In the Mediterranean Sea， orcas are considered “visitors“， likely from the North Atlantic， and sightings bee less frequent further east. However， a small year-round population exists in the Strait of Gibraltar， which numbered around 39 in 2011. Distinct populations may also exist off the west coast of tropical Africa， which have generalized diets.
The northwest Atlantic population is found year-round around Labrador and Newfoundland， while some individuals seasonally travel to the waters of the eastern Canadian Arctic when the ice has melted. Sightings of these whales have been documented as far south as Cape Cod and Long Island. This population is possibly continuous with orcas sighted off Greenland. Orcas are sighted year-round in the Caribbean Sea， and an estimated 267 (as of 2020) is documented in the northern Gulf of Mexico.
North Indian Ocean
Over 50 individual whales have been cataloged in the northern Indian Ocean， including two individuals that were sighted in the Persian Gulf in 2008 and off Sri Lanka in 2015.
Southern waters
Orca beaching to capture sea lion at Valdes Peninsula
A small population of orcas seasonally visits the northern point of the Valdes Peninsula on the east coast of Argentina and hunt for sea lions and elephant seals on the shore， temporary stranding themselves. Off South Africa， a distinctive “flat-tooth“ morphotype exists and preys on sharks. A pair of male orcas， Port and Starboard， have bee well known for hunting great whites and other sharks off the South African coast.
Orcas occur throughout the waters of Australia， New Zealand and Papua New Guinea. They are sighted year round in New Zealand waters， while off Australia， they are seasonally concentrated off the northwest， in the inshore waters of Ningaloo Reef， and the southwest， at the Bremer region. Genetic evidence shows that the orcas of New Zealand， and northwest and southwest Australia form three distinct populations. New Zealand orcas mainly prey on sharks and rays.
本小章还未完，请点击下一页继续阅读后面精彩内容！