Have You Seen Any of These?

Tuesday, March 16, 2010

Killer Whales (Orcinius Orca) of BC


The Killer Whale, (Orcinius Orca), is probably the most widely known species of whale and the most seen by tourists during whale watching excursions and boaters. More commonly referred to as Orca and occasionally as Blackfish, these whales are even seen while traveling on BC Ferries. It is the most watched, monitored and researched of any species of whale or dolphin in BC. It is also the most recognizable with it's tall dorsal fin and easiest to spot as they surface in the wild since they tend to travel in groups known as pods.

Pods are actually their own matriarchal family groups. Animals born into a pod, stay in the pod their entire lives. This is like living with your mother, aunts, uncles, cousins and brothers and sisters all descendant from your mother's side of the family for your whole life. It is extremely rare for an Orca from one pod to be accepted or join with another pod of whales. The gene pool gets mixed up by not having any father within the same pod. Each pod has their own 'dialect' of communication through various squeaks, burbles, and whistles. (Check back for sound clips as this blog progresses).

The term “Whale” is a misnomer since the Orca is actually from the dolphin family. We associate “whale” with something very large and they are much larger than the majority of dolphins. They are a whale of a dolphin.

Killer Whales have a varied diet, although some might specialize in a particular type of meal. There are three distinct types of Killer Whales in BC. Resident Orca are exclusively fish eaters. Consider them the vegetarians of the Killer Whale family. Transient Orca are meat eaters and are frequently seen preying on seal, sea lions, dolphins, porpoises and even larger whales. Transient whales are thought to eat the occasional fish. Then there are the Offshore Orca. It is unclear if they have a food specialty and may actually feed on both mammals and fish. I have seen them feeding on fish and harassing larger whales, but never actually taking a mammal.

As the names for these types of Orca imply, these whales have known areas of travel. In and along the BC coast, the most frequently and consistently seen are the Resident Killer Whales. Of the Residents, there are two distinct populations. In the inside waters, the Northern Resident Orca spend their time traveling throughout the Northern part of BC from around the Nanaimo area in the South to as far North as Alaska. The Southern Residents travel from around the Comox area in the North to parts of the Washington coastline in the South. As you can see, the Northern and Southern Resident Killer Whales have only a small area of overlap in the inside waters of our coast. None of the different types of Killer Whales tend to associate with one another.

Transient Orca seem to come and go. As their name implies, they are transient whales and just pass through. It is unclear as to their actual territory, if they even have one. These whales have been seen coming into the inside Strait of Georgia from the top end of Vancouver Island by Cape Scott and leaving at the bottom end by Victoria. Perhaps they circumnavigate Vancouver Island as well as meander back up or down our inside passages. They are routinely seen in the inside waters of BC.

Offshore Orca very seldom travel into the lower inside waters of British Columbia at all. These whales spend most of their time in off shore waters of the open Pacific Ocean, or at least mostly in the open waters of BC's West coast. They are regularly seen in the inside passage of BC's North coast for short periods of time and occasionally in the Blackfish Sound area at the top end of Johnstone Strait.

These Orca or Killer Whales have no known natural predators. In years past, they were shot and slaughtered thinking that they were “Killers” of everything in their path. We now know that these highly intelligent whales are closer to us than we might like to think. They are organized, look at the Transients whales on their coordinated hunts, they are protective of their family, look at reports of Offshore whales attacking boats that have inadvertently hit one of their pod, and they are social, look at their family ties and Resident whales mixing it up with other pods in a “Super Pod” party.

Killer Whale (Orcinius Orca) Specifics:
Length:
      Males: up to 10 m (33 ft)
      Females: up to 8.5 m (8 ft)
Weight:
      Males: up to 10,000 kg (22,000 lbs)
      Females: up to 7,500 kg (16,500 lbs)
Colour:
      Black body with white underside
      Oval white eyepatch
      Grey to white saddle patch behind dorsal fin
Features:
      Roundish head with slightly pointed beak (nose)
      Paddle shaped pectoral fins
      Prominent dorsal fin located midpoint of back
      Adult male: dorsal fin taller (around 2 m or 6 ft) than female and straighter
      Females and juveniles: dorsal fin usually less than 1 m (3 ft) and curved