Just another day at the office.
Yesterday the Two Oceans Aquarium collections team was called out to Strand by the City of Cape Town to help free a shark that had been stuck in one of the tidal pools at Harmony Park Resort since Friday. No one knew what kind of shark it was and guesses around the office included spotted gully shark or pyjama shark. Turns out our guesses were wrong … it was in fact a male broadnose sevengill shark (Notorynchus cepedianus), aka cow shark.
City of Cape Town Coastal Management Officer Sarah Chippendale met us on the scene on what was a rainy, windy and frankly cold (and early) Thursday morning on the beach. A fair-sized crowd also gathered as Operations Manager Tinus Beukes and his team members Simon Brill and Deen Hill walked down to the tidal pools, clad in wetsuits and carrying nets, fins, stretchers, goggles and snorkels.
The first step was to read the shark’s mind. What would his movements be and how would the team be able to get close enough to him to get him into a stretcher while making sure the animal experienced minimal stress?
Tinus reckoned the shark was doing laps around the pool and based on that he and Simon moved to the north of the pools while Deen jogged to the south end and jumped into the water, swimming towards the shark.
Since wild animals should always be handled with care and caution, and since safety always comes first (for the people and the animals), Deen decided not to force the shark into the net, but instead followed it closely and gently coaxed it towards Tinus and Simon. This went on for some time and the team was close to the northern edge of the pools when we heard Deen’s incredulous shout: “I think it’s a cowshark?!”
Simon and Tinus then ran over to where Deen and the shark were and a light scuffle broke out as the men tried to restrain the shark and get it into a stretcher. By the time they did this it was a fact – a male sevengill shark had been trapped in the tidal pool.
This was a particularly special moment as the Two Oceans Aquarium together with Woolworths is supporting Dr Alison Kock’s five-year study on these mysterious sharks. The thing is, so far Dr Kock has only found and tagged female sevengills (around the Miller’s Point area), so finding and possibly being able to tag a mature male was a massive coup for her research project.
Simon and Deen were ready to release the shark but Tinus asked them to hold on and to move him into a transport tank conveniently attached to the Aquarium’s bakkie (you never know when this may come in handy). Tinus knew that Alison would be thrilled to be able to tag this male sevengill, so he telephoned her as well as our resident vet Dr Georgina Cole (who is actually on study leave) and told them to hurry to the scene.
Together the doctors would insert an acoustic telemetry tag as well as a microchip, and would take blood and fin samples, muscle biopsies and various measurements.
“Going out expecting to find a gully shark and coming across a male cowshark was fantastic,” says Simon. “The first challenge was removing him from a fairly large pool, which we managed to achieve without too many hassles. Then, keeping the animal happy and healthy till the vet arrived posed the second challenge.”
Alison and Georgina arrived, as did Alison’s research assistants Dave van Beuningen (Shark Spotter research assistant), Leigh de Necker (MSc student at UCT doing her thesis on sevengill feeding ecology) and Tamlyn Engelbrecht (MSc student at ICT doing her thesis on sevengill spatial ecology). Pippa Elrich of the Save Our Seas Foundation (which supports Dr Kock’s project as well as a number of other shark research programmes) was also there to document the impromptu but important tagging process.
Tagging and performing biopsies on a wild animal, especially a wet one, is tricky business. Utmost care is given to the handling of the shark, and Dr Cole monitored our sevengill’s health closely before deciding to go ahead with the minor procedures.
It takes practise, preparation, cleanliness, care and speed, gentleness and above all focus to perform these tasks without stressing the shark too much. Communication between team members is vital too – everyone was certain of their role and followed Dr Cole’s instructions closely.
Teamwork was everything on the day and the visceral excitement (and a fair number of onlookers and cameras) did not get in the way of the highly professional and fast operation.
The number-one priority was to get the shark back in the water as quickly as possible.
Tinus decided that it would not be wise to release the shark back into the rocky shore of Harmony Park, as Deen and Simon would be unable to swim with the animal for a while to make sure that it was in good nick. So, extremely slowly, they drove up the road to the Gordon’s Bay harbour where they could release the shark by swimming out and along with it.
"I am thrilled we have tagged this large male, hopefully he is the first of many more and I look forward to tracking his progress over the next few years,” said Dr Kock. “I am very thankful to everyone involved for contributing to this successful story."
“Once the tag was inserted we woke him up and released him back into his natural environment,” says Simon. “All in all it was a fantastic and rewarding day for all involved.”