PICS & VIDEO: Shark exclusion net keeps Fish Hoek beach safe
Cape Town - Putting up a shark exclusion net every day and then taking it down again at night has to be one of the most unique jobs in the world.
Shark Spotters Net Crew member Casey Bull says she enjoys her job because she knows she is keeping people safe from shark attacks.
“I enjoy what I do because I have always wanted to spend every day of my life on the beach,” she adds with a smile from popular Fish Hoek beach.
The net is utilised from spring to the end of summer every year, with full time daily usage from November until March (weather permitting) and intermittently as needed for the rest of the time.
Spring and summer is when there is the greatest overlap of people and sharks in the ocean.
The shark exclusion net, first deployed in 2013, weighs around 500 kilograms and is 350 meters in length. The net is contoured and touches the floor of ocean. It varies in depth from one meter to six meters at its deepest point.
Bull says she enjoys educating bathers about beach safety and is always willing to answer their questions about the shark exclusion net.
The project on Fish Hoek Beach supports ten employees from previously disadvantaged backgrounds. The team includes a skipper and nine net crew members.
The net crew deploys the net at around 8 am on a typical day.
Derek Bok, one of the crew members, grabs hold of the end of the thick chain used to anchor the net on shore and shakes it several times, creating a wave formation.
“I do that to warm my muscles,” he said.
Then the team, geared up in their wetsuits, get to work, systematically unpacking the net from the trailer. Crew members then wade into the ocean, holding sections of the net. With the help of the speedboat, they pull the net all the way across the bay to where it is anchored on the rocks at the furthest point from the shore.
It soon becomes apparent why Bok needed to “warm his muscles” as the operation is physically challenging.
Hooks at periodic intervals along the length of the net keep the net bunched up against a rope running along the top while it is being deployed. This makes it easier to work with. Once the net is in place the crew unhooks it so that it reaches the ground below.
The net has two more lead-laden ropes spanning the full length, one at the base and the other at the center, which enables the net to drop to the bottom of the sea bed.
As soon as the net is in place bathers can be seen taking to to the ocean. A couple with snorkels and goggles swim along the perimeter of the net as if to maximise the safe ocean space available to them.
After the gruelling deployment of the net, the team monitor it for the rest of the day to ensure that no marine animals have become entangled in it.
At around 5 pm, a vehicle arrives with the empty trailer and the skipper and net crew begin the onerous task of bunching up the net, shouldering and retrieving it, and then methodically loading it back onto the trailer.
Prior to 2013, shark activity and isolated incident of shark encounters caused public concern, which prompted the renowned Shark Spotters programme and the City of Cape Town to develop the shark exclusion net as an additional safety measure.
The sustainable, low maintenance and non-lethal net is made from flexible HDPE twine, and is the only one in the world designed to be deployed and retrieved on a daily basis. This makes it less susceptible to damage from rough seas and entanglement which mostly happens at night.
However, new technology is also being explored which will enhance the current shark spotting and prevention method. The Shark Spotters programme, along with the Institute for Communities and Wildlife in Africa at UCT and PatternLab SaRL, a research and development company specialising in data science and computer-aided vision from Switzerland, aims to deploy a low-cost, computer-vision-based shark detection algorithm which utilises a fixed camera at a high vantage point above the beach.
The success of this project will further increase the efficacy of shark spotters by mitigating the possibility of fatigue and human error.
African News Agency (ANA)