Types of Killer Whale: Guide to Killer Whale Types
Killer whales (orca) ignite some debate when it comes to classification. There are known to be eleven different types of killer whale in our oceans, each with specific behaviours, language, physical differences, habitat and diet.
Many argue that these differences are indicative of not just animal subspecies, but also clearly defined species of killer whale. That these differences are, in fact, so large that orca are not just separate by type but species completely.
That debate still rages on, but until the scientific community can reach a consensus, killer whale ecotypes are what define their differences, not any sort of subspecies or class. The types of killer whale we know about are:
Northern Hemisphere Killer Whales
Resident Killer Whale
Resident killer whales are so-called because they have residential feeding patterns. They are only found in very distinct areas of the west coast of North America, including Alaska and Canada, and the east coast of Northern Asia, such as Russia and Japan. They stick to their local zones and have strong and closely-knit communities. They are exclusively fish-eating killer whales, which is likely due to the non-migratory pattern of their prey, allowing them to remain in certain areas without facing a lack of food. Resident orca as a smaller type of killer whale and display unique behaviours including specific social interactions and dialects, as well as young remaining with their mothers throughout their lives and not moving to other pods or groups.
Transient Killer Whale (Bigg’s)
Predominantly found between the Arctic and Baja California in Mexico, transient killer whales - otherwise known as Bigg’s Killer Whale - are migratory orca that move across vast ranges as they hunt large mammal prey. They live in small and close communities. The small community aspect ensures enough food upon a kill, which is harder to come by than the fish populations fed on by resident killer whales, which they often share waters with. Communities have specialisations, some Bigg’s killer whales hunt whales while others sea lions. Transient orca are one of the largest killer whale types, which is typical of mammal-eating killer whales.
Offshore Killer Whale
The offshore killer whale is the most elusive type of orca in the northern hemisphere. This is simply because they hunt in the open ocean away from inhabited shorelines and are therefore difficult to spot and observe. Offshore killer whales are found off the coast of California and range all the way to Russia. As is commonly observed in open ocean predators, offshore killer whale hunt in pods of around 50 animals, the largest communities of orca for any ecotype. This allows them to rely on others to help find food in such a vast hunting ground. It is unknown what exactly offshore killer whales feed on, although it is suspected that sharks make up the majority of their diet due to the wear seen on the teeth of offshore orca, thought to be caused by the rough skin of a shark. Offshore orca have been seen sharing food with older animals who likely cannot make kills due to damaged teeth from a life of shark hunting. It is also thought they kill fish. Offshore orca are the smallest killer whale in the northern hemisphere, which supports their large pod society and expansive food range, as they’re able to share and go longer without meals.
Northern Atlantic Type 1
The Northern Atlantic Type 1 is a small-sized killer whale that predominantly inhabits the regions of Iceland, Norway and Scotland. They are less specialised than other orcas, and will eat some small mammals like seals, although they are more commonly observed hunting herring and mackerel in the Norwegian Fjords. These are one of the only types of killer whales you can swim with. These killer whales have developed a very distinctive hunting pattern whereby they stun fish using their flukes by swiping at them aggressively after corralling them into ‘bait balls’. Type 1 Killer Whales live in tightly connect pod communities, and it is thought they may be developing separate characteristics and hunting patterns within these groups, which may potentially lead to the Type 1 Atlantic Killer Whale separating into even more refined types in future.
Northern Atlantic Type 2
Northern Atlantic Type 2 killer whales are found off the coasts of Norway and Iceland, although they’ve also been seen as far south as the Azores. Type 2 hunt large mammal prey such as dolphins and whales, which leads them to source their food from a wider range than Type 1, which can rely heavily on coastal fisheries and spawning grounds. Being feeders of larger prey, they themselves are large types of killer whale, one of the largest found. They’ve got keenly sharp teeth for shredding flesh off prey, and exhibit distinctive slopping eye patches.
Other Northern Hemisphere Types
Orca are found in all waters around the northern hemisphere, with distinct populations observed off the coast of eastern Canada as well as in the Strait of Gibraltar. These may be part of the current North Atlantic ecotypes, or they may be separate types of killer whale. Research is ongoing. There are also sightings of orca around Hawaii, potentially offshore killer whales or perhaps a new ecotype. Then there are the ‘tropical killer whales’ seen in the Gulf of Mexico and around the Caribbean Sea. These may be ranging Type 1 North Atlantic killer whales or they may be their own ecotype.
Southern Hemisphere
Type A Killer Whale
Type A killer whales are the largest type of killer whale, known to reach up to nearly 10m in length. Their size comes from their diet of large prey, often minke whales which they follow through the Antarctic waters and further north into other regions of the Southern Hemisphere. It is thought, but not confirmed, that these are also the type of killer whales that hunt seals off the coast of Argentina in the famous scenes often witnessed in nature documentaries when orca beach themselves on purpose to feed on baby sea lions.
Type B Killer Whale
Originally thought to be the same type of killer whale, Type B has now been split into two separate ecotypes, large and small. Both were thought to initially be part of the same type because they have the same yellowish tinge to their light grey skin, thought to be acquired through swimming in algae-rich waters. They also hunt in the same regions, which are the ice flows off the coast of Antarctica:
Type B Killer Whale (Large) - Feeding on mammals like seals, large Type B killer whales are distinct in their well-known hunting pattern, which involves creating artificial waves to break apart ice flows on which prey are resting. This has earned them the name of Pack Ice killer whales.
Type B Killer Whale (Small) - Also called Gerlache orcas, these smaller Type B killer whales feed on smaller prey, which is known to include penguins and fish, although their exact diet is not completely understood.
Type C Killer Whale (Ross Sea Killer Whale)
The small type of killer whales, Type C Killer Whales measure up to 6m. Also known as Ross Sea killer whales, they’re paler than most killer whales and have the same yellowish tint to the skin as Type B killer whales. Unsurprisingly, they’re often found around the Ross Sea, which is a bay in Antarctica. They have particularly striking eye patches, which are narrow and sharply pointed. They are thought to specialise on Antarctic toothfish, which are very common in the Ross Sea.
Type D Killer Whale
These are the rarest kind of killer whales known to man, with their ecotype only proven through a handful of sightings and a mass stranding that occurred in New Zealand in 1955. We know very little about Type D killer whales. What we do know is that they feed on Patagonian toothfish and have the most distinctive body shape of all orca. They've got short dorsal fins, a rounded face and very small eye patches. It was initially thought they were a mutation of the killer whale species, but studies on the stranded orca of the 1950s and those few that have turned up since show us they’re actually a different ecotype and not a mutated species.
Other Southern Hemisphere Killer Whale Types (New Zealand Killer Whale)
Not often categorised a separate type of orca to those that hunt around the antarctic and south American regions, the New Zealand killer whale deserves its own place amongst the orca. A resident population of the island, this particular type of killer whale exhibits unusual behaviour for an orca, in that it appears to be a generalised hunter, eating everything from rays and sharks to seals and fish. A small but definite subsection of the killer whale population, New Zealand killer whales are a very unusual type of killer whale. Killer whales in New Zealand tend to intermingle heavily with killer whales often moving from pod to pod freely.
Image Credits: https://swfsc.noaa.gov/
