Fin whales are dark grey to brownish black dorsally, grading to pale or white along the abdomen. The undersides of the flippers and flukes are also white. The head is asymmetrical in colour and is mostly dark but the right lower jaw is white. Baleen plates are black on the left jaw and white on the right jaw. The body is free of mottling or extensive scarring. The fin whale is the second-largest whale species, after the blue whale (Balaenoptera musculus). Adult whales range between 20 and 27 m long and weigh more than 70 tonnes. As with other baleen whales, female fin whales grow to a larger size than males. The fin whale is very streamlined in appearance, with a distinct ridge along the back behind the dorsal fin. The dorsal fin is set two-thirds of the way along the back, and is up to 60 cm tall, curved and often slopes backwards. Fin whales are more gregarious than other baleen whales, and often occur in groups of 6–10, though single animals and pairs are more common. Aggregations of over 100 whales may be observed on feeding grounds. Recordings of regular, pulsed sounds, seemingly of mechanical origin, attracted considerable military interest in the 1950s, and eventually these sounds were conclusively linked to sightings of fin whales. Fin whale sounds are mostly 20 Hz or 22 Hz and are short, low-frequency tonal sequences. Pulsed sounds include a “rumble” which is a call of very long duration (about 30 seconds), in the frequency range of 10–30 Hz with extensive frequency and amplitude modulation. The association of these sounds with the reproductive season suggests that they may be used in reproductive displays by males.
Fin Whale |
Balaenoptera physalus
Status: Vulnerable on the EPBC Act list
Government evidence of impact of climate change:
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Australian Government Department of Agriculture, Water and the Environment, Species Profile and Threats Database, Balaenoptera physalus
Understanding impacts of climate variability and change Continue to meet Australia s international commitments to reduce greenhouse gas emissions and regulate the krill fishery in Antarctica.