Taxonomy
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Mammal
- Order
- Artiodactyla
- Family
- Balaenopteridae
- Genus
- Balaenoptera
- Species
- Balaenoptera borealis
Habitat
This subspecies primarily inhabits the open waters of the Southern Hemisphere, including subpolar and temperate oceans. They prefer deep pelagic zones and undertake seasonal migrations from Antarctic feeding grounds in summer to warmer breeding areas in winter.
Diet
Southern sei whales mainly feed on krill, small schooling fish like lanternfish, and squid by using their baleen to filter prey from the water. They employ lunge feeding techniques, swimming rapidly through dense patches of food. Feeding activity peaks in the summer months in polar regions.
Behavior
Southern sei whales are typically solitary or found in small groups of 2-5 individuals, though larger aggregations can occur in feeding areas. They are fast swimmers, capable of speeds up to 50 km/h, and undertake long annual migrations covering thousands of kilometers. They are generally less vocal and acrobatic than other whales, with occasional breaching or surfacing behaviors.
Conservation Status
The Southern sei whale is classified as Endangered by the IUCN, with populations slowly increasing after historical whaling declines. Major threats include ship strikes, entanglement in fishing gear, and climate change impacts on prey availability.