![]() ![]() This migration of fish is a critical feeding opportunity for many predators of sardine and anchovy and ‘feeding frenzies’ involving Bryde’s whales, sharks, fur seals, seabirds, predatory fish and common dolphins occur. They are also seen following the spectacular natural event known as the ‘Sardine Run’ into Kwazulu-Natal waters in winter. The average speed common dolphins keep is 7 km/h, but they can reach speeds of 35 km/h and have been reported to cover 120km in 24 hours.Ĭommon dolphins feed primarily on pelagic shoaling fish such as pilchards (Sardinops ocellatus), mackerel (Scomber japonicus), squid (Loligo spp) and anchovies (Engraulis japonicus). They can often be seen travelling with Bryde’s whales and when going at speed they make the ocean look like it’s boiling. They can travel at high speeds for extended periods of time and regularly bow ride boats and ships. School sizes can range from 1 – 10 000 individuals, but the average group size is around 600. Males are sexually mature at 10 – 12 years of age. Females reach sexual maturity at around 8 years of age and they will calve every 2 -3 years. Although they can give birth all year round, there is a peak in births during summer (Feb/Mar). They have a gestation period of around 11 months and calves are approximately 1m at birth. They reach lengths of 2.2 m (females) to 2.5 m (males) in length and can weigh up to 140 kg. They are dark grey dorsally (on the back) and pale underneath (belly). This is a golden-yellow colour nearest the head and light grey towards the tail. Their presence in the bay has been related to the seasonal movements of their prey (mainly sardine and anchovy).īoth long and short-beaked common dolphins are easy to distinguish from other dolphins by the ‘hourglass’ marking on the side. In Plettenberg Bay common dolphins (long-beaked) can be seen throughout the year, but predominantly in summer and early autumn. The home ranges of the two species over-lap, but the short-beaked is primarily oceanic, while the long-beaked is more tropical, living within the continental shelf and in coastal waters. Until fairly recently, both were considered to be the same species with great variation in appearance, but due to many years of research, are now treated as separate species. Off Southern Africa two species of common dolphin can be found, long-beaked (Delphinus capensis) and short-beaked (Delphinus delphis). ![]()
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