Bryde's Whale
The Bryde's Whale (pronounced 'Broodahs') has a worldwide tropical to warm temperate distribution. It does not migrate; instead it moved from inshore to offshore waters, following food, and is chiefly resident year-round.
Classification: In 1878, Anderson described and named the Bryde's Whale, Balaenoptera edeni. However, in 1912 Olsen described a species seen off South Africa and named it Balaenoptera brydei after the Norwegian Counsel to South Africa, Johan Bryde. Eventually, it was found that both descriptions referred to the same species, and so the original 1878 classification was retained, with the common name deriving from the 1912 classification.
Local Names: Tropical Whale.
Description: This cetacean is similar in both size and appearance with the Sei Whale, and the two are often confused. However, the Bryde's Whale is generally shorter, stocky and slender, with a well-defined dorsal fin set two-thirds back down the body. The tail stock is compressed, with broad, notched flukes, and pointed flippers. The body colour is dark grey with some white coloration on the chin and throat, occasionally with paleness down the back between head and dorsal, extending down the flanks. Pock marks from parasites or small sharks add a mottled appearance, and there are two distinct ridges on the head, either side of the midline. There are between 40-70 throat grooves, and 500-730 baleen plates per animal, the maximum length of which is about 60cm. Females are generally larger than males, and the Bryde's Whale measures about 13-16m in length and weighs between 16-25 tonnes.
Recognition at Sea: The two ridges on the head either side of the midline easily distinguish this whale from others. The blow is vertical, 3-4m high in a 'cloud'.
Habitat: This species is found in either inshore and offshore waters, preferrably those with a temperature above 20°C.
Food & Feeding: The Bryde's Whale consumes whatever shoaling prey is available, and often exploits the activities of other predators, swimming through and engulfing the fish they have herded. Therefore, it is frequently found in areas of high fish abundance, along with seabirds, seals, sharks and other cetaceans.
Behaviour: Bryde's Whales are not gregarious in manner and either swim alone or in pairs. The largest group sizes of 10-23 animals are usually loose congregations covering a few square kilometres when feeding. The Bryde's Whale dives to a maximum of about 300m and communicates via moans, pulses, clicks, and grunts, as well as breaching.
Longevity: Approximately 50 years.
Estimated Current Population: 40-80,000 animals.
The Influence of Man: Many Bryde's Whales were included in the 1960s catches of Sei Whales in the North Pacific. They have only been systematically exploited in this region of the world and this ceased when the IWC's Moratorium on Commercial Whaling was introduced in 1986. Therefore, in comparison with other rorquals, the species had been largely overlooked as a resource and overall, the Bryde's Whale is not believed to be in danger nor at depleted levels.
Source: CETACEA
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