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Sei Whale

Mammals

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
Diet
Filter Feeder 1
Population Trend
Increasing 1
System (Realm)
Marine 1
Threats
Biological Resource Use 1
Relationship to People
Hunted or Fished 1
Living or Extinct
Yes 1
Conservation Status
Endangered 3
Body Size Band
Giant 4
Activity Pattern
Diurnal 4
Lifespan
70 1
Comparison
NatureServe Rank
G5 Secure 2
CITES Appendix
Appendix I 1
CITES Appendix
Appendix II 1
Connections

Child Taxon Of

Balaenopteridae, Taxa
Source Sei whale (Wikipedia)

In Biome

Open Ocean, Biomes
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, Atlantic
Quote, 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, Indian
Quote, 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, Pacific
Quote, 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 Source
2. NatureServe: NatureServe Explorer: Balaenoptera borealis
NatureServeGlobal rank (roundedGRank)
Quote, Global rank (roundedGRank)
"roundedGRank": "G5"
View the Source
3. SeaLifeBase: Balaenoptera borealis, Sei whale
SeaLifeBaseIUCN Red List Status
Quote, IUCN Red List Status
Endangered (EN) (A1abd); Date assessed: 25 June 2018
View the Source
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
View the Source
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