The Orca: Killer Whale

While whale-watching, you may be lucky enough to see any of a number of whale displays. Let us put it that way: There is no guarantee, but if youʼd like to see Orcas and other whales such as humpback whales & minks in their natural habitat, then this is the right tour for you. Orcas are extremely acrobatic dolphins for their size. They are inquisitive and often approach boats, apparently to get a better look at the humans on board. They are often seen breaching clear out of the water, lob-tailing, flipper slapping, logging and spy hopping. They may speed swim with their entire body leaving the water at each breath. Subsurface beaches of rounded stones can attract many Orcas, which seem to enjoy rubbing their bellies on the smooth rocks (known as rubbing beaches).

The Orca (Orcinus Orca) is also called Killer Whale. Although the Orca is a part of the dolphin family.

Studies on the North Pacific Coast indicate that there are three distinct forms of Orcas:

Resident

These are the most commonly seen of the three populations in the coastal waters of the northeast Pacific. The Resident Orca feeds primarily of fish and sometimes squid. They live in complex and cohesive family groups. Pods possess lifelong family bonds, often living in large matrilineal groups and vocalizing in highly variable and complex dialects. Female residents characteristically have a rounded dorsal fin tip that terminates in a sharp corner. They are known to visit the same areas consistently. The resident populations of BC are amongst the most intensely studied marine mammals ever. Researchers have identified and named over 300 killer whales over the past 30 years.

Transient

The diet of these killer whales consists almost exclusively of marine mammals. Unlike residents, transients may not always stay together as a family unit. Pods consist of smaller groups with less persistent family bonds and vocalizing in less variable and less complex dialects. Female transients are characterized by dorsal fins that are more triangular and pointed than those of residents. The gray or white area around the dorsal fin, known as the "saddle patch," often contains some black colouring in residents. However, the saddle patches of transients are solid and uniformly grey. Transients roam widely along the coast—some individuals have been sighted in Southern Alaska and later in California.

Offshore

These killer whales were discovered in 1988 when humpback whale researcher Jim Darling signalled to killer whale researchers Michael Bigg and Graeme Ellis that he saw killer whales in open water. These killer whales cruise the open oceans and are believed to feed primarily on schooling fish. However, because of the large presence of scarred and nicked dorsal fins resembling that of the mammal- hunting transients, the possibility that they eat mammals and sharks cannot be ruled out. They have mostly been encountered off the west coast of Vancouver Island.

Orca Saddle


Definitions of Social Structure

Resident societies can be organized into a series of social units, from small to large, on the basis of these genealogical relationships. The maternal relatedness of the whales diminishes as one goes from the smallest kind unit, a mother and her offspring, thru increasingly larger units, the matriline, the pod, ad the clan. The largest grouping, the community, is the only social grouping defined by travel patterns and not on genealogy or acoustics. The general features of each of these social levels are described below:

Matriline

A matriline is a group of closely related whales links by maternal descent. A typical matriline consists of an older female, or matriarch, and her male and female descendants. The matriarch's daughters may be of reproductive age and have young of their own.

Pod

A pod is a group of related matrilines that likely share a common maternal ancestor in the recent past. Matrilines within pods are thus more closely related to no another than to matrilinies in other pods. Pods in the resident population of BC and Washington were identified and named in the 1970ʼs, primarily on the basis of travelling patterns (link to travel pattern of whales map).

Clan

The clan is the next level of social structure above the pod. It is basically defined by the acoustic behaviour of pods. It is comprised of pods that have similar vocal dialects.

Community

The top level of social structure is the community, which is made up of pods that regularly associate with one another. There are two resident communities of coastal waters of BC:

The Northern Communities and the Southern Communities

Our northern resident whales range thru coastal waters from midpoint of Vancouver Island north to southeastern Alaska and around the Queen Charlotte Islands.

The northern resident community is comprised of three clans. A, G and R, with a total of 16 pods. In 1998 the most recent year with good census coverage, the community was made up of 216 whales. The community has grown by over 60% from an estimated since of 132 in 1975.

The A 1 Pod (A30 matriline) is the most commonly encountered matriline in the northern resident community. Mostly due to its preference for the Johnstone Strait region. It was present in over 60% of all resident killer whale encounters in this area since 1987.

