The Orca is counter shaded: black on the top and mostly white on the bottom. Looking down from above, the black on the dorsal side mixes with the dark ocean. Looking up from below, the white on the ventral side blends into the sunlit water. Male Orcas have the largest dorsal fin of any marine mammal. It can get up to 6 feet tall.
The dorsal fin acts like a keel, and each dorsal fin is unique for each Orca. The peduncle is the large muscular area between the dorsal fin and the flukes. The caudal peduncle is the part where the flukes meet the body.
They can easily breathe through the blowhole without lifting their entire head out of the water. Females give birth every three to ten years, following a month pregnancy. Young are able to swim and dive at birth, and they grow quickly on their mothers' milk. Calves are weaned after 12 months. Newborn calves are feet long and weigh kg lb. Did you know? Whales are warm-blooded like other mammals.
A fatty tissue called "blubber" keeps them warm. Echolocation enables them to locate and discriminate objects. Orcas live in small, close-knit, groups called pods. Males usually live into their 40s and females into their 60s. Orcas have no predators. Orcas have even learned the dangerous trick of beaching themselves to catch sea lions in Patagonia before wriggling back into the water. Orcas behave very differently in captivity, and orca attacks on humans have occurred in zoos and aquariums.
A orca called Tilikum, kept at Sea World for 25 years, was involved in the deaths of three people on separate occasions. Cetaceans, including orcas, have the ability to rest one side of their brain at time. A group of orcas is known as a pod. Female orcas beyond breeding age will help to guide and care for young members of the pod. In the ocean orcas rely on using clicks and whistles to exchange information with the rest of the pod.
Female orcas have a significantly longer lifespan than males, despite the fact that they undergo menopause, so they can live for decades after they can no longer reproduce. In the wild, female orcas live for an average of 50 years, while the average for males is just 29 years. Bigg's killer whales, or transient orcas, can also be found in the North Pacific.
These orcas travel great distances and hunt mammals such as seals and whale calves. Offshore orcas can also be found in this region. They live far from coastlines and have been seen eating fish and sharks, but relatively little is known about them. Type 1 orcas are generalist eaters and have been observed eating fish and seals around European countries, including Norway and Scotland. Type 2 orcas are rarer and mainly eat other whales and dolphins.
Scientists didn't have sufficient data when it was last assessed in due to the uncertainty regarding its taxonomic classification — whether orcas should be split into different subspecies or species.
The IUCN noted that as a single species, the killer whale is abundant and widely distributed. However, they still face threats from human activities and some regional populations, such as the orcas dependent on bluefin tuna in the Strait of Gibraltar, have declined significantly.
Human civilizations around the world kill orcas directly and indirectly. They are still hunted for food in small numbers, or as a means to control their population, in Greenland, Japan, Indonesia and the Caribbean, according to the IUCN.
Contaminants in the ocean and seas, such as chemicals and oil, pose a threat to orcas along with disturbance by boats, overfishing and other disruptions to their food supply and climate change, according to IUCN. Killer whales are protected in the U.
Southern resident killer whales are also listed under the Endangered Species Act as they are at particular risk of extinction, due to threats like noise from boat traffic and a decline in the salmon population — their preferred food.
A SeaWorld orca named Tilikum was the focus of the popular documentary "Blackfish," which took a critical look at killer whales in captivity. Tilikum was involved in three human deaths, including that of SeaWorld trainer Dawn Brancheau in The documentary created a public backlash against SeaWorld, and in the marine park chain announced that it was ending its killer whale breeding program, Live Science previously reported. Tilikum died of a bacterial infection at SeaWorld in at the age of Another famous captive orca was Keiko, who played Willy in the film "Free Willy.
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