How to Catch a Shark
Rescuing a shark in the wild gives new meaning to managing work health and safety, writes Fleur Bull, head of health and safety, Sea Life
“How do you catch a shark?” was the opening headline on Sydney’s Channel 7 evening news in February as vision aired of a daring and successful grey nurse shark rescue off Magic Point in Maroubra, NSW.
The rescue mission resulted from local divers reporting sightings of a 1.5-metre female juvenile grey nurse shark. Dubbed ‘Tangles’, the shark had an elastic cord wrapped around its head and gills. From the local divers’ reports of its laboured breathing and their images, staff from Sea Life Sydney Aquarium and Manly Sea Life Sanctuary could see the shark was slowly dying. Dr Rob Jones, Sea Life veterinarian, said the elastic was cutting deeper and deeper into its neck.
The grey nurse shark is listed as a critically endangered species by the NSW Fisheries Management Act 1994. Despite their ferocious appearance, these sharks are placid unless provoked and are often referred to as the ‘labradors of the sea’. These animals are particularly vulnerable due to their late maturation and low breeding success. They reach sexual maturity at approximately eight to 10 years of age and give birth to one or two young only every two years, so the population grows very slowly.
NSW Fisheries, which is part of the NSW Department of Primary Industries, issued a permit to rescue Tangles. But such a permit had not been issued for more than 20 years, which meant no-one had any recent experience of catching a shark in the wild.
Although everyone has a responsibility to identify and eliminate or control hazards, as the head of health and safety, it was my job to give the health and safety sign-off to catch the shark in open water. My first thought was it would end up like a scene from the film Jaws: people screaming, blood gurgling and limbs missing. This was going to be a unique risk management issue. The importance of managing the risks and limiting exposure to the hazards would be critical during this shark rescue operation. The team’s safety had to remain the priority—Sea Life’s business principles state that safety is its number-one priority.
It wasn’t going to be a simple matter of jumping in a boat, launching it into the sea, catching the shark, removing the elastic, administering antibiotics and releasing the shark to live happily ever after.
Just like most health and safety professionals, my aim is to eliminate the hazards while still being reasonably practicable. However, eliminating the hazards in this operation was impossible —for one thing, the team was going to be diving into shark-infested waters.
Normally when a shark is injured it will stay close to the area it knows. The Magic Point area has two shark ledges teeming with life. This meant there would potentially be about 50 other sharks in the rescue location.
So deciding what was reasonably practicable was a fundamental question that needed to be answered. It needed to be balanced against the degree of harm and likelihood of injury. Importantly, the knowledge and competence of the divers needed to be considered, particularly the divers’ knowledge of shark behaviour.
Significantly, our divers could already tell when a shark or sharks were feeling threatened and/or unsure of a situation and identify the potential for aggressive shark behaviour. Emergency management and preparedness was also a key component in this operation. Although it was a different scenario, I was able to draw on my experience of responding to the earthquakes around the Canterbury region of New Zealand to help develop a plan of action. It was important to ‘prepare for the worst and expect the best’.
A team of 11 staff members was assembled to save Tangles.
The team was made up of Sea Life Sydney Aquarium and Manly Sea Life Sanctuary staff members and included a full dive team, Manly Sea Life Sanctuary general manager Ian Wood, veterinarian Dr Rob Jones and marine biologist Craig Thorburn.
The delicate operation needed to ensure shark attack and all other health and safety risks were ironed out before and during the rescue—for the sake of the staff involved and, of course, to ensure the best outcome for Tangles.
Over three weeks the designated team developed and confirmed a plan and produced a detailed risk assessment and hazard management controls (see examples below).
From drawing board to water
On the day of ‘Operation Tangles’ it was sunny, the weather forecast was spot-on and the team was given the green light. The team headed from Manly Cove with the aim of catching the shark. This time there was no Jaws music playing in my head, and the team was confident with the risk and hazard management plans we’d put in place.
The boat dropped anchor and the team completed the reconnaissance dive. The team’s only complication was the depth of the safety platform.
The management plan called for a safety platform to be located at a maximum depth of 10 metres. This was not possible due to sea swell movement.
However, the team located a safety platform at a depth of 16 metres. This was agreed to, on the condition that the team needed to increase the time required for divers to resurface, eliminating potential diving sickness.
Next, the sock (a device for capturing the shark) trial dive was completed successfully. No further adjustments were needed.
The rescue dive could now take place. It turned out to be the shortest of the dives and went without issue.
On the first attempt the team guided Tangles straight into the sock, enabling them to wrap a stretcher around her and bring her to the surface, where Dr Jones cut the cord and injected a course of antibiotics. Tangles was then released back into the water.
Ten weeks later, Tangles was spotted off Magic Point making remarkable progress, her wounds healing well.
Significant risks, hazards and controls
• Weather—before going ahead, the weather forecast and satellite imagery on the day were to be assessed and a visual check of wave height and wind speed was to be made at the dive location.
• Underwater safety platform—a reconnaissance dive was to be completed by two divers to confirm the location of a safe working platform at a maximum depth of 10 metres. Divers were to surface and discuss the situation with the dive team.
• Diver communication—a full-face mask was to be worn by each member of the dive team.
• No mid-water rescue attempt— the rescue was to only take place on the safety platform.
• A maximum of three rescue attempts—otherwise it would increase the risk of the shark becoming aggressive. If any diver felt that after one attempt the shark was already aggressive the rescue was to be postponed.
• Sock trial dive—the dive team was to practise setting the sock for capturing the shark. They were to surface to provide feedback and discuss the rescue procedure. The actual rescue dive was to proceed only if everyone was 100 per cent sure the hazards and risks were at an acceptable level.
• Divers’ knowledge and competence—divers needed aquarium and open-water shark diving experience, appropriate dive qualifications, and to have completed Sea Life’s internal diver training competences.
• Emergency management preparedness—the team needed to be able to respond to the many potential emergency situations.
Download the story in PDF How to Catch a Shark (PDF 1219 kB)
Published in National Safety magazine, July-August 2014.