The blue swimmer crab (Portunus armatus) is found along the entire coastline of WA and in a wide range of inshore and continental shelf areas, from the inter-tidal zone to waters at least 50m deep.
But the greater part of the stock (both commercial and recreational) is concentrated in the coastal embayments between Geographe Bay (in the south) and Port Hedland (in the north).
The commercial blue swimmer crab fisheries in the West Coast Bioregion are the Cockburn Sound (Crab) Managed Fishery, the Warnbro Sound (Crab) Managed Fishery, Area 1 (the Swan-Canning Estuary) and Area 2 (the Peel-Harvey Estuary) of the West Coast Estuarine Managed Fishery. Area 1 (Comet Bay) and Area 2 (Mandurah to Bunbury) of the Mandurah to Bunbury Developing Crab Fishery make up the other paerts of the commercial fishery.
Originally, commercial crab fishers in WA used set (gill) nets or drop nets, but most have now converted to purpose-designed crab traps.
Blue swimmer crabs are also retained as by-product by trawlers operating in Comet Bay (Zone D of the South West Trawl Managed Fishery), and occasionally by trawlers operating in the waters from Fremantle to Cape Naturaliste (Zone B of the South West Trawl Managed Fishery)
Commercial access to blue swimmer crab stocks in WA is governed by a series of separate management arrangements provided for under the existing Fish Resources Management Act 1994.
Fishers are managed with input controls that include limiting boat and trap numbers in addition to controlling by-catch species, size limits, gear specifications and seasonal and daily time restrictions.
Blue swimmer crabs become sexually mature when their carapace width is a little below 100mm. By only catching crabs that meet or are bigger than the legal size limit of 127–130mm carapace width, fishers help ensure there is adequate breeding stock left in the water and they protect the sustainability of the fishery.
The West Coast Estuarine Managed Fishery Management Plan came into effect in July 2014 and this plan incorporated Hardy Inlet and its single fisher into the managed fishery.
During 2012/13, approximately 31 people were employed as skippers and crew on vessels targeting blue swimmer crabs in the West Coast Bioregion.
Blue swimmer crabs also provide a highly popular recreational fishery, particularly in the Swan River, Cockburn Sound, Warnbro Sound, the Peel-Harvey Estuary and the Geographe Bay region, where they dominate the inshore recreational catch.