British Columbian Killer Whale Population

Northern Residents

Southern Residents

Transients

Offshores

Diet

Fish.  Mostly salmon – with their favourite being Chinook. Some herring, squid, halibut, rockfish and flounder.

Marine mammals – mostly seals, harbour porpoise and Steller sea lions.  Possibly some birds. They do not eat other killer whales!

Believed to be fish.  Unlikely to eat salmon.  Diet may include halibut and shark species

Population estimate (2006)

235

85

220

250+

Sound production (vocalizations and echolocation)

Very vocal and make great use of echolocation to find prey.

Three different dialects (acoustic clans) in the population.

Very vocal and make great use of echolocation to find prey.

Only one dialect in the population.

Very quiet; hunt using stealth

Very vocal

Range where most often sighted

Regularly found above the middle of Vancouver Island to southern Alaska

Sighted very regularly around Johnstone Strait

Regularly found around the Southern end of Vancouver Island but also sighted in Washington and Alaska

Southeast Alaska to California

Most often far off the coastline

Social structure

Travel in matrilines where they stay with their mothers.  They avoid inbreeding through each matriline sounding different. Northern and southern residents do not mate with one another as they sound too different.

Matrilines are not as stable.  Combinations of matrilines traveling together can be very variable.

Travel in groups of 30+

Social structure unknown

Cultural behaviour

Rub themselves on black smooth stone beaches like those in the Michael Bigg Ecological Reserve at Robson Bight

Well studied?

Yes – resident orca have somewhat predictable behaviours since they follow salmon and because they travel in matrilines

More difficult to study because:

They are very quiet

They dive longer

Absence from the matriline does not mean they are dead 

More difficult to study since they are most often far off shore

Male killer whales

Female killer whales

Maximum size

9 m; 5,568 kg

7.7 m; 4,000 kg

How long they live - years

(Life expectancy)

Average = 30

Maximum = +/- 60

Average = 50

Maximum = +/- 80

Average age of puberty

13.5

Only then do the males grow much bigger dorsal fins; up to 1.8 m

14

Reproduction

Possible from puberty to death. Note that older males appear to be more often chosen by the females.

From puberty to around age 40

Note:  Only 1 calf born at a time.  On average, a female has a calf every 5 years.  Gestation is 17 months.