The Indian Ocean Humpback Dolphin is South Africa's rarest coastal cetacean. These animals get their name from their accumulated fat hump under their dorsal fin and have a range of up to 500km.
Conservation status: Endangered
Humpback Dolphins are considered to be an endangered species, with small populations of these toothed whales living very close to shore, typically in 30m of water or less. Their proximity to land makes these animals particularly vulnerable to human influence.
While capturing a small pod of humpback dolphins always makes for a thrilling addition to every photographer’s portfolio, it’s the up close and personal images which really capture the grace of this beautiful species.
Frequently Asked Questions
Whale spotter Vumanie (Kira) Matiwane tells us about the local humpback dolphin.
How large are these dolphins?
Typically, the Humpback Dolphins reach a length of between 2.5 to 2.8m in length. Calves are born at a size of around 1m.
Diet – What do the dolphins eat around Dyer Island?
The Humpback dolphins mainly eat fish that can be found in shallow waters such as mackerels and mullets. They also enjoy feeding along the rocky reef systems in our bay.
Behavior – Do dolphins have a social life?
Humpback Dolphins travel alone or in small groups and we observe them in pods ranging from 1 to 12 individuals. In the Dyer Island area, we most commonly see groups with only 2 or 3 dolphins. In other areas, the biggest group ever observed was composed of 25 dolphins.i
Births occur predominantly in late summer and Autumn although calves have been recorded at other times in the year . Females have usually one calf every three years. The female is sexually mature between 5 and 12 years old, the male between 10 and 12 years. The gestation period (pregnancy) is one year. The calf measures approximately 90 to 130 centimetres long at birth with an average weight of 30 kg, and is born tail first.
Threats – What are the main threats to dolphins?
Due to their habitat range, these dolphins are extremely vulnerable to human activities such as boating, shark nets and also pesticides used on land from farming and agriculture. As they live in shallow waters, they are more likely to be exposed to every type of pollutant coming from the rivers to the seas. The toxins that are entering the marine environment can concentrate in the dolphins’ fat (via contaminated fish) and can negatively affect their health. They also get entangled in the nets that are used to prevent the sharks from coming close to the beaches, as well as in fishing nets. Dolphins are known to be curious animals and can also become easily entangled in pieces of marine litter, such as pieces of plastics, ropes, etc.
Identification – How can we recognize different individuals?
Each dolphin has a unique dorsal fin, both with regards to shape and notches along the edge of their fins. Dorsal fins can therefore be used to recognize different individuals. We have already identified over 35 humpback dolphins in the area using this method of photo identification.
Fun Fact: Unlike most other dolphin species, humpback dolphins are largely solitary animals who don't typically form large groups.