There’s a reason why Orcas are called Killer Whales. But is this creature a whale or a dolphin?
Some sea creatures seen to jump right out of mythical tales because of their ferocity and size. One such mammal is the Orca (Orcinus orca), also called ‘Killer Whale.’
The question here is: Are orcas whales or dolphins? No. They are not whales. Yes they are dolphins. In fact, they are the largest of dolphins and the most powerful predators in the seas today. You can immediately recognize them by their distinctive black-and-white colored bodies.
They can weigh up to 6 tons with an average length of between 20 and 32 feet. Killer whales live for about 50 to 80 years.
Dolphins and whales both belong to the order Catacea, which include whales, dolphins, and also porpoises. However, when defining Catacea, the latter two are generally deemphasized. That’s why people generally mistake Orcas for whales.
Why the name ‘Killer Whales’?
Another reason most people assume Orcas are whales is because of the name killer whale. You must be wondering why these dolphins are so called. Well, they owe that name to sailors who observed groups of Orcas hunting whales and called them the ‘asesina ballenas,’ which is Spanish for assassin whale or whale killers. With time, that changed to killer whale.
Their scientific name is Latin, Orcinus Orca. Wonder what that means? It means ‘belonging to Orcus.’ Orcus is the Roman god of the dead or underworld.
Orcas are right at the peak of the food chain, even above the sharks. As a result, they have no natural higher predator. No wonder they kill for a living.
What do they eat?
They get their reputation because they will eat just about anything large enough that they meet in the water. Killer whales will snatch seals right off icebergs and eat them.
Typical to the dolphins, Orcas use echolocation to hunt down their prey and they hunt in groups called pods. Often, they are up to 40 individual killer whales in these groups.
You could almost liken their hunting behavior to that of a wolf pack. That is true of all dolphins, it is more like a typical hunting style.
Millions of years ago, different groups of killer whales started eating other things to avoid competition for the similar type of food. This led to the development of ecotypes. Orcas have very large brains compared to other mammals, pretty much explains the decision to eat different things in order to avoid competition.
Fun fact: they also have different ‘dialects.’ Each group has its own communication style that is different from another group. Members can distinguish the communication sound of their own group when they hear these sounds.
Growth and Breeding
Adult male Orcas can grow to about 30 feet long. On the other hand, the adult female killer whales grow up to 20/23 feet long. Their weight can be anywhere between 3 and 10 tons.
Threats to Orcas
Though there is no other mammal as powerful as the killer whale, these majestic creatures are not free from threats.
As you can expect, the major threat they face is from us, humans. Some common ways human activities are negatively affecting Orcas include:
- Oil spills
- Bio-contamination
- Competing for prey (industrial fisheries)
- Colliding with boats and ships
Another major threat is the practice of keeping them in captivity. Orcas often live up to a whopping 80 years. However, in captivity they tend to live only about 20 years.
Also, Orcas in captivity will attack humans more frequently and most of these attacks are fatal.
Due to the negative effects of captivity on these class of dolphins, some organizations are working to protect them. They include: WDC (supported by Mountaineers Foundation), Orca Conservancy, The Whaleman Foundation, etc.
Fortunately, these highly intelligent, trainable creatures have never been extensively hunted by humans.
References:
1. http://uk.whales.org/wdc-in-action/facts-about-orcas
2. http://www.nationalgeographic.com/animals/mammals/o/orca/
3. https://en.m.wikipedia.org/wiki/Killer_whale
Photo Credits:
1. https://commons.wikimedia.org/wiki/File:Killerwhales_jumping.jpg
2. https://commons.wikimedia.org/wiki/File:Killer_Whale_Tipe_B.jpg
