The Western Australian government has denied it uses scientific tagging data to label sharks as a “serious threat” after a private shark researcher said he was considering withholding information about sharks he had tagged to prevent them getting caught in a cull.



Andrew Fox, who tags great white sharks in South Australia for the Fox Shark Research Foundation, told Guardian Australia on Wednesday he was reconsidering sharing data that would allow the WA Department of Fisheries to track sharks he had tagged after a kill order was issued for a tagged shark in December.

But the department’s executive director of research, Dr Rick Fletcher, told Guardian Australia it was “misinformed” to suggest that scientific tagging data would be used to make culling decisions.

“The government’s serious threat policy is very clear about the circumstances under which an order to take a shark will be issued, including a rigorous assessment process and a number of factors to be considered,” he said. “Claims that detections of tagged sharks will be used as a sole trigger to capture sharks are misinformed.”

The WA Greens MP Lynn MacLaren said Fletcher’s comments contradict an order he gave in December to catch and kill a female great white shark at Warnbro Sound, 55km south of Perth.

“Dr Fletcher has ignored the fact that before Christmas he ordered a hunt-to-kill of a tagged female white shark whose presence was only known about because she had been detected multiple times by Fisheries’ acoustic receiver in Warnbro Sound,” MacLaren said.

“At no point was there any suggestion that any member of the public had even seen the tagged shark, let alone there being any evidence that she was posing a threat to humans.

“It is well-established by Dr Fletcher’s own department that snapper spawn in Cockburn and Warnbro sound at this time of year and it is most likely that natural food source was the reason why the shark remained in the area over a matter of weeks.”

In a statement about the capture order, issued by Fisheries on19 December, Fletcher said capture gear was deployed in response to, “an increase in the number of day-time detections on consecutive during the leadup to Christmas”.

A second statement, on 20 December, said: “Department of Fisheries acting director general Dr Rick Fletcher said the shark has been detected again this morning close to beaches at Warnbro and capture gear will therefore be set this morning.”

The serious threat policy, which can be read here, says, “A capture order can be issued following a shark attack or, in the absence of an attack having taken place, multiple confirmed sightings or detections of a high hazard shark/s or sharks, in a location over a number of days, may still be considered to pose a serious threat in circumstances where there is considered to be a high risk.”

High-risk situations are described as the shark being within 1km of the coast and near well-used beaches. The policy also requires Fisheries to take environmental factors that may attract sharks into account.

MacLaren said she had referred the serious threat policy, which she described as a broadening of the previous imminent threat policy, to the Environmental Protection Authority for assessment. She said the policy was “light on detail” and had been “freely cited to justify killing, or attempting to kill, tagged sharks”.

“It is clear that far more individuals of south-western Australia’s white shark population could be killed under the new policy than the three-year drumline program proposed by the Barnett government last year, which was ultimately rejected by both the EPA and CSIRO on the grounds it was likely to endanger the white shark population.”

Guardian Australia asked Fisheries to clarify whether there had been any sightings of the Warnbro Sound shark. Bruno Mezzatesta, executive director of regional services, provided this response: “The decision on this occasion was based on multiple detections over several days and other factors as outlined in the department’s media alert issued on 19 December, noting numerous mitigation strategies were implemented in an attempt to negate the threat before the decision was made.

“A detection is a highly verifiable indication of the presence of a high hazard shark in high risk circumstances.”