Southern right whale
Eubalaena australis
TAXONOMY
Eubalaena australis Desmoulins, 1822, Algoa Bay, South Africa.
OTHER COMMON NAMES
French: Baleine du Cap; German: Südkaper; Spanish: Ballena franca del sur.
PHYSICAL CHARACTERISTICS
Length 43–53 ft (13–16 m); weight 200,000 lb (90,000 kg). One of the stockiest of all whales. Flippers are broad and tend to be more fan-shaped than for most other cetaceans. No dorsal fin or ridge on the broad back. Flukes are very wide and smoothly tapered, with a smooth trailing edge and a deep notch. Largely black, but may have white patches on the belly or back. Some blue-black, light brown, and nearly white individuals have been noted. Callosities on the head are present, as for all right whales. Whale lice are common in creases and folds of the body. 200 to 270 baleen plates up to nearly 10 ft (3 m) long.
DISTRIBUTION
Circumpolar in temperate to subpolar Southern Hemisphere; South Africa, Namibia, southern Mozambique, Madagascar (formerly at least), southern Angola, western and southern Australia, New Zealand (formerly at least), Chile, Argentina, southern Brazil, around numerous oceanic islands such as Crozet, Kerguelen, Amsterdam, and St. Paul (France), Prince Edward (South Africa), Auckland and Campbell (New Zealand), Falkland, South Georgia, Tristan, and Gough (United Kingdom).
HABITAT
Very widely distributed from near-shore waters to pelagic zone, and from temperate waters south to Antarctic. Main determinant of offshore habitat appears to be availability of dense concentrations of zooplankton. Near-shore wintering grounds typically have a gently sloping sandy bottom, relatively sheltered. Avoidance of unwanted attention by male suitors may help explain female's choice of nursery.
BEHAVIOR
Migratory, moving south and offshore in summer, north and inshore in winter, with at least portions of population congregating in coastal calving areas. Generally occur in small groups with no obvious social structure apart from close affiliation between mothers and calves. Aggregations form in productive feeding areas and when numerous males attempt to mate with focal female. Breaching (leaping clear of surface) and lobtailing (slapping water with flukes) are common on wintering grounds. Behavior called "tail-sailing" observed off Patagonia, with flukes high above surface acting as a sail to propel whale horizontally. Playful and curious behavior toward buoys, tide gauges, and kelp fronds.
FEEDING ECOLOGY AND DIET
Zooplankton, mainly copepods and euphausiids, must be found in dense concentrations to allow right whales to feed efficiently. Whales surface skim-feeding on krill (Euphausia superba), which are relatively fast-swimming and adept at predator avoidance, can engage in high-speed bursts (8 knots) and create considerable turbulence.
REPRODUCTIVE BIOLOGY
Average age at first calving about nine years, some individuals giving birth at six, others not until 13 years old. Single calves are born at intervals of three years. Calving occurs over a period of about four months during austral winter. Calves closely associate with mothers for at least several months but are weaned by one year of age. Gestation assumed to last about 12 months.
CONSERVATION STATUS
Lower Risk/Conservation Dependent. Although severely depleted by commercial whaling throughout range, strong recoveries underway in some areas, notably southern Africa, Argentina, and Australia. Numbers there total approximately 7,000, with annual increase rates of 7–8%. In other areas such as New Zealand, Chile, and Madagascar, there is little or no evidence of recovery. An important factor limiting recovery was unreported and only recently disclosed: illegal killing of more than 3,200 southern right whales by Soviet factory ships between 1951 and 1970, a period during which the species was legally protected.
SIGNIFICANCE TO HUMANS
Like other right whales, hunted relentlessly for oil and baleen. For last 30 years, interest in whale-watching has grown rapidly in South Africa, Argentina, and Australia. Marine-protected areas exist in all three countries to protect winter concentrations of right whales and facilitate exploitation as objects of tourism and study.
