Mangrove Jack are undoubtedly one of north Australia’s premier sport fish. They are the violent ruffians and rascals of our estuaries and many battles fought with these brutes quickly swing in favour of the fish. Hard, fast, powerful short runs give this fish a distinct advantage when the battle is fought in the vicinity of mangroves or man made structure. That first burst of adrenalin from the fish usually determines who wins the often quick, brutal battle.
From 2003-2007 I spent considerable time chartering in Far North Queensland and can honestly say that I never had a disappointed customer when the jacks were out to play, in fact they were 2nd only to the barramundi as the most requested target estuary species. 1-2 kilo specimens are prolific around the tidal reaches of our northern rivers and estuaries and they are frequently caught right up into the far fresh water reaches whilst targeting other sport species such as Tarpon, Jungle perch and Bass.
Jacks are caught in northern NSW in small respectable numbers but as you travel north along the Qld east coast there density thickens and they extend all the way around to the north west of W.A. Although the numbers are thicker in the most northern estuaries the size in the most southern limits is substantially bigger. The larger fish migrate out of the estuaries during the hottest months usually when they reach the 45cm plus mark and school up in deeper water around structure but to tackle them out of the estuary environment is a totally different story.
Trolling for Mangrove Jack
Although sometimes looked upon as amateurish, trolling is an effective and productive way to introduce inexperienced fishermen to lure fishing and a great way to explore a new area. It is also one of the most effective methods to target these rouges when applied correctly. 20 years ago when I first started experimenting with lures I occasionally trolled up the odd jack and a few other species in the Gold Coast canals and on the Fisherman Island rock walls in the Brisbane river. When I moved to North Queensland to pursue a career in fishing I adopted the same tactics with instant success. Fishing an area with such a large population of jacks enabled me to hone my trolling tactics to the point where I could just about predict how many would be boated. The most important factor when trolling for jacks is to be in the zone. About 30cm off the bottom is what I would call the perfect position in the water column. The occasional puff of sand or bump over a log 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. Bibbed lures are designed to swim at a certain depth however that can vary due to leader and main line diameter and it is also governed by the amount of line you let out. The last few hours of the run out tide and first of the run in tide is the most effective troll time. At high tide jacks will often head into shallow mangrove ridden areas to chase bait fish, at low tide they are forced back into the main channels where I believe they do most of their traveling. When trolling stagger your lures out the back and I suggest you do this for two reasons; the first is to try and cover as much area as possible and the second is to avoid fouling with each other. If you’re spreading different depth lures place the deeper divers in close and the shallower lures further back. When working a new creek take the time to map out your troll path concentrating on the channels, structure and mangrove undercuts. By studying your local water way you can refine a troll path that will constantly have your lures in the zone. The creeks and canals that have worked best for me are those that have an average low tide depth of approximately 2-3 meters. I have trolled for Jacks in depths up to 15 meters with the use of down riggers but with nowhere near as much success.
Once you catch a jack whilst trolling work over the same area a few times because despite having a reputation as being a territorial fish there’s usually a few hanging out together. They tend to hang in the same area for weeks at a time but do move according to the weather, bait availability and water temperature. When trolling back the drag off a little especially if the rod is in the holder because they hit pretty hard! There’s a lot of inertia behind the boat, when the fish hits a trolled lure the boat keeps going, the rod bends a little and something has to give. Don’t be lazy, hold your rod and use your arm as a shock absorber it only takes one hand so you can still sip a tinnie or steer with the other. I have seen rod holders snap and also rods ripped from angler’s hands. A 10lb line main line and 20lb leader attached via a double to the main line will succumb most jacks hooked on the troll as most fish are relatively free from tight heavy structure.
Casting at Structure
This can be brutal! Once you’ve been bricked by a Jack back into the snags you realise how important it is to get the upper hand straight away. For this reason tight drags and main line of 15-20lb and leader of 30 to 40lb is highly recommended.
In the remote areas of Northern Australia where they are at their thickest, pommy cricket scores are sometimes caught in a dream day session. On the Cape of Qld I’ve seen balls of fish fighting for a lure as it’s retrieved from the snaggy haunts they reside in. When choosing an area to lure I always look for thick deep snags, bridges, rock bars, and shady mangrove undercuts that are still submersed at low tide. Run off gutters and creeks with snags at their intersection are also a prime target area.
Once you’ve eyed a likely lair the idea is to pepper the structure as accurately as possible. Don’t sit on a snag and flog it to death, if you don’t get a hit within a half dozen casts move on. If you’re not getting your lure into the thick of it you’re not in far enough. An electric motor to whiz yourself along a snag line or rock wall is a must for any one serious about targeting them however using a mental calculation of the tide, current and wind can work depending on the severity and circumstances of conditions. If all else fails you can anchor back off the snags and work them over. The more area worked usually results in higher numbers hooked, hence anchoring will result in less fish as it is more time consuming.
