Minke Whale (Balaenoptera acutorostrata)
Suborder: Mysticeti Family: Balaenopteridae
Has been sighted in Hawaiian waters.
Other known names:
Pikehead, Little piked whale, Pike whale, Little finner, Sharp-headed finner, Lesser finback, Lesser rorqual
General description and habits:
International scientists, the International Whaling Commission (IWC) and the Convention on the International Trade in endangered Species (CITES) now recognizes two different minke whale species. The Northern Hemisphere Minke Whale (Balaenoptera acutorostrata) and the Southern Hemisphere Minke Whale (Balaenoptera bonaerensis). Minke whales are actually different species, further divided into discrete biological populations, each with a different conservation status. The Minke whale is not only the smallest rorqual; it is also the most abundant. Minke whales may have a black, dark brown, or gray back. All minkes have a long ridge on their head, and a tall dorsal fin far behind the center of their back. They have a double blowhole, a sharp pointed snout, and a straight mouth line. They do not have teeth, but have hundreds of baleen plates, which hang down 20 to 30 cm from their top jaws. These baleen plates act like a sieve, and catch fish and krill from the water. Minke whales have between 50 and 70 pleats running from their throat, and ending just past their flippers. These pleats stretch apart, to allow the whale to take in huge volumes of water to filter for food. Minke whales in the Northern Hemisphere have a white band on each flipper. Adults are usually between 7 and 10m long, females generally longer than males, newborns are between 2.4 and 2.8m. Their birth weight is about 350Kg (770 lb) and they weigh between 5 and 15 tons by the time they are grown. The Minke whale tends to be a solitary animal although in feeding grounds you can see them in pairs, sometimes eating beneath flocks of feeding seabirds. When feeding they seem to be oblivious to what is going on around them, concentrating on their food! They are unlikely to bow-ride but will swim beside a vessel for quite a distance. They are relatively fast swimmers with occasionally spy hopping and breaching. They can stay underwater for as long as 20 minutes.
Identity Keys to use in the field:
Streamlined body, Smooth skin with no callosities or barnacles, Sharply-pointed snout, Snout breaks surface first, Two blowholes, Throat grooves, White bands on flippers, Dark upper-side, Light under-side, Flukes rarely seen above the surface
Fish, Krill and/or other crustaceans
Minkes are found in oceans all over the world, though they are less common in tropical waters, because they prefer cooler temperatures. They are usually more concentrated in lower latitudes (closer to the equator) during the winter, and in higher latitudes (closer to the poles) during the summer, but migrations do vary. Other whales stay in the same area all year, and some individuals have their own home regions of water.
Hunting/Whaling, Habitat loss, Chemical pollution, Entanglement in fishing nets