Species: Balaenoptera borealis

Sei Whale
Species
Mammals

A large dark gray baleen whale often with ovoid grayish-white scars; front edge of prominent dorsal fin is angled upward more than 40 degrees from the back; tip of snout is turned slightly downward; single ridge on rostrum; many longitudinal grooves on throat; flippers are pointed and relatively small; tail fluke is relatively small; slim and streamlined in dorsal view; with few exceptions, baleen is uniformly ash-black with fine white fringes; grows to 18.6 m in the northern hemisphere, 21 m in the southern hemisphere, with females reaching the largest sizes (largest males average a couple meters shorter than largest females) (Leatherwood and Reeves 1983).

Kingdom
Animalia
Phylum
Craniata
Class

Mammalia

Order

Cetacea

Family

Balaenopteridae

Genus

Balaenoptera

Natureserve Explorer
Source:
ELEMENT_GLOBAL.2.102708
Classification
Other Global Common Names
Rorcual del Norte, Ballena Boba - rorqual boréal
Informal Taxonomy
Animals, Vertebrates - Mammals - Whales and Dolphins
Formal Taxonomy
Animalia - Craniata - Mammalia - Cetacea - Balaenopteridae - Balaenoptera - , respectively).

A large dark gray baleen whale often with ovoid grayish-white scars; front edge of prominent dorsal fin is angled upward more than 40 degrees from the back; tip of snout is turned slightly downward; single ridge on rostrum; many longitudinal grooves on throat; flippers are pointed and relatively small; tail fluke is relatively small; slim and streamlined in dorsal view; with few exceptions, baleen is uniformly ash-black with fine white fringes; grows to 18.6 m in the northern hemisphere, 21 m in the southern hemisphere, with females reaching the largest sizes (largest males average a couple meters shorter than largest females) (Leatherwood and Reeves 1983).

Short General Description
A large baleen whale.
Habitat Type Description
Marine
Migration
false - false - true - Migrates between lower-latitude wintering grounds and higher-latitude feeding grounds. Movements in specific areas may be unpredictable (Leatherwood and Reeves 1983).
Non-migrant
false
Locally Migrant
false
Food Comments
Eats copepods, euphausiids, squid, and various small schooling fishes. May skim feed on copepods at surface or gulp feed on krill and small fishes (Leatherwood and Reeves 1983, Katona et al. 1983).
Reproduction Comments
Single calf is born usually in winter after a gestation period of about 11-12 months. Young nurse for about 5-9 months. Calving interval for individual adult females is 2-3 years. Sexually mature at an average age of 6-10 years.
Ecology Comments
Usually travels in groups of 2-5, may concentrate in larger numbers on feeding grounds.
Length
1860
Weight
2.0E7
NatureServe Global Status Rank
G3
Global Status Last Reviewed
1996-11-15
Global Status Last Changed
1996-11-15
Conservation Status Map
<img src="http://www.natureserve.org/explorer/servlet/GetMapGif?CA.BC=__&CA.LB=SNR&CA.NB=SU&CA.NF=SNR&CA.NS=SU&CA.PE=SU&US.AK=S3&US.CA=SNR&US.FL=SNR&US.GA=SNR&US.HI=SNR&US.ME=SNR&US.MD=__&US.MA=S1&US.NY=__&US.NC=__&US.OR=__&US.RI=__&US.SC=S1&US.VA=SNR&US.WA=__" alt="Conservation Status Map" style="width: 475px; height: auto;" />
Global Range
H - >2,500,000 square km (greater than 1,000,000 square miles) - H - Worldwide, but distribution and movements during much of year are poorly known. Coast of Mexico to Gulf of Alaska in the eastern North Pacific. Bering Sea to Japan and Korea in the western North Pacific. Gulf of Mexico to Davis Strait (especially off eastern Canada) in the western North Atlantic. Norway to Spain and northwestern Africa in the eastern North Atlantic. In Southern Hemisphere, Antarctic Ocean to coasts of Brazil, Chile, South Africa, and Australia. See IUCN (1991) for further details.
Global Range Code
H
Global Range Description
>2,500,000 square km (greater than 1,000,000 square miles)
ELEMENT_GLOBAL.2.102708