Jacks are usually responsive to medium/slow erratic deep retrievals, but experimentation is always the key. A good place to start is with a deep diving buoyant lure that will dive down the snag face a little. If you hit the snag just let your lure float up a little and continue retrieving. Suspending lures allow you to stay in the zone giving longer hang time. Sinking lures although effective are much harder to work around structure and more likely to snag.
Tides and Times
As with most species the tide 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. For both trolling and casting at snags the optimum luring time of the tide is about 2 hours either side of the low tide change. No run no fun! Having at least 1 meter of run in the tide for me has produced the most consistent results. Neap tides produce very little when trolling or casting. The 5-3 days leading up to the new moon is from experience the optimum time to target them and 5-2 days leading up to the full moon also produces good numbers. These days I am not able to always fish the optimum tides due to family and work commitments so I make the most of any opportunity.
In the cooler months of Qld around May when that cold snap sets in (15-20 degrees) the water drops suddenly and they almost go off the bite at the click of your fingers. You will still catch them in winter but the bite does slow down considerably and they are much more of an option floating live baits into the snags or targeting them at night on the mangrove flats with live or cut baits. Jacks respond well to sudden rises in the water temp and react badly to sudden drops in temperature just like the barramundi. From May through to the end of August I do not consider them a viable target species for lure tactics. In my home waters of Noosa when the water temperature rises back up to 20- 24 degrees they go in search of food just like a bear coming out of hibernation. The warmer the water, the more energetic, curious and troublesome the fish become.
Low light hours being either first or last light, heavily clouded days or heavily shaded areas are the best times or places to target Jacks on surface lures. If it’s too bright they will be easily spooked or they will be feeding in deeper water in relative safety. You will still catch them but not to the same extent. I have proven to myself over time that Jacks do not like to rise from deep water to attack a lure however there have been odd exceptions. Water clarity also plays its part in success, clear shaded water usually around the slower/neap tides seem to work best. In the estuarine reaches the water is usually clearer around the neap tides because there is less run to stir it up. Wind direction, rain and rain run off are also culprits in determining the water clarity but it’s nearly impossible to get everything perfect. My best surface sessions have always been in relative calm, clean water. There are many types of surface lures available that work well and different ways to work them. Poppers between 5 and 10 centimetres will work best when presented with a little finesse. I don’t think colour seems to matter so much when chasing them on the surface and using a heavy leader for me has been no disadvantage because I believe the fish are concentrating on the main body dispersion of the lure rather than what is dragging it along. The main retrieval patterns that I use are simple small blooping strokes back to the boat and walking the dog. If there is more than one angler fishing use a variety of surface lures until you find which are working best. I’ve had fickle days when only one type of lure will catch fish. Practice and variation is the key to success especially on those hard days, sooner or later something will start to work and when it does stick with it. The small blooping action when popping is basically made by keeping your rod tip down and twitching the rod towards your feet as you take up slack line. Walking the dog is similar but a rhythm is worked which makes the surface lure swing from side to side. Most surface lures are designed to do one or the other although hybrid poppers are becoming more popular. Jacks don’t like a fast retrieve skipped back to the boat, that’s more a pelagic technique but a quick squirt and pause attack has worked a few times. The more ground you cover the more Jacks you are likely to catch. I work the likely looking haunts as accurately as possible trying to get right into the structure and as far up into the mangroves I can without committing suicide. Most of the hits happen within the first few bloops but I have had them hit at the boat in open shallow water.
Timing of the tides is the most critical factor to ensure a successful surface fishing trip. Ideally you need to time it so that you have what I consider the magical depth of .6-1.2 meters of water covering the area you wish to fish coinciding with the lower light situations mentioned. The longer the water remains at the magic height the better. On the bigger spring tides Jacks seem to go right into the inaccessible mangroves or structure in chase of a feed hence fishing the neap tides which coincides with the first and third quarter of the moon phase has been a standout. This is a time when other methods of targeting them by trolling or snag bashing can be less productive. Jacks are just about always there for the taking.
With any style of fishing, lure selection is a personal preference and there are so many proven types. More important than any other factor is having sharp quality hooks. Using rusty and weak hooks will dramatically decrease your hook up rate. I’ve seen Jacks caught on every colour of the rainbow but I usually start off with gold or a natural colour in clearer water. Pink and green seem to stand out in discoloured water. On some days one particular colour will catch every fish and on others they’ll hit everything you throw at them.
Remember what works today might not be in season tomorrow, however, it’s always a good place to start.