Shark warning for Perth beaches

A shark warning has been renewed for Perth beaches after unusually high numbers of bronze whalers were detected in the past week.

The Department of Fisheries says the bronze whaler sharks were detected at Garden Island, Warnbro Sound and Rottnest Island, while a great white was spotted at Scarborough beach.

The warning is an update on an alert issued in August and renewed earlier this month after white pointers were tagged in the Mewstone and Straggler Reefs area over a two-week period.

The change in shark activity may be due to a change in environmental conditions, with an unusual abundance of Australian salmon also noted off the Perth coast.