Monday, August 30, 2010
2Dans Fishing – Radio Program 5 – Sunday 5th September 2010
Fishy Fact File – Mangrove Jack Lutjanus argentimaculatus.
This species has a huge range throughout the Indo-Pacific region as well as the Red Sea, and an impressive distribution throughout Australia. The Mangrove Jack is a member of the Lutjanidae Family, this group is known commonly as the sea-perch and pacific snapper family. The various species are categorised by robust body’s strong tails, canine like teeth and aggressive carnivorous feeding behaviour. The mangrove jack is the second most sought after coastal species after the Barramundi for northern based anglers. In addition to the recreational value, there is growing interest in Mangrove Jack stocking into impoundments as well as a number of ventures testing the viability of this species for aquaculture.
These amazingly powerful fish spend their juvenile lives in estuaries, creeks and rivers, migrating offshore as they reach sexual maturity. These fish are the prize to many anglers and for their size and weight there are few fish that fight this hard over short distances. The can be taken on a variety of lures and live baits. The best fishing for them late afternoon/dusk into the night and through till a few hours after dawn. Anglers should fish the heaviest tackle they can hold onto and still be prepared to loose many fish. They taste great on the plate and should be treated with culinary respect.
Distribution and Habitat: In Australia its range includes all northern coastal rivers systems from northern New South Wales (although they are sometimes encountered as far south as Sydney's offshore reefs and coastal lagoons), through Queensland, the Gulf of Carpentaria, the Northern Territory and into Western Australia as far south as the Ashburton River System. They are encountered on reefs up to 100 metres deep right up into brackish and freshwater reaches of tidal rivers.
Size: The unofficial Australian record was caught offshore from Byron Bay and is around 15kg and well over the magic 1 metre mark. Most fish encountered however are between 800grams and 3kg, although any ‘Jack’ over 1kg is a catch worth being super proud of. Very little is know about their reproductive biology, although it is thought they broadcast spawn millions of eggs into the pelagic environment from the estuaries.
Age, growth and sexual maturity: An interesting research paper was recently released on a three year study looking at the ‘Biology, management and genetic stock structure of mangrove jack in Australia’. Five scientists from Fisheries Research and Development Corporation sampled and collated data from around the country to bring out the most comprehensive study of these unique and important fish.
Their research indicated that Mangrove jacks living in the freshwater and estuary environments are juveniles and that sexual maturity is not attained until they migrate offshore. This seems to happen between three and 11 years of age. It is thought that they spawn at sea and the juveniles travel up into the freshwater reaches of coastal streams during the wet season.
Otolith growth records indicate that mangrove jack are long-living fish, with the oldest specimens at least 37 years old and possibly 40 years or more. Growth rates slow down measurably with age. The longest confirmed length of ‘Jack’ was an astounding 120cm, whilst the smallest caught throughout the project was a mere 20mm, taken at the mouth of a northern QLD river during the wet season.
The study showed that the juveniles migrate inshore during the wet season, after being spawned well offshore It was also observed that population density was at its greatest around the mouths of estuaries and decreased moving upstream. The number one habitat location for the mighty mangrove jack was found to be rock walls and bars, followed by submerged timber snags.
Throughout the study (and from other tagging data) fish were tagged and released, results from this showed that juvenile jacks are territorial, 73% of recaptures occurred less than one kilometre their capture and release location. In numerous instances individuals were recaptured in the precise location the were originally tagged in. Interestingly fish that migrated offshore are capable of traveling vast distances with the record holding individual swimming a remarkable 335km along the north Queensland coast.
Essentially all mangrove jacks caught by rec. anglers in estuaries and river systems are juveniles. It is noted that 50% of female jacks reach sexual maturity at 512mm and males at 459mm. This should be noted and considered by anglers as the QLD legal size of 350mm is well below the size at which they become adults and have the first opportunity to spawn and create stock for further generations. In NSW there is no minimum size limit, so anglers need to make there own judgement. This being said authorities feel that the current size limit allows recreational anglers to catch and ‘take’ fish from the estuaries, as the larger fish will have moved offshore. Another interesting fact is that fish from the southern reaches of the distribution grow faster than their northern counterparts, as a result larger fish are sometimes encountered within estuaries in NSW.
For the full document click on the link here; www.dpi.qld.gov.au/fishweb/7096.html
Tackle: Due to the power and aggressive nature of these fish the tackle used to specifically target them needs to be strong and capable of heavy drag settings. Overhead set-ups are generally preferred although the latest quality offerings in thread-lines would definitely stand-up to the challenge. I would recommend nothing less than 30lb braid, and a rod of six to seven foot in length capable of fishing 8-12kg of drag over. Leaders need to be heavy in order to stop the fish in it’s tracks, and I’ve noticed some gun ‘jack’ anglers using a 30cm length of 60-80 lb single strand wire connected to the lure or live-bait hook to survive the inevitable bust-offs that occur when the fish make it back to the snag. It is often said that mangrove jacks hit their prey, lure of live-bait on the way back to their nook or cranny. So you’d better hold on and be ready for action.
