August 06, 2015 by dyertrust
Jacques Costeau once said the best way to observe a fish, is to become a fish and this is exactly how one feels while descending on this dive! As we dropped down beneath the water surface our line of sight was immediately consumed by the vast shoals of Yellowtail comrading together like foot soldiers rushing to battle. Cow nose sting rays elegantly swept in and out between them. Impressive Kobaljeu and Spotted Grunter moved stealthily so as not to get in the way, whilst cartoon like Musselcracker or Poenskop hovered in their own little worlds. Every fish had its rank and knew its place. As we looked carefully on the floor, tiny nudibranchs hid themselves perfectly camouflaged amongst boulders. It truly was an enlivening experience. Glancing out the window at the children’s faces was equally as magical, to see their sheer bewilderment- from the perspective of the creatures swimming in front of them. It was a surreal juxtaposition to be the human intertwined in the world of a captive fish which we found very entertaining! Nicole beamed from ear to ear whilst waving excitedly at us through the window. We waved back, and noted her expression change as the silhouettes of two large Ragged tooth sharks approached us.
The Ragged tooth shark (Carcharias taurus) is quite different to the Great White. I like to describe them as the Jimmy Nail of the shark world (Jimmy Nail was the guy who sang the 90s hit crocodile shoes. My mum used to say he’s so ugly he’s attractive!). Raggies have an undue menacing appearance with their small beady eyes and snaggle like teeth. Pre 1990s fishermen targeted the species as they were perceived maneaters throughout much of their distribution.
This was before research confirmed they are very placid and actually extremely vulnerable to exploitation due to their slow reproduction. The two oceans aquarium have supported some of South Africas most critical ragged tooth research including the tagging and releasing of various sharks. Maxine was a large female ragged tooth caught in the KZN shark nets in 2004. She was rehabilitated in the aquarium and migrated far east when released with satellite tags. The species makes incredible large scale migrations from the Western cape to the East coast annually in SA. Maxine became a real ambassador highlighting these movement patterns during the popular public campaign.
Our dive lasted around 45 minutes, then Ilze and I surfaced with huge smiles very contented! Angie even gave Ilze a Raggies tooth which she said was especially for little Nicole. It was quite the luxury dive experience with a clean towel and warm shower waiting for us after- we did not even have to de-kit our SCUBA gear- Angie and the team had it all covered!
The great thing about the dive in the I&J predator tank is its warm, its crystal clear and there’s an absolute 100% guarantee of seeing the sharks and other predators up close and personal! The staff go out of their way to ensure your comfort and safety. I would definitely recommend this as a must do dive in the Western Cape, especially if the Cape of storms is living up to her reputation!
A brand new predator tank is in the process of being built at the Two Oceans, which Im told will undoubtedly impress. As tourism and conservation partners the Two Oceans aquarium, Marine Dynamics and Dyer Island Cruises go back over a decade. It is a simple relationship; each business is geared around the same passion and drive for marine education and conservation. In fact, one of MD and DICS resident skippers Pieter du Toit was a shore angler who helped catch and tag ragged tooth sharks in Struisbaai during Maxines campaign in 2004!
Two weeks ago the Two Oceans donated 100,000 ZAR towards the building of our African Penguin and Seabird Sanctuary (APSS) which was an integral building block towards the development of the facility in Gansbaai. For more information on this see
Previous surveys have employed underwater visual census and capture survey techniques. The detection power, environmental impact and financial sustainability of these methods have limited their implementation, especially in the cold Benguela upwelling–? driven ecosystems on South Africas west coast. The baited remote underwater video system (BRUVs) has been tested as a standard, non–?extractive methodology that can be applied throughout South Africas near–?shore marine habitat areas.
BRUV surveys have been performed in both protected and exploited areas in South Africa, including False Bay, Bettys Bay, Stilbaai and Tsitsikamma. The standard BRUVs provide data on habitat, species diversity and abundance. The stereo–?BRUVs variation can give estimates of fish length. While fish length is a useful metric because it can be converted to fish size structure data, the stereo–?BRUVs require more complicated equipment for the deployment and additional software and time for the analysis of the length data. Therefore, the single camera BRUVs are more practical as a standard survey tool across South Africa.
The BRUV system operates by lowering a camera rig to the sea floor and recording approximately one hour of footage for later analysis of the habitat, number and behavior of the species within view. Deployments can be made simultaneously in groups of up to four rigs. Cameras are deployed at least 150 m apart to maintain sample independence.
This will be the first study of its nature around Dyer Island.
Staff from both the Dyer Island Conservation Trust as well as CapeNature will be trained to utilize BRUV systems during this study and in the long term this will become a monitoring project for the Dyer Island Conservation Trust and the International Marine Volunteers in the Greater Dyer Island Region.
We thank one and all who attended this evening, it was by far one the most interactive audiences at our Marine evenings.
All visitors was also reminded that the African Penguin and Seabird Sanctuary is nearing completion, and that anyone is welcome to stop by to see the progress on site there will not always be people on had to show them around, but with the sponsorship of the horticultural layout by the Grootbos Foundation, it is worthwhile to stop and see the wonderful progress of the facility.
For any queries you are welcome to contact the DICT at 0829075607