THE CYCLE OF LIFE
Humpback whale calves are born in warm waters such as the Caribbean Sea, usually in mid winter. At the time they're born, they are 2-4 metres in length and weigh 1-2 tons.
For the first year of its life, a calf will stay by its mother's side. The mother nurses the young whale and even though it's capable of surviving on solid food after only 6 months, the mother continues feeding it milk for up to year. The mother's milk contains lots of fat and as the calf suckles an amount equal to at least 10% of its own bodyweight daily, it might grow to 9 metres in length within that first year of its life.
The mother and calf start their migration towards the summer feeding grounds up north together, but eventually split up and go their own ways.
In some places, juvenile humpback whales have been observed hanging out together or in the same area. Depending on the population, they reach sexual maturity at an age of 6-12 years at which point they're usually around 12 metres in length.
Most adult humpback whales migrate annually between their feeding and breeding grounds.
Males will attract females by showing off their strength as they breach, slap their tails and flippers or even fight each other. Along that, they're known to sing really unique songs which may last for hours. Normally, whales belonging to one population sing the same song repetively and changes occur only slowly over time. The singing itself might last for hours.
Females don't mate or give birth annually, but every other or third year normally. After a gestation time of about 11 to 11.5 months, the baby humpback whale is born.
- Sarah