Whale Watching Guide
Distribution
Orcinus orca (killer whale) is the most widely distributed sea mammal on the planet. Populations of orcas occur in tropical, temperate and polar waters both north and south of the equator. British Columbia is fortunate to be home to the highest concentrations of orcas in the world. Orca do not wander the globe randomly, through each area has its own distinct population of these whales. Within BC, three distinct populations of orcas can be found - offshores, transients and residents. This high concentration of orcas is the reason why BC offers the most spectacular whale watching experience in the world!
The most commonly observed populations of orcas in BC are the resident whales. These resident orcas occur in two distinct communities - the northern residents and the southern residents. The northern resident whales consist of approximately 200 whales in 16 different pods. These whales range from southern Alaska to approximately halfway down Vancouver Island. The southern resident orcas are typically found around the water of southern Vancouver Island and Puget Sound. This community has 90 whales in three pods. These three social units are known as J, K, L-Pods. These southern residents are the whales that our tours focus on.
Life Facts
- Orcas are not a true whale, but the largest member of the dolphin family
- They may reach a maximum length of 10 meters (30 feet) and weigh as much as 12 tonnes
- Males average around 7m (23 feet) and 8-10 tonnes, females 6m (20 feet) and 4 tonnes
- Mature males may have a dorsal fin that can reach 2m (6 feet) tall
- The average male life span is about 30 years, although they may reach over 40 years
- Females average around 50 years and have been known to attain 90 years of age
Social Structure
Resident orcas spend the majority of their life in the presence of their
mother who plays the dominant role in the orca's life. The close-knit family
groups consisting of mother and offspring are called matrilineal groups and
comprise the smallest grouping of these whales. Then several matrilineal
groups usually travel together they are referred to as a subpod. A pod
consists of more than one subpod which prefer to travel together, but may
separate for extended periods. Clans are comprised of pods who share
similar vocalizations which reflects the level of relatedness to an original
single pod. The largest social structure component is a community. Pods
within a clan have been observed traveling together at one time or another.
Feeding
Populations of orcas around the world specialize on certain prey. In BC, the three different populations of orcas have quite different diets.
- Transient orcas feed exclusively on mammals such as seals, sea lions, porpoises, dolphins and other whales. However, attacks on moose and deer in, or near, the water have been recorded. Transients rely upon surprise and group strategies in many attacks to reduce the chance of personal injury.
- Offshores feed upon ocean schooling fish, squid and sharks. The large numbers found in offshore pods suggest group strategies to concentrate prey, however little is known about shi population of orcas.
- Resident orcas feed exclusively upon fish. Salmon make up over 90% of their diet, but bottom fish and other larger schooling fish may be preyed upon. Like the offshores, large number of whales aid in corralling fish into concentrated schools to make feeding easier.
Behaviour
The behaviour of orcas can be broken down into four groups:
- Foraging occurs when orcas are searching for food. Moving slowly, groups may be spread over several square kilometers with individuals using echolocation (sonar) to find food.
- Traveling can be identified when orcas group together and travel at a medium speed. Diving is fairly regular and predictable with a few short breaths and shallow dives followed by a longer dive.
- Resting groups of orcas can be easily spotted. Groups form a fairly straight line and swim parallel to each other in close formation. Orcas do not stop moving to sleep, but enter a semi-conscious state with regular dives and very slow swimming.
- Socializing occurs at anytime but is especially pronounced after the orcas have finished feeding and have extra energy. Underwater vocalizations are abundant and there is much interaction between individuals.
Although orcas spend over 90% of their time underwater, there are several exciting behaviours which can be observed on the surface.
- Porpoising - orcas can reach speed of 60 km/hr (36 mph) for short periods of time. When swimming quickly 2/3 of their body may come out of the water when breathing.
- Tail Slapping - repeatedly slapping the flukes on the sea surface may show agitation or be used as a form of communication.
- Spyhopping - orcas have fairly good vision out of the water and individuals may raise the first 1/3 of their body out of the water to view landmarks or boats in the area.
- Breaching - the most spectacular of behaviours, breaching occurs when an individual leaps out of the water and returns to the sea veiled in a huge explosion of water.
Identification
Orcas can be identified individually by observing the saddle patch. This
grey-white marking immediately behind the dorsal fin has markings unique to
each animal. Some may be quite distinct and others very similar so a sharp
eye is required to successfully identify individuals. Any unique scars or
markings on the dorsal fins may aid in identification.
Local Individuals
Identified orcas are named based upon their pod and the order in which they were identified. Researchers have also given many whales a common name because these animals are known well enough to be more than just a number.
