Sand tiger sharks
The team was primarily interested in the coral reef off the coast. The reef runs at a depth of 15 to 40 meters parallel to the coast south of Durban. The diving sites were reached after about 15 â€“ 20 minutes by boat. With the high waves, the trip is not for anyone with a delicate stomach! Although the plan was to feed the fish with JBL MariPearls, many of the team members involuntarily fed the fish on the trip out there!
With water temperatures of 22 to 24 °C, thicker wet suits were definitely called for! The water was relatively cloudy and visibility was restricted to about 10 to 15 m.
The coral reef is very impressive in places. Hard and soft corals, sponges and other invertebrates cover the ancient reef stone. The coral communities cannot be compared with “normal“ tropical reefs. Amongst the fish, many species can be seen which are typical for regions close to the Antarctic. The mixture of tropical and coldwater species is astounding!
The shark course with Andy Cobb had prepared the team for their encounters with sand tiger sharks. The shark usually remain in one area and are not very shy at all. However, if divers become impatient and get too close to the creatures, they will sometimes flee to deeper waters for several days.
The Swiss team member, Michel Comte, carried out underwater feeding trials with JBL MariPearls. The strong current made this experiment highly complicated. Nevertheless, many species of fish could be observed feeding. As in previous trials, it was noted that chaetodon species (butterfly fish) were not interested in the food. Just for fun, food granulate was sprinkled on the surface of the water. The skipper observed from the boat that the mantas noticed the food immediately (they were over 3 m long!) and eagerly filtered it from the water.
Dr. Ludwig Neurohr took water samples at various depths, which were then analyzed by the whole team on land. (For data see gallery Research).