Reading the weed – Dan Kaggelis – Feb 2015

On face value, chasing barramundi in freshwater impoundments can seem relatively straightforward and somewhat easy. Tens of thousands of barramundi stocked in a non-tidal effected, land-locked waterway can almost be compared to fishing in a very large barrel when compared to chasing barramundi in the wild.

Whilst this may be the theoretical perception of impoundment barramundi fishing, the true reality is vastly different, as many impoundment barramundi anglers will attest to. Impoundments are far from ‘barrels of water’ and are in fact complex ecosystems which at times can be even harder to fish successfully than wild saltwater estuarine environments. It is often this ‘barrel of water’ mentality which leads to the demise of freshwater impoundment barramundi success, as impoundments, like all fishing habitats, need to be thought out and unravelled by anglers to find success. In fact, impoundments can often be much trickier to crack than saltwater wild environments as the absence of trigger feeding variables, such as tidal changes and flows, can make it difficult to develop a plan of attack. To compensate for this, it is vital that impoundment anglers look to other variables within impoundments for clues to unravelling the fishes’ feeding pattern and one of the best variables to focus on to help with this are weed beds.

Weed beds are one of the most dominant structures in the majority of freshwater barramundi impoundments and being able to understand and read how these structures influence the behaviour of barramundi is a big step towards fishing success. Typically made up of the noxious aquatic plant, mimosa, or in some cases lilies, these plant ridden structures play a vital role in the food chain within the impoundment ecosystem, as they provide both food and cover for small shrimps and bony bream right through to the mighty metre-plus barramundi.  It is for this very reason that weed beds are such a hot spot for anglers to target as the presence of bait will always mean that a predatory fish is not too far away. Once again though, there is a lot more to it than just finding a big patch of weed and starting to cast and the following information will provide some insight into not only locating the best weed to fish but also how to fish it.

Locating Weed beds
One of the first factors to consider when targeting weed beds is to understand where the best beds are likely to be found. Weed beds tend to thrive along the edges of impoundments, however, not all weed beds are the same and this is deictated by the depth and topography of the impoundment. Weed beds require relatively shallow water, so once the water becomes too deep sunlight required for weed growth cannot penetrate the water and therefore the weed cannot grow. Therefore, some weed beds will develop close to the bank, but due to steep drop-offs in water depth will quickly end, whilst others will continue to expand outwards and often beneath the surface due to a gradual decrease in water depth. I tend to think of weed beds a lot like refrigerators. Small fridges with a small volume can still hold food, however, a large fridge with plenty of depth can hold lots more and this is very much the case with weed beds. Those weed beds which drop off into deep water can still hold both bait and fish but lack the volume and depth to attract big numbers, whilst other beds which are more expansive due to the gradual decline in water depth will have much greater volume to hold more numbers of both fish and bait. Therefore, one of the first signs to look for when choosing a weed bed to fish is whether it has the ability to hold big numbers of fish, as this will automatically increase your chances of running your lure across larger numbers of barramundi.
To help with this look for obvious visible signs. Often smaller volume weed beds are highly visible to the naked eye and are right on top of the water and end where you can see the surface weed finishes. Larger volume beds are also visible to the naked eye, but instead of just ending where the surface weed stops continue underwater for sometimes up to twenty or thirty metres. This submersed weed is often encountered in large clumps or patches and this is the best type of weed to be fishing for a number of reasons. First barramundi don’t tend to reside right up in the tightly knit weed but prefer to move into it from deeper water when looking for a feed. Therefore, these more isolated patches and clumps of weed often just off big weed beds are perfect places for barramundi to reside as they provide ease of access to the fridge when they get hungry.
When trying to locate these weed beds, the best place to start is around the dominant points of the impoundments. These jutting out headlands are perfect for harbouring these large volume weed beds as they are quite shallow and drop off very slowly into deep water making for some very large volume weed bed formations. It is certainly not a secret that fishing dominant points in dams for big barramundi is a good strategy and this is the reason why, as the large weed beds which reside on them are perfect for holding large concentrations of bait which in turn attract big numbers of fish.

Fishing Weed Beds
Once you have located your desired weed bed, it is important to take a delicate approach to how you fish it. Driving in at full pace can disturb an entire area very easily, so stealth is important. It is vital that you quickly determine where the submerged weed bed begins to thin out and end, as this is where you should begin fishing your lures straight up. This is where having a side imaging sounder comes in very handy as this will give you a high quality read on where the weed patches begin and how gradual the water shallows and this will determine the thickness of the weed bed. Once you have established where the patches begin, quietly anchor up casting distance from this point and begin working your lures. Some anglers prefer to spot lock using an electric motor, however, this can still create a disturbance and underwater noise, so an stealthily dropped anchor or “plonk” (lead weight) is a better option. Once you have peppered the area for half an hour and you haven’t found any fish, up anchor and begin moving closer into the weed bed and continue the same process. This will allow for a comprehensive stage by stage fish of a weed bed from the deepest, patchiest areas right up to the surface edge of the weed. This caters for targeting those fish residing off the weed beds in the patches and those actively feeding right up in the denser weed areas. Some days you will find the fish right on the edges and others out in the deeper water, but once you find them you are well and truly on target to cracking the code. 

Lure Selection
Lure fishing weed beds can be an extremely frustrating process for the simple reason that weed and trebles just don’t mix. Fishing your lure too deep will soon see it completely inhaled but a green mass which can feel like a bag of cement on the end of your rod. This is where lure selection is vital, as best results will come from a lure which swims as slowly as possible just above the weed but not to close that it will get snagged up. This can be increasingly difficult when weed beds go from extremely shallow to deep. Anglers can compensate for this by holding the rod tip high and winding at speed during the shallower spots which will keep a sinking lure out of the weed. The only disadvantage here is that you tend to fish a little fast which can sometimes put the fish off. The better option is to have a range of lures which will swim at different depths to suit the desired conditions. Suspending hard bodies are perfect in this situation as you can fish them down to a desired depth, especially when the depth variance between the shallow and deep areas of the weed bed is a couple of metres.  When fishing soft plastics, you can always opt for a weedless presentation, but be prepared for plenty of hits and spat lures as barramundi are masters at avoiding hooks. The better option is to adjust your weights to match the conditions. This means filing down internally weighted jig heads on popular impoundment soft plastics like Slick Rigs so they are more buoyant and lighter. This is easy to do and involves removing the internal weighted jig head and cutting back the weight until you achieve the desired result. Pre-swimming them before hitting the dam is a top idea as this will give you a good idea as where the lures will perform their best.

Unlike other impoundment structures like timber, weed beds are far from static and can change dramatically in a very short time. Large amounts of rain fall can see dam levels rise and see weed beds completely submerge to the point where large volumes of water reside behind the surface beds of weed. Barramundi will reside in these areas and unless you are prepared to fish over a huge bed of weed they are almost impossible to target. Alternatively, over dry spells, weed bed areas can become very shallow very quickly and over the drier summer months weed bed areas can change dramatically in just a few weeks. This is what makes impoundment angling so refreshing, as changes in water levels can dramatically affect every facet of the fishing. This is why it is integral to be able to read the weed to get the best result as this will allow you to be flexible with your fishing.