Killer Whales have become extremely popular in the media lately due to the very public argument about whether or not they should be kept in captivity or not. This all started when the largest killer whale in captivity, Tilikum, killed a senior trainer at SeaWorld Orlando. Dawn Brancheau’s death started the argument leading to the film Blackfish and several high profile books about killer whales in captivity.
Killer whales (Orcninus orca) are the most widely distributed of all whales and dolphins as they are found in every ocean on the planet. This post is going to explore the lesser known things about the killer whale. For example, many people do not know that there is not just one type of killer whale. There are in fact 10 different ecotypes. These ecotypes have many different characteristics and are all genetically distinct from each other. Many scientists believe that the different ecotypes should actually be classed a subspecies, but this argument is still ongoing.
As I have mentioned the different ecotypes, I’m going to take this opportunity to write about the different ecotypes and what makes them different from each other. In the Northern Hemisphere there are 5 ecotypes. The first three of these can be found in the North Pacific.
The Resident Orca is a fish specialist which gets its name from its small home range. Residents live in the largest numbers within their pods and within the Residents there are two different communities; the Northern Residents and the Southern Residents. Both of these communities are genetically and acoustically distinct from each other. Because the Residents are fish specialists they are very vocal when hunting. Famous Resident: Lolita is the oldest captive killer whale who currently resides at Miami Seaquarium.
The next ecotype in the North Pacific are called Transient Orcas. Transients are mammal eating orcas and travel in much smaller groups than the Residents. Transients are named due to their large home ranges. Due to their diet of mammals Transients are much less vocal when hunting as mammals can also hear sounds on the same wavelength as the killer whales. Again Transient whales are genetically and acoustically distinct from the Residents. Famous Transient: Tilikum, the largest killer whale that ever lived in captivity, also the whale that killed trainer Dawn Brancheau.
The third ecotype in the North Pacific are the Offshore Orcas. Little is known about the Offshore orcas as they are far from sure and not often seen. However, when they are seen they are usually in large groups with more than 50 individuals. The teeth of Offshore orcas are worn down which suggest that they eat things with rough skin such as sharks. These mysterious orcas are the smallest of the three North Pacific ecotypes.
Moving onto the North Atlantic ecotypes of which there are two. The first of which is called the North Atlantic Type 1 orca. These small orcas live in closely related pods and eat both fish and mammals. These particular orcas are famous for their tail-slapping method of hunting where they herd fish into a tight ball and then slap the fish with their tails to stun them.
The second ecotype in the North Atlantic is the North Atlantic Type 2 orcas. These orcas prey primarily on whales and dolphins and they are a large orca with back-sloping eye patches.
The Southern Hemisphere also has 5 different ecotypes. The first of which is the Type A orcas. These are extremely large orcas thats can reach up to 31 feet long and hunt primarily Minke whales.
The Type B killer whales are split into two other ecotypes. There are Type B small orcas and Type B large orcas. The Type B large orcas are also known as Pack Ice orcas. These orcas forage for seals in the loose pack ice and are particularly famous for their co-operative wave washing hunting technique. The Type B small orcas are also known as Gerlache orcas. They are smaller than both the Pack Ice and Type A orcas and are thought to feed on penguins as they are most commonly found around penguin colonies. Both of the Type B orcas appear to have a brown or yellowish hue with a cape of paler colouring.
The fourth ecotype in the Southern Hemisphere is the Type C orca also known as the Ross Sea orca. These are the smallest ecotype of orca reaching a total length of 20 feet. These orcas normally appear grey and white as opposed to black and white and they sometimes have a yellowish hue. The cape of the Ross Sea orca tends to be darker than the rest of the body and they have a dramatically slanted eye patch. Little is known about the diet of the Ross Sea orcas, although it is believed that they eat Antarctic toothfish.
The final ecotype of killer whale is called the Type D orca. These are the subantarctic orcas and look dramatically different from the other ecotypes. These orcas are black and white in colouring and they have shorter dorsal fins, rounder heads and the smallest eye patches. Very little is known about these orcas as there have been very few sightings. It is believed that they feed on the Patagonian toothfish.
If you want to know more about killer whales there are plenty of websites online, and if you are interested in captive killer whales I suggest watching the film Blackfish and reading books such as Death at SeaWorld by David Kirkby and Beneath the Surface by John Hargrove.
I hope this post has informed you more about killer whales, if you’d like more information please leave me a comment, and I’ll answer to the best of my knowledge.