Killer whale; A Whale or a Dolphin?

By Melissa Hobson via National Geographic Published December 11, 2025

Many people still pretty confused about which family this big marine mammals belongs to; whales or dolphins? Well, this article can show you the truth about Orca!

Orca Species

Killer whales, which are also known as Orca (Orcinus orca), is one of the biggest and largest animals that belongs to the Delphinidae family, or dolphins. This family also covers others large animal such long-finned pilot whales and short-finned pilot whales that also have famous names ‘whale’ instead of ‘dolphin’.

Credit: NOAA Fisheries

Appearance

Orca is covered in mostly black on top and sides of their bodies also white patches or strikes near their eyes and under their bodies. Most people also mistook their white patches as their eyes when its literally not! Their eyes is well hidden in the black skin, just pair of small black eyes. An adult male Orca usually reaching 6 meters up to 8 meters and can weight over 6 tons, while for the females orcas can reaching 5 meters up to 7 meters and weight between 5 to 7 tons.

Based on the National Geographic, if we ever compared an Orca to a vehicle, it can reach the size of the America yellow school bus! Wow, how cool is that?! Another fun fact and cool thing about an Orca is that the average life span in the wild environment, aka left alone in the sea and not in the captivity or sea world, is 50 until 80 years! It’s almost same as average human lifespan!

Behavior and Diet

Orca is on the top of food chains in the sea, they have a very diverse diets, they eat fish, penguins, other marine mammals such as sea lions, seals, and even whales! They are very dangerous predator in the sea, with their teeth that can grow up to 4 inches they can tear through any animals skin.

Orca is a high social animals, they live in their groups or rather called ‘pods’ that typically consist of a few to 20 or more animals, and larger groups sometimes form for temporary social interactions, mating, or seasonal concentrations of prey. Each pods have different sounds to communicate that can only be understood by the individual in the pods. All pods use effective, cooperative hunting techniques that some liken to the behavior of wolf packs.

Reproduction

Females Orcas reach sexual maturity when they are 10 to 13 years old. The mothers going to give birth a single calf after 17 months pregnancy and nurse exclusively up to 2 years. While their birth rate is not well understood, orcas usually can have baby every three or ten years. After getting nursed for 2 years the juvenile, or the young orca, usually left their original pods and start their own adventures but in some cases the young orca is bounded to their original pods aka the pods they were born into its entire life!

So yeah, despite having ‘whale’ as their name, it turns out Orca or Killer Whales are actually part of the dolphin family! They are also well known to be one of the apex predator of the sea that live and hunt with their pods. That is all information that I can write in this article, I hope this article can clear the misunderstanding about the famous Killer Whales or Orca!