Sei whale Balaenoptera borealis Lesson, 1828

Sightings in Madeira

March to October

ID characteristics

Large, slender, dark body with paler undersides.
V-shaped head with a single, central, longitudinal ridge.
Tall dorsal fin with variable shape but commonly sickle-shaped
Flukes look small when compared to body size

Surface behaviour

Often swims close to surface with blow and dorsal fin visible simultaneously
When diving does not arch much its back and never shows flukes
Normally associated with large feeding frenzies of seabirds

Distribution

Worldwide, between parallels 65º North and 60º South.
Mainly in deep, temperate waters but can reach subarctic and subantarctic in summer.

Social

1 to 5 individuals together

Diet

Fish, squid, krill and crustaceans

Biometrics

Max length: 21 m
Adult weight: 20 to 30 ton

Blow

A narrow spray up to 3 meters high

IUCN Status:
Madeira frequency status:

Other languages common names

ENG - Coalfish Whale, Pollack Whale, Rudophi's Rorqual, Sardine Whale
GER - Seiwal
FRA - Baleinoptère de Rudolphi, Rorqual Boréal, Rorqual de Rudolphi, Rorqual de Sei
ESP - Ballena Sei, Rorcual Boreal, Rorcual de Rudolphi, Rorcual Norteno
SWE - Sejval
DAN - Sejhval
ITA - Balenottera boreale, Balaenoptera borealis
NED - Noordse vinvis
NOR - Seikval, Seihval
POL - Sejwal
POR - Baleia-sardinheira Baleia boreal, Baleia glacial ou Baleia-sei