Alexandrium algal blooms

Since 2019 Alexandrium (an algae) has been detected within the Swan River at elevated levels.  It is known for negatively impacts waterways and fisheries around the globe and is expected to be an annual occurrence within in the Swan River. 

These algae produce Paralytic Shellfish Toxins (PSTs) that can accumulate within mussels and crabs. PSTs poisoning can be fatal to humans;  a meal of 3-4 whole crabs can result in symptoms. 

To reduce your risk of ingesting PSTs: 

  • Do not eat mussels from the Swan River
  • Clean any blue swimmer crabs caught in the Swan River by removing the head, guts, mustard and gills prior to freezing, cooking and eating

Swimming, water-skiing, and boating is OK, but as a rule swimming should be avoided in areas of discoloured water. It is also safe for dogs to swim in the water. The public is advised to pay attention to algal bloom caution and public health warning signs displayed in the Swan Canning Riverpark and to watch out for Alexandrium updates in the media. 

For additional Alexandrium algal bloom information visit the Swan River Trust website.