Scientist have observed or received photos of northern residents at many different locations in their range, but in no area are they found as predictably as in Johnstone Strait. Sightings have been made throughout the narrow inside passages of the central and northern British Columbia coast. The range of northern residents includes many thousands of kilometres of inlets, channels, passes and straits, much of it very remote.


Did you know that Orcas have been known to eat land mammals? There are records of pods killing and eating Moose and Caribou that swim across narrow channels and river mouths in northern Canada and Alaska.


Travel Pattern of whales in Johnstone Strait Area

Whale travel patterns


Definitions used in the Orca World

The following are definitions of some of the terms used in killer whale research:

Breach

Occurs when a whale leaps out of the water, exposing two-thirds or more of its body.

Calf

A young-of-the-year, typically born in fall-winter.

Clan

One or more pods that share a related dialect pods within a clan have probably descended from a common ancestral group and therefore are probably more closely related to each other than to pods from other clans.

Community

Comprises all pods that travel together, pods from different communities have never been seen together.

Dialect

A unique set of discrete calls made by an individual whale and fellow pod members, dialects of most resident pods can be distinguished either by ear or with a sound analyzer.

Discrete Call

A type of communication vocalization that sounds the same each time it is produced, on average, resident pods produce about twelve different types of discrete calls.

Echolocation

The Process by which killer whales and other toothed cetaceans use vocalizations to obtain information about their surroundings, similar to SONAR, echolocation involves the production of rapid, high-frequency clicks that echo off objects in the whaleʼs path.

Eye Patch

The elliptically-shaped white patch located above and behind a whaleʼs eye.

Flukes

The horizontal projections from the tail of the killer whale.

Off Shore Killer Whales

A little know population of killer whales, found mostly in offshore waters off British Columbia, appear to travel in generally larger groups than residents or transients.

Resident Killer Whale

A form of killer whales that feeds preferentially on fish, especially salmon, and has a very stable social structure.

Saddle

The grey pigmented area at the posterior base of the dorsal fin.

Spyhop

A behaviour where a whale raises its head vertically above the water, then slips back below the surface, a spyhop seems to be a means of obtaining a view about the water.

Transient killer whales

A form of killer Whales that feeds preferentially on marine mammals and has a looser social structure than that of residents, transients also differ from residents in dorsal fin shape, group size, behaviour, and vocalizations.

Whale encounter

An occasion when one ore more identifiable individuals have been located.


Interpreting Orca Activities and Behaviours

The activities of resident Killer Whale groups fall into four categories:

  1. Foraging
    The most common activity of resident killer whales is foraging. This activity includes all occasions where the whales are feeding or appear to be searching for food. Members of pods spread out, often over areas of several square kilometres, with individuals or small subgroups diving and surfacing independently while swimming generally in the same direction.
  2. Traveling
    A group of Orcas is considered to be traveling when it is swimming consistently in one direction at a moderate to fast pace, tight formation, and there is no sign of feeding. Whales travel from 5 knots or more.
  3. Resting
    The whale group usually rests tightly together abreast, forming a line of animals that dives and surfaces as a cohesive unit. If may whales are present, they group according to the appropriate matriline or pod with the matriarch (mother) in the centre.
  4. Socializing
    Socializing is a great variety of interactions and displays among Orcas. An entire group of Orcas can be involved. Breaching, spy hopping, tail slapping, and pectoral slapping are examples of there activities. Orcas often chase one another, or roll and thrash together at the surface.

Female or Male Orca

The Orca is unmistakable! Its body is black, his underside and lower jaw are white and there is a white patch behind his eyes and on its sides. The flippers are paddle-shaped, and its dorsal fin is tall and has a triangle shape. Differences in the appearance of the dorsal fin and saddle patch are used to recognize individuals. An identification photo of the female A 51 is shown here, along with the features that make her distinctive.
Reproductive organs of whalesOlder males can have can have fins as tall as 6 ft (1.80m).

Females have smaller and a more curved dorsal fin.

Male Orcas are much larger then female Orcas.

You can also identify an Orca close by, by listening to a loud, low, bushy blow.

Dorsal of Male and Female Orca whales