Every long river has a last mile, and on the Blackwood the last mile is where the rulebook changes. Western Australia's longest south-west river comes down out of the jarrah and the farm country and meets the coast in a broad, brackish estuary, and the state's fisheries authority draws its coastal South West fishing region straight across the mouth.
This short reach is the one part of the Blackwood that falls inside that coastal region. The hundreds of kilometres of river upstream do not. For an angler that matters in a plain way: the coastal rules on species, size, bag and season are not the inland ones, and any advice you read for the river above stops here.
Be clear about what this page can and cannot do. There is no fish record for this reach, no gauge, and no reviewed angling coverage for the Blackwood yet, so it will not tell you where the fish are. It is estuary water, tidal and brackish, and it does not fish like the river above it. Treat the mouth as coastal water, where tide, bar and wind decide the day, and read the current Western Australian rules for the coastal South West before you fish it.
Water and habitat
The short mapped outlet reach where the Blackwood meets the coast and DPIRD's coastal South West reporting area. The mapped segment has three vertices inside the South West polygon and one on the coastal boundary, which is why it is treated separately: the boundary cuts across the mouth, and the reach does not contain the long inland river upstream. It is estuary water, tidal and brackish, and it does not fish like the river above it.
Access and safety
Do not infer access from the mapped river line. Confirm land tenure, launching and any local closure before you go, and treat the mouth as coastal water: tide, bar and wind decide the day.
Regulations
Check the current Western Australian recreational fishing rules for the species, method and date, and confirm whether any local closure or protected area applies at the mouth. The South West region boundary is a reporting geography, not the source that decides the rule; the rules themselves live in the current Western Australian guide, and they differ between the coastal region this reach sits in and the inland river upstream.