Diving into the world of sharks off the KZN coast through the sense of sound
A large aggregation of the endangered scalloped hammerhead sharks pictured in the Protea Banks MPA. (Photo: Rolan Mauz, WILDOCEANS)
Sharks might be scary to some, but they are a vital part in maintaining the health of our oceans, and knowing more about them helps us humans be better cohabitants on our big blue planet.
Last year South Africa recognised the importance of our oceans by approving 20 new and expanded Marine Protected Areas (MPAs), upping our ocean protection from 0.4% to 5%.
One of these new spots is the Protea Banks reef system off the south coast of KwaZulu-Natal, including submarine canyons populated by our toothy friends - and WILDOCEANS is making it their mission to conduct a study of shark movement using the technology of sound.
The organisation deployed their Angra Pequena research vessel to retrieve telemetry receivers that were deployed last year in July. These receivers - or listening stations - pick up and record unique signals from acoustic tags inserted onto tagged fish and sharks and allow researchers to track the movement patterns of these species.
These receivers went down to depths of 80 to 90 metres at the head of each of the three big submarine canyons that lie seaward behind the Protea Banks reef system, and there's much excitement around what scientists might uncover.
Jean Harris, executive director of WILDOCEANS, said that this study is the first of its kind in South Africa and one of only a few worldwide.
“The aim is to study the movement of sharks along the KwaZulu-Natal coast. This part of the project that is led by Dr Matt Dicken of the KwaZulu-Natal Sharks Board, aims to understand the importance of canyon heads as critical habitat for sharks, especially species such as tiger, ragged-tooth and Zambezi.”
Youth for MPAs representative and Ocean Steward Jamila Janna, whose role on the expedition was to help spot the buoys attached to the equipment when it surfaced, said that she really enjoyed being exposed to different people and seeing how diverse a field can get.
“Seeing how many components there are to marine biology and also just spreading the message of conservation - it’s fun and I just love learning. I really like experiences like this and love this kind of work.”
Youth 4 MPAs representative and Ocean Steward Jamila Janna pictured during a Canyon Connections expedition on board RV Angra Pequena. (Photo: Kelvin Trautman, WILDOCEANS)
One of the cool queries they have to uncover is about the movement of scalloped hammerheads - the species has only been tagged in Mozambique so far and if they pick up signal among the large frenzy that lives off the KZN coast, it means that these sharks like to travel for visits across the border.
Even cooler, this telemetry research will be featured in a marine documentary series - Our Oceans - set to be released mid-2019. It will follow the marine expeditions onboard the RV Angra Pequena, the spectacular beauty of South Africa's marine ecosystems and the people and communities who have a close bond with our big blue.
Ezemvelo KZN Wildlife Scientist Tembisa Jordaan and WILDOCEANS executive director Dr Jean Harris pictured in Duiker Island, Hout Bay before a research dive that was filmed as part of Our Oceans series. (Photo: WILDOCEANS)