After reducing their population by 90% due mostly to whaling, humpback whales came seriously close to extinction. It is with great joy and relief that we are starting to see these magnificent giants returning slowly but ever so surely to Johnstone Strait and vicinity. They are now listed only as threatened on the Species at Risk Act -SARA
Affectionally called “humpies”, these magnificent whales are easily identifiable as they dive “humping” their backs and gliding effortlessly by cruise ships and whale watching boats, putting on a show for the tourists. Their friendly and curious nature makes them very appealing to whale watchers, as they often will swim alongside boats to take a look a closer look. Their most easily recognizable traits are their tiny dorsal fin on their massive dark bodies and unique throat grooves that expand enabling them to maximize the quantity of water and food taken in one gulp.( pic)
Not a toothed whale, they are equipped with baleen, a very unusual feature that resembles thick strands of long hair that hangs down from their upper jaw and acts like a strainer enabling the whale to grab all the plankton, krill and small fish that is filtered through these strands. They eat about a ton of food each and every day during the feeding season, which lasts through the summer months, of which they spend in the cooler waters of Alaska and British Columbia. They migrate south to warmer waters in the winter (Baja and Hawaii) where they do not eat at all but survive off their blubber. Instead they focus all their attention on mating and giving birth.
Females reach sexual maturity at 4-6 years, males take a little longer. A typical gestation period is 11 – 12 months. Calves will stay close to their mother for one year, making the trip north and back again only once before they become independent. They typically live up to 50 years.
There are advantages and disadvantages to studying the humpback whale. The fact that they spend about 90% of their lives underwater and their long distance migrations can make it difficult. Fortunately, their migration routes are close to shore enabling researchers to photograph them and be able to identify individual whales by the shape and markings on their tails. (pic)
Perhaps the most interesting and unique feature of the humpback is their song. Only the males sing and only in breeding season therefore, it is thought that this may be a mating call. These songs can last up to 20 minutes with repetitions that go on for days and can be picked up by other humpbacks up 160 km away.
The most astonishing study in recent history is the discovery of a type of spindle neuron in the humpback’s brain, only thought to have existed in humans and great apes. This neuron is associated with cognition, self-awareness, judgement, etc. They have also been found in the brains of Orca, fin whales and sperm whales, suggesting high intelligence.
The biggest risks to the humpbacks that thrive in the North Pacific and Antarctic waters today are, believe it or not, whaling. Even though a worldwide moratorium was passed in the mid 1980’s on commercial whaling, Japanese whaling ships continue harvesting all types of whales, including humpbacks, on the fallacious argument that they are using them for scientific research purposes.They insist they need to kill the whales in order to study their stomach contents, age and other data and even go as far as stating absurdities such as blaming whales for the declining fish populations in the world’s oceans. To add insult to injury, the meat leftover from their kill is then packaged and sold to Japanese restaurants, schools and supermarkets.
Secondary threats to the humpbacks are acoustic disturbances, like military sonar (see below), pollution, entanglements in nets and fishing gear, and collisions with cruise ships and other large vessels.