Balaenoptera acutorostrata, Lacépède, 1804
Identification
The Minke whale is the smallest and most abundant of the rorquals. The head is one of the most distinctive features. When looking at the head from above, the single, sharp and longitudinal edge along the center and the overall triangular shape are visible. The rostrum is narrow and pointed. The double blowhole is typical of all balleen whales. The blow is fast and reaches 2-3 meters in height, but rarely visible. They have 230-360 short baleen plates on each side of the mouth, with a white or cream color. The dorsal fin is sickle-shaped and appears on the surface, simultaneously with the blowhole. Despite arching the body before a dive, the flukes are not visible. The body is black or dark gray on the back, with a gray “V” pattern on the back behind the head. The pointed flippers have a white band that can be variable. The lower part of the body is white, gray or brown. They have 50-70 ventral grooves on the neck that end just behind flippers.
Biology
The gestation period is 10-11 months and the calf is born with 350 kg and 2.4-2.8m. Adults can weigh between 5 and 10 tonnes and measure between 7-10m in length, with females slightly larger than males. Minke whales feed on krill and on a variety of small pelagic fish such as herring, capelin and sandlance
Apparently it is observed all over the world, but it is less common in the tropics than in cold waters. Longevity is unknown, but it is likely to be around 50 years old.
Behavior
Some animals are curious and approach the boats, but it is difficult to approach them by boat. The minke whale don´t “wake-ride”, but it can swim next to a boat for a considerable distance. Sometimes spyhops and breaches. The typical dive sequence is between 5 and 8 blows at intervals of less than a minute, followed by a long dive that lasts between 3 to 8 minutes. Can remain under water for as long as 20 minutes. Sometimes can be seen feeding near the surface bdeneath a flock of feeding seabirds. Individuals are mainly found alone or in small groups (1-3).