Mud crabs are often ranked at the very top of culinary lists. Catching a feed of muddies is a great way to live like royalty and feel proud of yourself. With mud crabs selling for about $50 each or more, this also saves your hip pocket. There’s a great deal of fun watching your crab pot rise into view as you pull it in up through the water and spy two or more bucks captured in there.

Around the top of Australia, muddies are targeted by fishers who use crab pots or lift dillies baited with either fish frames or other oily morsels.

A lot of theories abound about the best times to catch mud crabs. Generally, the warmer months produce the top results in the southern parts of the crab’s distribution. It is quite the opposite further north in the Top End, where the preference is the period from May to October, outside of the wet season’s monsoonal rains.

When/where
Two species are found in Australian waters: green mud crab (Scylla serrata) and orange mud crab (Scylla olivacea) aka brown mud crab; another two species exist overseas. The orange/brown/red mud crab is located in Western Australia and some parts of the Northern Territory. Mud crabs inhabit tropical to warm temperate waters from New South Wales northwards along the Queensland coast, throughout the coastlines of the Gulf and Northern Territory and then down to Shark Bay to the Exmouth region in Western Australia.

Mud crabs generally live in burrows and exit them to forage for food. Their prime feeding areas are out of the main tidal flow around the mouth of small drains and creeks or deeper holes in the creeks.

Female crabs (jennies) release pheromones to attract males; then once fertilised the female heads offshore to release her eggs in batches. When they hatch, the young transform through various stages of mini-moulting while they drift towards shore. Eventually, they develop a set of claws and move inshore. It takes about a month for the 20mm wide version to settle in a sheltered area such as an estuarine or mangrove habitat.

Crabs moult as they grow. Each subsequent shell increases in size and while the new shell hardens the crab feeds ravenously to put on weight/flesh to fill out the carapace. During each moulting cycle, a new cuticle forms under the existing shell. As the crab absorbs water, it splits its outgoing shell. The old shell splits along squiggly suture lines that sometimes can be seen if you look closely at the top of the carapace.

Pot setting
Muddies are commonly found and fished for in mangrove-lined creeks. To target muddies, try to place most pots hard up to the mangrove edges.

And make sure that each pot is sitting flat on the bottom and upright. Obviously, this is critical with top-entry models of pots so that the crabs can access the entrance. Also, the bottom of the pot needs to be sitting flat on the mud otherwise the crabs will crawl underneath and have a chew of the bait without going inside the trap.

It is considered good practice to align the openings of side-entrance traps so that the current (or drain) flows into the pot’s main entrance.

Many crabbers like to set their pots at the mouths of side drains on the falling tide. The theory being that the crabs will be flushed out of the drain and towards your baited trap. Even small drains are ideal for muddies  just leave your pot in water that is deep enough to cover it at low tide outside the drain entrance.

Set your pots, or check and move them often, so that they are not exposed out of the water by a falling tide. Looping the rope and float over a mangrove branch reduces the risk that the ropes may drift across the navigable channel of the narrow creek and become tangled around soon-to-be submerged mangrove roots.

It is also important to make sure that your rope is long enough for the float to remain visible at high tide. Conversely, if the rope too long, shorten it with a knot or cable tie to reduce the chance of tangling.

The are many systems and tactics that work productively for catching crabs. Mud crabs are said to be more active at night. Accordingly, pots set in the target zone overnight will usually produce consistent results.

An alternative strategy is to set your pots during the day and check them every half-hour or so on a rising tide. With this tactic, keep moving your pots further into the side drains as the tide rises on the run in. You may like to refresh your bait regularly too. Fresh oily bait is a sure-fire secret for the best results. Ideally you may consider, depending on the time of the turn of the tide, having part of your crabbing trip coincide with pre-dawn light or just after dusk in the early evening. Make sure you take plenty of DEET-based mossie repellent.

Rain will also cause the crabs to move around. If there is a lot of rain, switch your pots to deeper water in the creek channels as the denser saline water which the crabs seem to prefer, lies in the bottom of the gutters and channels below the muddier fresh water that is on top.

Locations
In areas of high current flow, focus on entrances to creek drains lined with mangroves. Drains just wide enough to fit a small boat into are perfect. Being mindful of the tide stage, try to have your pots as far up the drain as you can, especially when the tide is rising.

