Killer Whales
Killer whales were, until very recently, possibly one of the most maligned marine mammals. Although they are the only cetacean (dolphin and whale) to live on warm-blooded animals, stories about their voracious appetites and treacherous natures have been disproved, thanks to the studies and observations of seagoing scientists and others. Numerous films have been made about their biology in the wild and there have been floods of popular articles written about them which have all helped to dispel old myths and make them better known than perhaps any other cetacean species.

There is no recorded instance anywhere in the world of unprovoked attacks on human beings by killer whales.

DESCRIPTION
Killer whales have distinctive black, white and gray markings. Males grow to about 9,1 metres (30 feet) in length and females 7,9 metres (26 feet). Mature males have a dorsal fin of over 1,7 metres (5,5 feet) in height which is easily recognisable from a fair distance away. The dorsal fin of females is about half the height of the males. Immature males have dorsal fins similar in size and shape to females. Flippers are almost twice as large in males and flukes are also considerably larger. Weight is around 7 200 kilograms (8 tons) in full grown animals. Most animals have a light-gray "saddle" marking just behind the dorsal fin. The shape of this "saddle" differs in individual whales and is a useful form of identification.

SOCIAL GROUPING
Among the types of social groupings found in cetaceans, the killer whale pod is unusual. There is now extensive evicence that the pod consists of the same individuals (males, females and juveniles) which travel together throughout the year and over a period of at least seven years. The group is cohesive and travels close together, or in contact, along a broad front seldom exceeding 1,2 kilometres. There is a high degree of co-operation when hunting and ample evidence of communal concern. Typical pod size ranges from single to about 50 animals, though larger aggregations have been noted, especially in Antarctic waters.

DISTRIBUTION
Distribution is world-wide, but they are more abundance in Arctic and Antarctic waters where there is a never failing supply of food. In some areas of the world killer whales appear to be migratory while in other they are apparently present all year round. This species has been sighted around the coasts of RSA, Namibia and Mozambique during all months of the year. Sightings have ranged from the surf zone to 600 kilometres out to sea. However, numbers do not appear to be prolific.

FOOD
Killer whales appear to be opportunistic feeders and diet may vary from one region to the next or within a specific area. They are primarily fish eaters, but also feed on cephalopods and prey upon other cetaceans, seals and seabirds. It is of interest that killer whales appear to be selective in their choice and timing of food intake. They do not prey upon a particular species just because it happens to be in the same vicinity as they are. Whales, dolphins, seals and seabirds have been observed associating with killer whales on numerous occasions but they were not molested or attacked and the prey species appeared unafraid of the killers.

BEHAVIOUR
Killer whales are "super cetaceans" and do almost everything faster and better than other whales and dolphins. They are capable of swimming at speeds of 50kph (27 knots) and can dive to a depth of over 300 metres ( 1 000 feet). They frequently "spyhop" (stand vertically with head and body, as far as the flippers, above the surface). This enables the whale to have a clear view of its surroundings. They "breach" (leap out of the water) and "loptail" (slap their flukes on the surface - a sound which carries for a considerable distance) and they navigate, herd their prey and communicate with each other by sophisticated sonar.

EXPLOITATION
International whaling statistics indicate that killer whales have been harvested world-wide (including RSA) but usually on a small scale. In the 1979/80 Antarctic whaling season the U.S.S.R. caught a total of 906 killer whales. Subsequent to this catch the International Whaling Commission banned factory ship whaling on this species. the average yield of oil per killer whale is 4,88 barrels per whale (1 barrel = 170 kgs) or 5,6 killer whales to 1 sperm whale. The meat is considered unfit for human consumption.

PROTECTION
A number of countries, including RSa, have legislation to protect dolphins and whales in their 200 nautical miles economic zone. However, little international legislation exists to protect small cetaceans and they remain vulnerable to predation by humans for food, incidental killing in the fishing industry, pollution and ocean dumping. Since the early 1960's it has become fashionable to keep killer whales in captivity for public entertainment and "education". DOLPHIN ACTION & PROTECTION GROUP is against this practice and has elicited the assurance from the South African Government that killer whales would not be imported into this country for live display.

Under THE SEA FISHERIES ACT 58 of 1973 no person shall without the written authority of the Director, kill, catch, attempt to kill or catch or disturb or be in possession of any dolphin or any part or product derived from a dolphin, also known as porpoise. Dolphins include all species of the superfamily DELPHINOIDEA. This protection operates within the 200 nautical miles Exclusive Fishing Zone (EFZ) of the Republic of South Africa.

We appeal to members of the public to co-operate in adhering to this legislation and to report any contraventions they may witness either to The Chief Directorate, Nature & Environmental Conservation, their nearest harbour master or police station or to THE DOLPHIN ACTION & PROTECTION GROUP. In this way we will ensure the continued existence of whales and dolphins around our coasts for many years to come.

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