A SHARK warning has been issued for around Garden Island and Warnbro Sound.
The warning followed high numbers of detections of bronze whaler sharks on the Shark Monitoring Network in the past week.
A Department of Fisheries spokesman warned the frequency or duration of the recent reported sightings and detections may increase the likelihood of encountering a shark in Perth metropolitan waters.
The latest update comes after a warning was issued on August 28 and re-issued on September 4 when six white sharks were caught, tagged and released off-shore in the Mewstone and Straggler reefs area by Fisheries researchers in a two-week period.
It is not uncommon for sharks to be present off the coast throughout the year, but the recent number of detections and sightings has been unusual.
The change in activity may be due to a change in environmental conditions – with an unusual abundance of Australian salmon also being noted off the Perth coast.
What to do:
Obey beach closures advised by Local Government Rangers or Surf Life Saving WA.
Take extra caution along the Perth coast, including offshore islands; by swimming at patrolled beaches, not surfing or diving close to the areas of main concern, keeping away from large schools of fish and remaining cautious in metropolitan waters.
If you see a shark, report it to Water Police on 9442 8600.