanks are often a mix of mud and scattered timber, I will often use a light spinning combo of 10lb braid and 14lb leader. This handles the vast majority of fish with ease and you will remain in control of your fish. Along the rock bars, however, this is vastly different and I choose to fish 30lb braid and 40lb leader – and there have been times when I have been properly wasted by big jacks. Given that they are sitting directly on or behind rock, they only have to hit and run hard and you are busted within a second. Blink and you won’t even feel it happen. Sure, there are times where you can get lucky fishing lighter, but my view these days is that in hard-fished areas you work hard for your fish so you do not want to blow opportunities. Always aim to fish smart according to the terrain you are fishing.
Seek and Find
As you put the pieces of the jack puzzle together considering tides, lures, gear selection and the terrain they prefer, you will still need to allow yourself time for ‘searching’. On certain outings it may pay to spend considerable time ‘sounding’ and probing the edge drop-offs while examining the bottom on your sounder readings. Many discoveries can be made as structure reveals itself, along with areas that may hold vast amounts of bait. Rock bars and bottoms will also be discovered and even areas that may only be 50m or so of broken up shale-type reef are well worth fishing as tides become favourable. The homework is always necessary for more frequent success and will ultimately lead you to a heavily bent rod as you grunt to gain the upper hand.