Bryde’s Whale (Balaenoptera edeni)

Bryde’s whales were named after the Norwegian Consul to South Africa, Johan Bryde, who helped set up the first whaling station at Durban, in 1908. Fortunately, their stocks were not exploited as badly as other large whales, giving them a current worldwide population of 90,000. They are listed by the IUCN as Data Deficient as not much is known about this species; especially as they were frequently mistaken for the similar sei whale (Balaenoptera borealis), so numbers were hard to estimate in the past.

These whales range from 10-15.6 metres and 12.1-20.3 tons. They are a difficult species to identify as they have similarities to both the sei and minke whales. They are dark grey with a slightly paler underside, have a small sickle shaped dorsal fin located two-thirds along the back, have a narrow, 3-4m tall blow, and have three ridges extending from the blowholes to the tip of the rostrum. At close range these three ridges make them easier to distinguish, but from a distance Bryde’s whales can often be identified if you see the blowhole disappear before the dorsal fin appears. However, these whales are incredibly elusive as they surface at irregular intervals and continually change direction appearing 10 minutes later up to a kilometre away. They can dive for up to 20 minutes and reach depths of up to 300 metres. Usually found singly or in pairs, they have however, been seen in loose aggregations of up to 20 individuals when feeding.

Unlike most baleen whales, the Bryde’s whales found off the South African coast are non-migratory (click here for map). They do however migrate seasonally as they follow shoals of fish up and down the coast, feeding opportunistically. They are known to feed on sardines, anchovies, maasbankers and squid. Bryde’s whales exploit the activities of other predatory animals such as penguins and dolphins who have already herded the schooling fish into concentrations known as “baitballs”. The whale then swims from underneath the shoal with mouth open wide and throat distended to swallow the hundreds of fish above. This method is called ‘lunge-feeding’ and is used by most other rorqual whales.

Bryde’s whales spend their entire lives in warm waters, feeding all year round, so they have no specific breeding season and calves can be born any time of the year. However, new-born calves are usually seen in late summer/autumn. They have a gestation period of 11-12 months and calves are weaned at 6 months. Bryde’s whales give birth every two years and calves can be between 3.4 and 4 metres in length and weigh up to a ton, at birth.