The mangrove Jack is a fierce and aggressive lutjanid species that is prolific right around the northern parts of Australia.
As the sport fishing scene has continued to develop in this country, fishos have developed a taste for hard pulling, aggressive quarry. Jacks feature heavily on most creek and driver fishers hit list.
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They are reasonably prolific in wild places and modern tackle has helped to bring a coolness factor to these fish.
Mangrove Jack are generally a successful and desirable species to have around, whether targeted or as bycatch.
Larger models have also begun to sneak slightly further southward in their range, encroaching on more urban areas around SE Queensland and northern NSW.
Their tough and aggressive nature suits areas with heavy structure which is prolific around more urbanised waterways filled with rock walls, boats, marinas and all sorts of submerged infrastructure.
Pound for pound
A resident jack simply dominates with ferocity and is often the first fish to strike lures. A well presented soft plastic or hard body will get nailed with a perfectly placed cast amongst the structure. Think fallen trees, big underwater logs and weirdly, the clearer the water the better!
A little snag in a pocket of water might produce not one, but multiple fish. Mangrove jacks are often the eager first feeder, followed with anywhere from double to triple hookups. Their turn of speed and electric first run are well known to anglers and unsuspecting anglers can be left lureless in an instant.
There are always the fierce debates and countless squabbles amongst fishers about which species fights hardest pound for pound.
Most will agree that for an initial burst of speed and energy, few can match jacks except perhaps their large cousins in PNG and parts of SE Asia.
The Papuan black bass and spot tailed bass growing larger in those systems.
Anyone who has held a jack captive in a tank and then fed it will understand. Anything tasty, slow or hasty will have a tough time matching it with these terrors.
Much larger fish will often shy away in the corner when it’s feeding time for Mr Jack. Little prawns and baitfish be aware.
Feeding the beast
Sneaking in on the rising tide, over sandbars in less than a metre of water is a great way to start fishing.
Activity heightened by the spring tides bringing clean water into tiny creeks makes a thrilling way to fish for jacks.
Through the entrance of coastal creeks, surrounded by mangroves, the tides brings a fresh breath on each rise.
With sticks, snag piles and trees as structure and super clean water on the flood tide, look for holes and deeper pockets within the run in.
There are often packs of aggressive Jacks eagerly waiting for a feed coming through on the flood. Big tides on and around the full and new moon increase chances. The greater movement of water in and out, the greater the feeding… it’s on!
A dropping tide in these smaller systems can work equally well as tiny drains and escaping water flush the bait back out of the flooded mangroves.
Getting locked into these systems is sometimes intentional; taking extra water, food, and ice for the fish (beer) is the smart option.
As water drops out and funnels back into the blue, search for snake drains, flats with old trees or small holes next to the mangroves with current flowing into them.
Jacks often line up hiding out of the current behind snag piles waiting for the feed to come to them.
Shallow intersections are always effective with tight mangrove edges.
The fish hide amongst the mangrove roots and will chase a lure a long way out when in a mood. Before the final flow and stop of tide, it’s great to perch the vessel up under a tree with a deep body of water.
Roll soft plastics through the hole, hoping to come across some deeper structure or a sunken tree making a perfect hideout for the jacks.
As the tide stops generally the bite stops.
And it’s time for a well earned beer. Switching to either fresh dead bait or live bait during this lull in activity can still account for jacks as they slowly swim a beat in the thinning water. But generally for them to be hitting lures, a little current is mandatory.
Tackle tactics
Think smaller to medium setups, light bait caster and threadlines with 30-40lb leader, in preparation for the aggressive attack. Casting accuracy and range are the most important factors due to the tight cover these fish live amongst.
A large creek or river jack will be in the range of 50cm and these fish take some stopping in tight cover.
Jacks as many will know have a split life cycle, with many of the larger specimens leaving the creeks and river systems for a life on the outside.
They can grow upwards of 80cm out on the shoals, caves, wrecks and reefs wide of the shallow bays and waterways they grew up in.
Proper tackle is needed to catch these large specimens but they are usually bycatch when chasing other reefs species out wide.
A favourite coloured small vibe, paddle tail or a deep dive suspending lure will all work. You could fill 10 tackle boxes and still not have all bases covered for these fish.
They can be fickle, fussy and ferocious all in the same day.
They can also be smart and a change in offering might be needed once the first is declined or refused.
Always be prepared with a second setup handy for those chaotic moments when jack attacks can cause mayhem.
When tangled into sticks, logs and mangroves you can always leave the tangle and get the second rod into the bite zone.
Reliving a pack attack
Witnessing many different bites throughout month long charters, there have been highlights and core memories locked.
Diving deep into a coastal creek system in Cape York, heading up over shallow rock bars and sand spits we came across a four-way intersection that looked and smelled fishy.
As the tide dropped, ensconced on one of the corners, flicking lures in all directions, to our delight it was a jack session for the ages. Each corner and wedge the fish were biting, surface lures, diving minnows, plastic frogs, suspending jerkbaits, you name it we threw it.
The fishing was wild! We lost count of the number of jacks, and the colours were incredible, white stripes, black stripes, deep red, light red.
It’s as if a large congregation had been found and a return to this location is going to be a special moment.
Let’s hope they bite like that again. Any fisho who has experienced a true jack pack attack lives for the next encounter.
Jacks on the plate
Besides making such great quarry for sport fishers, Mangrove Jack are also firsts rate on the plate.
Found right throughout the Australian region into the Solomons, PNG, Indonesia, Malaysia, Sri Lanka and a host of nearby countries, plenty of people know their virtues as table fair.
With a diet of mainly fish, small crustaceans and molluscs, jacks have a very delicate flesh and a lovely oily under skin, making them versatile for baking, steaming and most other forms of cooking.
Steamed inside a pit of sand atop a bed of scented leaves and covered over with a wet hessian sack is a personal favourite.
It definitely helps to have them bled immediately and gutted quickly if possible to retain the best flesh quality.
At times they get a large fat pouch in the stomach which can literally be used like tallow to fry the meat.
One of the greatest virtues of the humble Mangrove Jack is the shear diversity of environments and different niche they fill. Almost anyone can target them, given the propensity to hit both lures and eat a range of fresh or live baits.
Their dominate nature makes them quite easy to predict where to catch and they taste great on the plate. They really are the Crakka-Jack of fish!
