The southern right whale is a large baleen whale with a less streamlined shape than balaenopterids like the humpback whale (Megaptera novaeangliae). They grow to a maximum length of 17.5 m and weight of 80 t, with mature females often slightly larger than males (Bannister et al. 1996). The mean length of sexually mature females off the South African coast was calculated as 13.85 m (Best & Ruther 1992) and off Argentina as 13.66 m (Whitehead & Payne 1981). Mature females in Soviet catches from the Southern Ocean averaged 14.34 m (Tormosov et al. 1998). Southern Right Whales are about 5.5 m long and 1000-1500 kg at birth and physical maturity is reached at a length of 16 m (Bannister et al. 1996). Age at physical maturity is unknown (Bannister et al. 1996). The vast majority of southern right whale individuals are uniformly black in colour, often with a white ventral blaze of varying size and shape centred on the umbilicus. About 2.8 % of adults are mottled dark brown to grey, having been white with varying degrees of black marking at birth (Bannister 1990). A small number of adults (1.4-3.4 %) have white dorsal blazing (Bannister 1990). The pectoral fins are short and paddle like, the flukes are uniform in colour with smooth trailing edges, and there is no dorsal fin. A distinctive feature is the presence of whitish or yellowish callosities on the rostrum, chin and lower jaw. These are formed as roughened patches of keratinised skin and colonised by cyamids (small crustaceans known as ‘whale lice’) (Cummings 1985a). Callosity patterns are present at birth and persist with minor variation through life, such that individual southern right whales can be identified by the number and configuration of callosities (Payne et al. 1983). They provide the basis for studies relying on an ability to recognise individuals from natural markings over long time frames (Best 1990e; Burnell & Bryden 1997; Payne 1986). The southern right whale head is large compared to body size and the jaw line strongly arched (Jefferson et al. 1993). Baleen plates number from 205-270 and the baleen is usually, dark, very fine, and long (maximum 2.2 m) in comparison to other species (Cummings 1985a). Blubber thickness has been recorded from Soviet catch data as 14-17 cm for a 10 m whale and 23-24 cm for a 15 m whale (Tormosov et al. 1998).
Southern Right Whale |
Government evidence of impact of climate change:
Australian Government Department of Agriculture, Water and the Environment, Species Profile and Threats Database, Eubalaena australis
Climate Variability and Change There is evidence that climate variability affects reproductive output in the species.
Changes to climate and oceanographic processes may also lead to decreased productivity and different patterns of prey distribution and availability.