A weekly feature named ‘The Hunter’s High Road.’ Each Tuesday check back to see an animal that represents the apex of predatory evolution. Carnivores come in a range of shapes and sizes, using a variety of tricks to catch their prey. Some are powerful, some are beautiful. All are deadly.
This week I turn my attention towards Orcas, the largest of the dolphin species and arguably the most efficient hunter of the seas. These massive creatures can be found through the world in Polar Regions to the Equator. They reach up to 9 metres and hunt together in family pods of up to 40 individuals. Their diets range from seals, sea lions, squid, fish and whales.
What makes them such incredible hunters is their tactics and adaption based on region. Orcas in resident pods don’t hunt the same way as transient Orcas. Resident Orcas tend to prefer fish while transient Orcas go after marine mammals.
Orcas that hunt in the Arctic will rear up onto ice sheets to grab seals. If a large whale is being hunted the animals will attack from several angles, tiring adults out or drowning calves. This behaviour is reminiscent of wolf packs, earning Orcas their ‘killer whale’ reputation.
Antarctic Orcas eat about 67% fish, 27% marine mammals and 6% squid. Alaskan Orcas eat 65% fish, 20% squid and 15% marine mammals. Adult Orcas will eat 3% to 4% of their body weight per day. Fully weaned calves eat up to 10% of their body weight. Mating season peaks in October to November in the Western North Pacific. Calves are born in the water, tail-first and nursed close to the surface. The mother’s milk is rich enough for the calf to rapidly develop an insulated layer of blubber.
Orcas aren’t known to be a critically endangered species. It is more dependent on region and type. Orcas in the Pacific Northwest are under threat from a salmon depletion brought on by pollution. Seal and sea lions populations have declined on the west coast of Alaska.
Orcas in captivity are seen as attractions. Although it might seem entertaining to watch them perform, captive Orcas have drastically reduced life expectancies, some only reaching their 20s. The animals are known to live an average of 46 years in the wild.
The Whale and Dolphin Conservation Society has campaigned against this practice. The organisation was established in 1987 and is based in Chippenham in the UK. You can help by adopting an Orca for just £4 a month.
Orcas are intelligent, powerful predators who have adapted to their environments over millennia. Their speed, tactics and team work make them worthy of respect. We can show our respect by making sure they’re protected and be less inclined to see them as captives for our amusement.