The Pygmy Right Whale is the smallest and least conspicuous baleen whale, resulting in it being one of the least known species. However, current research by Australian scientists is expanding the understanding of this species. The Pygmy Right Whale is the only right whale with a dorsal fin. This fin is falcate (sickle-shaped) and set about two-thirds of the way back from the snout tip. This species is atypical of right whales in other ways as well: it is rather slender, resembling more the streamlined rorquals in body shape, and its head accounts for less than one quarter of its body length. Although the Pygmy Right Whale has the arched jawline, with the upper jaw curving down towards the tip, of other right whales, the arch is not as pronounced as in other species. The flippers are small and slender with rounded tips. There are two shallow throat creases, reminiscent of those in Gray Whales. The colour of the body is dark grey above, ranging to white below. There is a dark eyepatch and an indistinct grey chevron across the back behind the blowhole. The flippers and tail flukes are dark grey above and paler below. The colour of the baleen plates is yellowish-white with a narrow, dark brown marginal band on the external edge that is diagnostic for the species and is the basis for its specific name (marginata: latin for “having a margin”). Pygmy Right Whales are 2 m at birth, and wean when they are 3.0–3.5 m. Most Pygmy Right Whales are physically mature at around 6 m, while maximum length and weight are 6.5 m and 3430 kg. Female Pygmy Right Whales are slightly longer than males. Less than 20 sightings of Pygmy Right Whales ‘at sea’ have been recorded, most of which have been of one or two animals, but some of up to 10 individuals. One sighting of 80 individuals was recorded in oceanic waters just south of the Subtropical Convergence.
Pygmy Right Whale |
Caperea marginata
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, Caperea marginata
Increasing ocean temperatures predicted by climate change scenarios could potentially decrease the extent of occurrence; with warmer water extending southwards along both coasts.