Shark detections show some bite

A pair of sharks off Middleton Beach have caused a sharp spike in shark detections in 2016, with 109 recorded compared to just five in 2015.

Last year the 109 tagged shark detections were made by the Shark Monitoring network at Ellen Cove, Middleton Beach, eclipsing just five recorded in 2015.

The detections off Ellen Cove were traced to two tagged bronze whaler sharks, which moved through the area repeatedly.

Department of Fisheries Shark Response Unit manager Lisa Clack said an increase in detections is not always an increase in sharks.

“Detections from acoustic tags are transmitted every five minutes while a shark remains within a range of a receiver, so a single shark can cause multiple detections,” she said.

“Therefore the numbers of detections don’t necessarily mean an increase in tagged sharks in the area compared with previous years.

“In the case of the 2016 detections at Ellen Cove, these detections were all from two bronze whaler sharks.”

Middleton Beach was closed by authorities on Thursday with swimmers advised to swim at their own risk after a tagged tiger shark was detected twice at Ellen Cove.

Ms Clack said since January 1 there has been one tiger shark detected four times and one bronze whaler shark has been detected once at Ellen Cove.

In 2016, detections were also up at Frenchman Bay with 35 detections compared to 13 in 2015.

In 2015, 18 shark sightings were recorded across a number of popular beaches including three sightings at Middleton Beach and 13 at Cheyne Beach.

Last year only five shark sightings were recorded at the same beaches.

A total of 63 white sharks have been tagged in WA.

In nearby South Australia, authorities have tagged 166 sharks.