Steep muddy banks and undercuts, particularly on the outside of sharp bends where the water is deepest under overhanging mangrove tree species are good too. At low tide, you may even see some of the mud crab holes in the banks and mudflats. When setting your traps, look for water that is about a metre deep on low tide. Importantly, try to avoid locations that appear to be heavily targeted and have lots of boat traffic.

For tropical outings up in the Northern Territory, the Hayes Pots brand has various models to suit the tactic. Hayes Pots are all based on the top-entry volcano-shaped design theory. Crabs climb up the netting and then fall in through the top of the pot.

Use the Hayes Drop Pot float-ring model with the widest opening so that the crabs can readily find the entrance and tumble in quickly. Obviously, the broader collarless gap may let the crabs find their way out when you leave the pots for too long. If a bunch of crabs move in there and eat all the bait, they may start wandering around and find the exit. So, logically the secret to success is to check the pots every half-hour or so. In the Hayes Drop Pot model the bait bag is in the centre and a simple draw-cord shuts and encloses the bait  – it really is an efficient design. This simplifies the sometimes messy job of baiting-up and with the bait in the centre on the bottom of the pot, the crabs basically have to go into the pot to have a chance at the food offering.

If leaving the pots set for a few hours or more, use the Hayes Pots All Nighter model. These ‘collared’ pots are ideal for where you drop the pots and then go fishing for a few hours before coming back on the way home. Barramundi and mud crabs sound a good combination.

When leaving the pots for a long timespan, such as overnight, use either of the All Nighter models. Both the All Nighters have deep collars/sleeves so that the crabs cannot escape. One style relies on the float ring to hold the shape of the submerged pot when it is in the water, therefore no assembly is required. The other model has PVC uprights.

The float ring ‘deluxe’ All Nighter is easily deployed by throwing it from the bank. The floating ring lifts the top up from the bottom when in the water – this ingenious idea also means that there are no side braces to have to put in place. Pretty much the pot self-assembles… how easy is that!

This round, collapsible, stackable mesh pot is straightforward to use. They are swift to assemble, store well and are productive crab catchers. The float ring keeps the walls of the pot up off the bottom. The angled sides seem to enable the mud crabs to walk across and then fall into the pot.

On the Hayes Pots All Nighter model, the PVC pipe sidewall braces keep the walls up during longer sets and in stronger side currents. The collar at the top may mean it takes longer for the crabs to enter the pot – which suits longer duration placements. The collar also makes it harder (if not impossible) for the crabs to exit – which is also suits overnight (or all-day) sets. The PVC uprights stay in place and the base folds in to allow easy stacking. Simply close the bottom of the trap for assembly when out on the water.

The Hayes Pot crab traps are heavy based which means they stay in place and the correct way up when set – and they are less likely to be washed away in the current.

Lesser lightweight pots will often need the addition of up to four snapper sinkers on the bottom. These are expensive so it makes sense to buy the better pot in the first place.

Rules
For on-water activities and fishing, each region can have distinctly different rules. And so it is for catching crustaceans. 

Specifically, the rules can differ greatly for mud crabbing. So you need to check the details before embarking. For example these could include such things as the number of and dimensions of crab pots/nets/traps per person/vessel. Also, note the bag limit of mud crabs per person/boat. There may be restrictions on the styles and dimensions of apparatus used to capture crabs. Float sizes and shapes can come into the equation as well.

These days, all the rules can be found online so take the time to read them.

Pot potpourri
If you have local rules that outlaw certain pot types – for example top entrances are not legal in NSW – here are a few points to consider.

If not built-in and secure, think about a standalone specialist bait bag of the heavy drawstring type that can be secured at both ends to the inside base of the pot/dilly. These bait bags can make baiting up (and disposing of old used bait) easier as well as keeping the bait intact longer, especially when captured crabs start gnawing at it.

Large round, four-entry heavy-duty crab pots are considered a better option than the two side-entry models. Although larger heavier pots with stronger mesh and more entrances and thicker galvanised rings are preferred, you may have to compromise if space or weight is an issue.

If you are using smaller, lighter pots, target spots with lesser currents such as small cul-de-sac pockets and drains. Heavy-duty triangular pots are also available.

Bait
Chicken frames, or even turkey drumsticks/shanks, make an ideal bait for mud crabs. However, the frames of non-predatory or oily fish species like mullet are arguably the best of all.

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