The sei whale (Balaenoptera borealis) is a baleen whale and the third-largest rorqual after the blue and fin whales, growing to about 19.5 metres and weighing as much as 28 tonnes. Its body is usually dark steel grey with irregular light grey to white markings on the underside, and it has a tall sickle-shaped dorsal fin and very fine, curly baleen bristles that set it apart from other rorquals. It is among the fastest of all cetaceans, reaching 50 to 55 kilometres an hour over short distances. Found in most oceans but avoiding polar and tropical waters, it migrates each year between cool subpolar waters in summer and temperate or subtropical waters in winter, feeding on copepods, krill and other zooplankton. Commercial whaling killed over 255,000 sei whales in the nineteenth and twentieth centuries; the species is now internationally protected and is listed as endangered on the IUCN Red List, though numbers are increasing.
Facts
Classification
Population Trend System (Realm) ThreatsBiological Resource Use 1 Relationship to People Living or Extinct Conservation Status Body Size Band Activity Pattern Comparison
NatureServe Rank CITES Appendix CITES Appendix Connections
Child Taxon Of
Source Sei whale (Wikipedia)
In Biome
Source Sei whale (Wikipedia)
In Ecosystem
Source Sei whale (Wikipedia)
In the Other Atlases
Found In
Also in Geography Atlas: where this subject is found.
Source Sei whale (Wikipedia)Range and migration, AtlanticQuote, Range and migration, Atlantic
In the North Atlantic, its range extends from southern Europe or northwestern Africa to Norway
Also in Geography Atlas: where this subject is found.
Source Sei whale (Wikipedia)Range and migration, IndianQuote, Range and migration, Indian
Sei whales have been recorded from northern Indian Ocean as well
Also in Geography Atlas: where this subject is found.
Source Sei whale (Wikipedia)Range and migration, PacificQuote, Range and migration, Pacific
In the North Pacific, it ranges from 20°N to 23°N latitude in the winter
Sources
1. Sei whale (Wikipedia)
Range and migration, living
Sei whales live in all oceans, although rarely in polar or tropical waters.
Lead, population trend
though populations are increasing
Lead, CITES northern
The Northern Hemisphere population is listed under CITES Appendix II
Lead, CITES southern
the Southern Hemisphere population is listed under CITES Appendix I
Lead, diet
It is a filter feeder, with its diet consisting primarily of copepods, krill, and other zooplankton.
Lead, lifespan
with a lifespan of 70 years
Lead, whaling, people
Following large-scale commercial whaling during the late 19th and 20th centuries, when over 255,000 whales were killed
Range and migration, Atlantic
In the North Atlantic, its range extends from southern Europe or northwestern Africa to Norway
Range and migration, Pacific
In the North Pacific, it ranges from 20°N to 23°N latitude in the winter
Range and migration, Indian
Sei whales have been recorded from northern Indian Ocean as well
Lead, realm
It inhabits most oceans and adjoining seas, and prefers deep offshore waters.
In Group: Cetaceans (Whales, Dolphins and Porpoises), Lead
is a baleen whale
Child Taxon Of: Balaenopteridae, Taxonomy
Sei whales are rorquals (family Balaenopteridae)
In Biome: Open Ocean, Range and migration
Sei whales are pelagic and are typically found in basins in oceans or open seas.
In Ecosystem: Antarctic Peninsula, Vocalization
off the coast of the Antarctic Peninsula
View the Source2. NatureServe: NatureServe Explorer: Balaenoptera borealis
NatureServeGlobal rank (roundedGRank)Quote, Global rank (roundedGRank)
"roundedGRank": "G5"
3. SeaLifeBase: Balaenoptera borealis, Sei whale
SeaLifeBaseIUCN Red List StatusQuote, IUCN Red List Status
Endangered (EN) (A1abd); Date assessed: 25 June 2018
4. Ecological Archives E095-178 (Wilman et al. 2014): EltonTraits 1.0 mammal diet data
Ecological Archives E095-178 (Wilman et al. 2014)Row Balaenoptera borealis, columns Activity-Nocturnal, Activity-Crepuscular, Activity-Diurnal
Balaenoptera borealis Balaenopteridae 60 0 0 40 0 0 0 0 0 0 Ref_43 ABC M A 0 0 1 Ref_1
Row Balaenoptera borealis, column BodyMass-Value (20000000 g)
5342 Balaenoptera borealis Balaenopteridae 60 0 0 40 0 0 0 0 0 0 Ref_43 ABC M A 0 0 1 Ref_1 ABC 20000000
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