Alex's Fishing Column 26 December 2019
Unbelievably, Darwin’s four brand-new artificial reefs are already producing fish.
I’ve heard reports of big bait balls hanging around the reefs, jewfish and other reef fish being caught and mackerel swimming about above the reefs.
The four reef complexes are comprised of 116 purpose-built artificial reef modules which were deployed early this month: two between North Gutter and Lee Point; one between the Vernon Islands and Cape Hotham; and one in the Dundee Region.
This significant project was overseen by NT Fisheries and, at $8.3m, is a significant component of the Government’s $50 million commitment to developing recreational fishing opportunities in the Territory.
Each one of these huge artificial reefs comprises 29 modules clustered in groups of four or five, with each reef field covering an area of about 2.5 hectares or 25,000 square metres;
end to end, that’s about 1250m long by 20m wide each.
The GPS co-ordinates for the new reefs are:
Lee Point Wide
12 10 083
130 47 033
Adelaide River Mouth
These reefs are destined to provide some amazing fishing but, even though fish are already being caught, don’t expect too much straight away.
NT Fisheries will monitor the development of the reefs over the coming years with an estimated time of around 3 years for the reefs to become fully-established productive habitats, and with a lifespan of more than 100 years.
To assist fishers, NT Fisheries has developed a Code of Conduct for fishing around artificial reefs and FADs:
• Respect other users at all times.
• Courtesy should be given to fishers who are already using the reefs.
• Users should accommodate new arrivals where possible.
• Take only what you need for a feed.
• When you have caught a feed of reef fish, consider changing fishing methods or locations to target pelagic species which are less susceptible to barotrauma.
• FADS and additional vertical relief of reefs will attract pelagic species which are more suitable for targets of catch-and-release fishing.
• Due to the effects of barotrauma, please do not target reef fish species for catch-and-release fishing in waters greater than 10m deep (Note: the 4 new artificial reefs are all in waters greater than 10m depth).
• Always motor slowly when approaching or changing locations to reduce disturbance of other boats.
Fishers should also be aware that there may be spearfishers (who are also covered by the Code of Conduct) in the vicinity of the artificial reefs. The Code also states that:
• Spearfishers should be aware of other artificial reef users.
• Spearfishers may not have possession of a loaded speargun within 150m of another person who is not part of their fishing group and should not enter the water if they are within this distance of other boats at an artificial reef.
The design and construction of the new artificial reefs should not only enhance fishing opportunities but also address ecosystem objectives and suit the environment they are placed in.
They take into consideration water depth, currents, the sea bed and the preferred habitat of particular marine species.
I understand the new reefs incorporate the best features of a natural reef but with enhanced qualities for maximum effect, including internal caves, cryptic habitat, vertical relief and a shape that promotes upwelling of water flow.
They were fabricated locally by Shorecast NT using nearly 3000 tonnes – 180 truckloads – of concrete.
So that takes care of the sea floor adjacent to Darwin and Dundee in terms of purpose-built fish attractions.
However, there are also a bunch of FADs (fish aggregating devices) working to attract surface-feeding fish; ie pelagic species like mackerel, tuna, queenfish, trevallies and billfish.
Originally, there were four but NSW Fisheries has kindly donated another four to the NT that were not been used.
These four new FADs are due to be placed at locations offshore at the end of the wet season.
With all these reefs and devices sprinkled around the place from Cape Hotham to Dundee, you’d have to say it’s a very merry Christmas from NT Fisheries.
The tides are fairly big over the Christmas-New Year break, but are ideal for a barra fish in both Darwin and Bynoe Harbours.
Weather permitting, there’s not that much movement that the offshore scene won’t produce some nice reef fish and pelagics.
Sometimes around Christmas, you get a window of glassed-out seas, and that’s a great opportunity to head out for a mackerel or even a billfish.
Have a wonderful Christmas and please be safe on the water.
The reef modules are all lined up placed on the bottom one by one.
This is the design of each of the four new artificial reef complexes on the sea floor.
The sounder clearly depicts one of the reef pyramids with baitfish nearby.