Description & Behavior
Bryde’s whales, Balaenoptera edeni (Anderson, 1878), (“Bryde’s” is pronounced “broo-dess”) are commonly called tropical whales, Eden’s whales and Kochi whales and like all rorquals (Family Balaenopteridae, the family that includes the blue whale, fin whale, humpback whale, minke whale, and sei whale) these long, slender whales are much more streamlined than other large whales.
Bryde’s whales are dark gray in color on the dorsal side with a yellowish white ventral side. They are the second smallest rorqual with an average length of 12 m, although the female is usually about 0.3 m longer than the male. Bryde’s whales have two blowholes located on the top of the head. Bryde’s whales are often confused with sei whales; however, the Bryde’s whale has three parallel ridges in the area between the blowholes and the tip of the head.
The flippers are small compared body size. The prominent dorsal fin is sickle shaped. Instead of teeth, these whales have two rows of baleen plates. These plates are located on the top jaw and number approximately 300 on each side. Each baleen plate is short and wide, 50 cm by 19 cm. Mass: 12,000-20,000 kg. Thought to live between 50-70 years.
World Range & Habitat
Bryde’s whales are found in the Atlantic, Pacific, and Indian Oceans and off the coast of Ethiopia in warm temperate and subtropical waters. Populations exist mainly in warmer waters (~20°C). They are not migratory, but they do move between inshore to offshore waters to follow food.
Feeding Behavior (Ecology)
Bryde’s whales, Balaenoptera edeni, feed almost exclusively on pelagic fish (pilchard, mackerel, herring, and anchovies), pelagic crustaceans (shrimp, crabs, and lobsters), and cephalopods (octopus, squid, and cuttlefish). 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. They are therefore frequently found in areas of high fish abundance, along with seabirds, seals, sharks, and other cetaceans.
Breeding occurs year-round for Bryde’s whales. Sexual maturity is reached at 10 years of age for males and 8 years of age for females. The gestation period is approximately 12 months. Most Bryde’s whales bear 1 calf. Calves are around 4 m at birth and weigh 1,000 kg.
Conservation Status & Comments
Some populations of Bryde’s whales were seriously depleted as a result of historical whaling practices. As a result of the 1986 Moratorium on Whaling, they are protected worldwide. Estimated Current Population: 40-80,000 animals (2000).
Bryde’s whales are classified as Data Deficient on the IUCN Red List of Threatened Species:
DATA DEFICIENT (DD)
A taxon is Data Deficient when there is inadequate information to make a direct, or indirect, assessment of its risk of extinction based on its distribution and/or population status. A taxon in this category may be well studied, and its biology well known, but appropriate data on abundance and/or distribution are lacking. Data Deficient is therefore not a category of threat. Listing of taxa in this category indicates that more information is required and acknowledges the possibility that future research will show that threatened classification is appropriate. It is important to make positive use of whatever data are available. In many cases great care should be exercised in choosing between DD and a threatened status. If the range of a taxon is suspected to be relatively circumscribed, and a considerable period of time has elapsed since the last record of the taxon, threatened status may well be justified.
References & Further Research
Research Balaenoptera edeni @
Barcode of Life ~ BioOne ~ Biodiversity Heritage Library ~ CITES ~ Cornell Macaulay Library ~ Encyclopedia of Life (EOL) ~ ESA Online Journals ~ FishBase ~ Florida Museum of Natural History Ichthyology Department ~ GBIF ~ Google Scholar ~ ITIS ~ IUCN RedList (Threatened Status) ~ Marine Species Identification Portal ~ NCBI (PubMed, GenBank, etc.) ~ Ocean Biogeographic Information System ~ PLOS ~ SIRIS ~ Tree of Life Web Project ~ UNEP-WCMC Species Database ~ WoRMS