Flatties are widely distributed throughout the harbour, from the uppermost reaches all the way down to the heads. Around the heads the smaller sand flathead dominate with the occasional dusky flathead making an appearance. Upstream, the dusky flathead reigns supreme. These fish can grow to impressive sizes , up to one meter , and are surprisingly comfortable in as little as one foot of water.
When it comes to gear, a single-handed spinning or light baitcasting rod with four or six kilogram line will comfortably handle most flathead luring. However, it’s important to use a stronger trace of about ten kilograms to avoid losing fish through bite-offs. While their teeth aren’t particularly sharp they do have a habit of thrashing their head from side to side which can rasp and weaken your line. For bait fishing I would go a bit heavier as there is a real chance of hooking a big jewfish or kingfish on the larger live baits aimed at big flatties.
Timing is everything. The prime windows are the two hours before low tide and the first hour after the tide begins to come back in. Early mornings and late afternoons make these windows even better.
Flathead tend to congregate around channel edges, rock bars, weed banks, and sand or mud bank drop-offs. Any spot where water channels off mangrove stands or flats during a falling tide is definitely worth a cast. Boat moorings in the harbours bays are also worth a look.
They are caught all year round but they can get a bit sluggish in winter especially on lures. If you are targeting trophy fish (remembering the 70cm slot limit) then autumn is by far the best season in the harbour.
Lure fishing
Flathead spend most of their lives buried up to their eyes in sand or mud, rendering them virtually invisible to their prey. Combine this camouflage with a cavernous, needle-lined mouth and lightning-fast reflexes, and you have one of the ultimate aquatic predators. This natural behaviour makes them particularly vulnerable to lure fishing.
They often get a bad rap as poor sport fish, a reputation largely justified when using traditional bait fishing methods. But this perception quickly disappears when flathead are targeted with lures. The skill, thrill, and anticipation involved in hunting flathead on lures rival that of any other predatory species—including the tropical glamour fish. Although the fight from a lure-caught flathead isn’t quite as fierce as northern mangrove species, it is a significant improvement over flathead caught on bait. In the clearer waters of the upper reaches of Middle Harbour and Lane Cove River, there’s often the added excitement of visually seeing your fish strike.
Some of the best spots to lure fish for flathead in the harbour include the shallows of Rose Bay, the upper reaches of Middle Harbour, the entire length of Lane Cove River, Iron Cove, and the Parramatta River upstream from Gladesville Bridge. The yacht moorings in sheltered bays—particularly Balmoral and North Harbour—and spots like Grotto Point and washaway beach also hold good numbers. The key is to keep moving until you find them.
Diving minnows can be particularly effective for trolling, but you’ll need a broad range to cover various depths. While trolling can be an effective way of covering a lot of ground—especially over featureless sand or mud banks at high tide and along channels at low tide—the real fun lies in casting around shallow sand banks and weed beds.
The three main lure types I rely on when chasing flathead are stick baits, soft plastic/jig head combos, and diving minnows. Stick baits excel for shallow water particularly around weed beds thanks to their weed-resistant design —hooks lie flush with the lure, allowing you to fish right through thick cover. The ‘Slug-go’ is a perfect example. For casting deeper drop-offs and channels, soft plastic jig head combos are my go-to. These can be bounced along the bottom regardless of depth, keeping the lure in the strike zone longer. For trolling, lures that maintain a consistent depth are essential so I’ve will always have a few bibbed minnows of various diving depth capabilities on board.
Flathead are opportunistic feeders and will strike almost anything that swims past their face, so presenting the lure close to the fish is critical. Because you’ll be fishing in waters from one to fifty feet deep, your lure choice must consider depth capability. Focus on suitable holes and channels and fan your casts, landing each cast just a couple of meters apart. Let your lure sink to the bottom, watching your line carefully. A taught line will suddenly go slack with a small bump when the lure hits bottom. At that moment, lift your rod tip sharply in a series of three short, sharp, flicks (your rod should finish at about 45deg ), then quickly reel in while lowering the rod tip back down near the water surface , pointing directly down your line and at your lure. Be sure to pick up the line at the same rate that you are lowering your rod as to avoid any slack . (Slack line will make it hard to detect strikes or see your lure touch-down and increase your risk of tip wraps). Now watch your line closely , looking for the ‘bump’ in your line when your lure hits the bottom again . Repeat this method all the way back to your feet. Flathead often strike soon after the ‘flicks’ while it is sinking back to the bottom. This method keeps the lure hopping along the bottom where flathead lie in wait. Mastering this technique is essential for getting the best from soft plastics, not only for flathead but other bottom species as well.
Bait
Drifting
If you prefer a more passive approach, drifting dead bait can be very productive. The key here is to maintain contact with the bottom, adjusting sinker size to match boat drift speed and current. Whitebait is often the best drift bait, but rigging is critical to prevent it from spinning—either using ganged hooks or nose-hooking with a single tarpon pattern hook.
At Anchor/Spotlock
Live bait remains the gold standard, although the gap is closing quickly thanks to advances in plastic lures and fishing techniques. Bait size should match the target fish size—poddy mullet, yabbies, and small yakkas suit average flathead, while larger mullet or yellowtail work best for the trophy-sized fish. These bigger flathead prefer deep water and mud bottom. I use hooks from 4/0 to 7/0 depending on bait size and make sure your baits are presented right on the bottom
Interestingly, there’s a surprisingly high concentration of large flathead in the shallow upper reaches during colder months when water temperatures drop as low as 11 degrees Celsius. I believe these big ‘lizards’ head upstream to enter a sort of semi-hibernation, becoming almost motionless and lethargic—so much so that you might think they’re sick or near death. This behaviour is unusual but they might have more in common with their terrestrial namesakes than we realize. These big flathead move into the coldest water available, despite warmer areas being accessible. They rarely fight or chase prey aggressively during this period, making them tricky to catch. Under these conditions, big lures might actually have the edge over live bait because they allow you to cover a larger area. The key is to bounce a weighted soft plastic lure right past the flathead’s nose in deeper holes—sometimes down to 30 feet. Work the lures very slowly. Occasionally, they’ll venture into very shallow water, almost fresh, at the system’s uppermost extremities.
In short, flathead fishing in the harbour offers a rewarding blend of challenge and excitement, especially when using lures. Whether you’re casting in shallow weed beds or exploring deeper channels, these cunning predators provide excellent sport for anglers willing to learn their ways. So grab your rod, pick your favourite lure, and get ready for some thrilling flathead action.
In New South Wales, recreational anglers must comply with specific size and bag limits for dusky flathead:
- Slot Limit: Only retain dusky flathead between 36 cm and 70 cm in length. Fish outside this range must be released immediately.
- Daily Bag Limit: Maximum of 5 dusky flathead per person per day.
- Possession Limit: You may have up to 10 dusky flathead in your possession (e.g., stored in a freezer), even though you can catch only 5 per day.
