Blue swimmer crab is one of the best tucker species going in Aussie estuaries and bays. They are hard-fighting for a crab, great on the chew, and dead popular because you can catch them from a boat, jetty or even while wading shallow flats.
In Australia they turn up through sheltered bays, estuaries, tidal rivers and shallow coastal sand or mud flats. They like clean, moving water and are common around seagrass, channels, drop-offs and sandy edges rather than rough offshore ground. Most are found in fairly shallow water, from ankle-deep flats out to deeper bay channels.
Blue swimmers are scavengers and hunters, feeding on small fish, prawns, shellfish, worms and whatever fresh bait they can rip apart. They move around with the tide, patrolling bottom country and using their claws to grab or tear food. They are usually most active when water movement brings food to them.
Tide timing matters a lot — the run-in and run-out both get them moving, especially around channel edges and flats where food is pushed along. Low light can help, with dawn, dusk and even night sessions often producing better than bright middle-of-the-day sun in clear shallow water. Light to moderate wind is usually handy because it stirs the water and keeps them active, but strong wind can make crabbing messy and can dirty the water too much in some systems. Small to moderate swell can help in protected coastal areas by adding movement, but big swell generally slows things down or makes it hard to fish crab gear effectively.
Drop nets, dillies and crab pots baited with fish frames, mullet, salmon heads or other oily fresh bait are the standard play. In shallow bays, set gear along channel edges, seagrass margins or muddy-sand flats and give the bait enough scent to work. Good rope, labelled floats and a simple scoop net make life easier when they come up hot at the surface.
Blue swimmer crabs can swim properly through the water using their back legs, which are shaped like little paddles.