Mangrove Jack, a fierce strong fighting predatory fish that moves out of the estuaries at an adult age to begin breeding and terrorising the offshore reef systems. Much to fishermen’s belief the offshore reefs have an abundance of large mangrove jacks over a vast area of the Australian coastline. It’s not uncommon to see schools of 5,10, 50 plus big jacks roaming the reefs. These fish are often responsible for lighting up the sounder with great shows of quality fish but much to fishermen’s frustration they can’t seem to catch a fish.
Reef Jacks have very unique feeding habits that mean they’re not commonly caught by line fisherman particularly during the day light hours. Even though they move from estuaries to reefs they keep one thing in common and that’s structure. Any reefs or rocks that offer overhangs or caves make the perfect habitat for reef jacks. They will often move around the reef system away from the main structure which gives fisherman a far greater chance of landing a monster jack.
Big reef jacks aren’t hard to catch, but getting them to feed is the biggest challenge. Over the years I’ve found that around the full moon they become very active at night and this is when you need to target them if you want the best chance to catch one. Although we’ve caught them all through the night on full moons, a very large percentage is caught around 2 or 3am in the morning. Now fishing all through the night or 2am in the morning may not be everyone’s cup of tea but if you want the best chance of catching a big reef jack then you really need to do this.
They will take a large range of live and baits and don’t seem fussy when they finally switch on and feed. Although we’ve caught them on paternoster and floating rigs, I do prefer floating style rigs as these fish move around the water column a lot and will happily feed on baits 10-20mtrs off the bottom.
Unfortunately Reef Jacks suffer severely from Barotrauma when being pulled to the surface. This means they can’t be released as survival would be unlikely due to internal ruptures. As tested, jacks are slow growing and fish around 11 to 15kg and 1mtr plus in length can be 50 plus years old. Mangrove jack are very sustainable with a great future a head and as much as I’m an advocate for catch release in the estuaries, be mindful that there’s nothing wrong with keeping one occasionally for consumption.