Shark Cage Diving with Bronze Whaler Sharks

Bronze Whaler Sharks

Shark cage diving with Bronze Whaler Sharks offers the chance to encounter one of the large predatory shark species found around the South African coastline. Bronze Whaler Sharks can grow to around 3.5 metres in length, with particularly large individuals approaching 4 metres. Their name comes from their distinctive bronze-grey colouring. The term “whaler” is linked historically to whaling vessels, as these sharks were known to congregate around whale carcasses.

Guests encounter a Bronze Whaler Shark while cage diving in Gansbaai, South Africa

Shark Sightings

In the last few years, we have been cage-diving with Bronze Whaler Sharks regularly. As Great White Shark population numbers have declined around South Africa, this species has frequented our bay in large congregations during September to April. Sightings increase in the summer months as they come into shallow waters to give birth, breed, and chase their prey. Whilst in the area they are feeding on small fish species like mullet and sardine, octopus, and smaller sharks that swim along the bottom of the sea floor.

Bronze Whaler Sharks are schooling sharks so generally we get more than one shark at a time visiting the cage. This provides our clients with fantastic and often constant shark activity throughout the trip. Sometimes having up to 30 sharks around the boat, being in the cage can be like being in the middle of a big school of sharks!

For guests, every Bronze Whaler shark cage diving experience can be different. The number of sharks around the boat can vary with environmental conditions, prey availability and shark movements. When several Bronze Whalers are present, guests may have the opportunity to observe individual sharks moving around the cage, interacting with one another and displaying their natural behaviour at close range.

Relationships

The males and females of this species do not live together. The females form large schools, whilst the males form smaller schools and tend to only visit the female schools during the breeding season. In Gansbaai, the Bronze Whaler Sharks that we see are predominantly large mature females with the occasional male recorded. There is evidence of breeding occurring in the area as many of the females recorded have bite marks on them. When sharks mate the males bite down onto the sides of the female and we often observe the females with fresh bite marks This indicates that breeding is occurring in the area, making it a significate location for this species.

Scarring and bite marks on female Bronze Whaler Sharks

Reproduction

Bronze Whaler Sharks give birth to live young rather than laying eggs. During development, the embryos are nourished through a placenta-like connection to the mother, a form of reproduction known as placental viviparity.

Bronze Whalers are slow-growing sharks that take many years to reach maturity. Females have relatively small litters after a long pregnancy, meaning populations reproduce slowly. This makes the species particularly vulnerable to fishing pressure, as populations can take a long time to recover when numbers are reduced.

The Bronze Whaler Shark (Carcharhinus brachyurus) is currently classified as Vulnerable on the IUCN Red List of Threatened Species, highlighting the importance of responsible fisheries management and the conservation of important coastal habitats.

Geographic Location

Bronze Whaler Sharks have a wide distribution in temperate and subtropical waters around the world. In southern Africa they are highly mobile, with tagged sharks recorded moving between South Africa, Namibia and Angola. Their movements can be influenced by factors including season, water temperature and the availability of prey.

Today, Bronze Whalers have become an important part of the shark encounters experienced in Gansbaai. Providing an opportunities to observe and learn about a species whose movements connect different parts of the southern African coastline.

Predator–Prey Relationships

Bronze Whaler Sharks share South African coastal waters with other large predators, including Great White Sharks. At White Shark Projects, we have occasionally observed both species during the same trip, providing a fascinating opportunity to see how different shark species use the same environment.

Bronze Whalers often occur in groups, whereas Great White Sharks are more commonly encountered individually. When a large Great White enters an area where Bronze Whalers are present, their behaviour may change and they can become less conspicuous. Although large Great Whites are capable of preying on other sharks, we have not personally witnessed a Great White preying on a Bronze Whaler in Gansbaai.

Seasonal Sightings

Bronze Whaler sightings in Gansbaai can vary considerably throughout the year. Their movements are influenced by changing environmental conditions, including water temperature and the availability and movement of prey. As highly mobile sharks, Bronze Whalers can travel considerable distances along the southern African coastline.

These movements also connect Bronze Whalers with one of South Africa’s most remarkable marine events, the annual Sardine Run, when large numbers of predators gather around migrating shoals of sardines along the country’s eastern coastline.

Shark sightings are never guaranteed, and the species encountered in Gansbaai can change with the seasons and from year to year. This changing environment is part of what makes long-term observations from the area so valuable for understanding South Africa’s shark populations.

Bronze Whaler Sharks remain an important part of Gansbaai’s marine ecosystem and shark encounters.