This past week, there has been a pod hunting and playing in the waters near Maple Bay on Vancouver Island. It is wonderful and a wee bit unusual to see them so long in the same hunting grounds. This partially due to their normal hunting behaviour but definitely impacted by the relentless roar of the motors of whale-watching boats.
In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, orca are known as max̱'inux̱. I do not know the word for orca in the language of the Quw'utsun Cowichan First Nation whose shores they are swimming near this week.
Up close, their colouring is equally lovely. When I was little, a few resident orcas would come up to our float house and rub up against the side to give themselves a good scritch. We used to offer to help them with this by lowering a deck broom and rubbing it along them. They would roll around playfully and seemed to enjoy it much the same way dogs and cats appreciate a good scratch.
They show curiosity and intelligence when they look at you and understand that your intention was to help not hurt when the broom was offered. One of them did give the broom a gentle nibble and carried it off a ways but very politely returned it a few minutes later.Across their back and along their pectoral flippers is a nice glossy black, The exception is their saddle, a wee patch of greyish white just behind their dorsal fin.
Whales breathe through their nostril or blowhole that sits in the centre of their forehead. The blow of mist you see in the photo above is this fellow breathing and pushing air out through his blowhole and some seawater along with it.
Killer whales have a white patch under their heads (lower jaw), under each fluke and a patch along their rear edge as you move towards the tail. While these patches of white make them easier for us to see and identify them, they act as camouflage to those they are hunting in the water.
Their large bodies are streamlined (hydrodynamic), like a submarine, for moving through the water. Whales have flukes or a tail used for swimming. The flukes are moved in an up-and-down motion to accelerate. The dorsal fin acts like the keel of a boat; it keeps the whale from rolling side to side while swimming. They have pectoral flippers just behind the head. These pectoral flippers are used for steering, turning, and stopping.
Live in coastal and offshore waters; resident pods may frequent localized waterways (bays, sounds, etc.) whereas transient pods tend to cover more extensive, varied areas.
An extended clan of orcas, known as the Southern Resident Orca community, socialize and forage in the inland waters of Washington State and British Columbia. The population grows and lessens in relation to the overall Chinook salmon abundance. It may have been this pod that were playing off our shores this week. They are certainly in the neighborhood on and off.
Females (cows) reach reproductive maturity quite late in life at around 14 to 15 years. They give birth every three to ten years, following a 17-month pregnancy. In our local waters, these young join the pod and stay together their whole lives.At birth, the 2.6 m long calves arrive able to swim and dive and grow quickly feasting on their mothers' milk for the first year of their lives.
The newborns stay close to mamma, feeding and learning from her and from the close-knit members of the pod. Over the course of their lives, these newborns will grow from 120 to 160 kg up to 3,600 to 7,250 kg.
Like all dolphins, orcas use sophisticated biological sonar, called echolocation. Echolocation enables them to locate and discriminate objects underwater. The vocalizations within whale communities vary and each are different from those in other communities. The calls also bring the pods together over large areas of water when it is not possible for the whales to see each other.
When all goes well, orcas live to be a ripe old age. Some males have been known to live into their 40s and perhaps up to 60+ years old. Females have been known to live up to 90+ years old.
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