Eating qualities: Mangrove Jacks are amazing to eat, the flesh has tasty medallions when cooked properly. Smaller fish can be baked or steamed whole, whilst larger fish are best filleted and then pan-fried or cooked in foil with a selection of herbs. For more nutritional information click on the link; www.australianseafood.com.au/species.php?f=114&v=f
Tackle Happy – New tackle treats from the Fishing Tackle Trade show
Well Dan Burgess and myself were fortunate enough to recently travel up to the Gold Coast or GC as it is affectionately known and attend the Fishing Tackle Trade show. Unfortunately this event is only open to the industry to peruse new products on display and get their orders in for the upcoming season. It is quite an experience for a tackle junkie like myself to be let loose in an exhibition centre big enough for almost every tackle manufacturer and distributor in the country to be represented. New reels, new rods, new lures, new hook and jig head ranges, plus more accessories than you could ever hope to need. There were a number of stand-outs amongst the millions of items on display, and perhaps most notable was the huge range of squid jigs from almost ever tackle house in the world. Daiwa, Shimano, Mega-Bass, Yamashita, Yo-Zuri and on and on, so if you like your squidding stand-by for some amazing new releases – in next weeks show we will have a quick look at the new technology being packed into the not so simple design of the new breed of squid jigs.. Interesting to also have a play with were the new range of Loomis rods, whilst Shimano have released a new series of the infamous Trinidad overhead reels. Daiwa never cease to impress with a new Certate reel sure to be dynamite and a new Steez rod with a 7’10” length for those snapper anglers wanting to get a touch more cast in. On the jigging front Tuff Tackles budget jigging reel and well considered jigging riod will please anglers after a well priced robust fish stopper. I’m also excited by the arrival of Abu’s Dreadnaught series of Jig Rods, I now have two of these (the 30lb and 50lb versions) in my hands for fishing, testing and review – Standby for updates on these. Also a brand new range of threadline rods and reels from Pfleuger which I am keen to get out and test this afternoon on Sydney Snapper, the Patriach rod and reel set-up are quality super light items with modern technology delivering superior strength at a friendly price point. Other items we will review in coming weeks are Hayes Crab pots, the Squidator (new style of squid spike), Mako’s new range of polaroid sunglasses, the Seeker jig heads and a few of the recently released braid lines.
2Dans Fishing – Radio Program 4 – Sunday 29th August 2010
Tackle Happy - How to Keep a Fishing Diary
Keeping a fishing Diary is a process that many anglers neglect, and one that at times I forget to keep up to date, especially on days when the fishing was slow. However if you really want to improve your chances of catching more fish regularly a fishing diary will help you do just that.
The basic diary records the date, the time of day you fished and the locations you fished and the fish you landed, it is also worth noting the moon phase and tides, although an old alt tells me these are the same each year (I have yet to check and see whether this is indeed the truth - anyone confirm or deny this??). If you desire to keep a more complex diary then you can also keep info like prevailing conditions, water temp, water clarity, previous days weather conditions, the bait you caught as well as used, what the air pressure was doing (barometer readings) and so on.
The aim of a fishing diary is to help you get in synch with the natural cycles that happen in the oceans and your local waters. What you will begin to identify is that everything has a natural cycle with the same species of fish turning up at the same locations at the same time of year each year. Water temps will alter this some what, and a falling or rising barometer will affect whether the fish are biting. But for the most part the calendar will help you determine what to fish for and when, so get started all you really need is an exercise book and a pen. If you want to go back over past info, pictures that are dated will help you recall dates and for memorable trips your memory will have a lot of the other info.
Boats and Bits - Evinrude E-Tec
There are many outboards on the market these days, essentially there are two categories of outboard available to the consumer. Old school 2-Stroke technology which has been around for decades. And clean technology outboards which are then divided into 2 separate categories; 4-Stroke Technology and Direct Injection 2-Stroke Technology and the latter is what we are really all about. As the name suggests Clean technology delivers a cleaner more efficient use of fuel and releases far less pollutants into the water and atmosphere.
The benefit of Direct Injection 2-Stroke technology is that in addition to giving you greater fuel economy, lower emissions of pollutants into the water and a quieter ride, they also deliver greater torque and power than the same horsepower 4-Stroke outboards and weigh less too. As a result there really is no other choice.
Envinrude E-Tec lead the direct injection 2-Stroke market today, they are easy to own and operate, require far less servicing than 4-Stroke outboards, and deliver amazing power and torque for their weight and keep up with 4-Stroke outboards when it comes to fuel efficiency and low emissions.
If you haven't been on the water with a boat powered by an E-Tec then you owe it to yourself to experience what they truly deliver.
For a review of the Evinrude E-Tec 150HO check the link below;
or for more information for the manufacturer or to locate a dealer clink on this LINK
Thanks for checking out our blog, and remember to tune into our radio show every Sunday morning across our Fishiy nation, see below for Radio Station details in your local area.
Coffs Harbour - 2CS-FM
Port MacQuarie - 2MC-FM
Wagga Wagga - 2WG-FM
Central Coast - 2GO-FM
Albury - The River-FM
Townsville - 4TO-FM
Cairns - SEA-FM
Gladstone - SEA-FM
Mackay - SEA-FM
Fraser Coast - MIX-FM
Sunshine Coast - MIX-FM
Darling Downs - 4GR-AM
Gold Coast - GOLD-FM
Mt. Gambier 5SE-AM
Hobart - HEART-FM
Albany - 6VA-AM
Kalgoorlie - 6KG-AM
Merridin - 6MD-AM
Narrogin - 6NA-AM
Bridgetown - 6BY-AM
Busselton - 6CI-AM