Acrobatic and Powerful!
By Dagmar Reinhard
Using their massive flukes (tail fins), the humpbacks (Megaptera novaeangliae) propel themselves through the water. Regularly, they catapult their 40 tons of body weight completely out of the water, landing with a tremendous splash.
At an average speed of 14 km/per hour, they are capable of migrating the globe, from Antarctica to the Pacific. Their endurance is amazing; they travel over 5000 km during each migration with almost no rest along the way.
They eat up to 1.5 tons of food a day; they feed on krill, tiny shrimp like animals, and small fish. They don’t have teeth, but baleen plates that trap the food they swallow.
Humpbacks whales have developed the hunting bubble-net feeding method, rounding up highly concentrated masses of prey. The hunting members of a pod create a circle of 3 to 31 m across and about 15 m under the water. Then, the humpbacks blow bubbles in a spiral path as they swim to the surface.
The krill is trapped in the cylindrical wall of bubbles and moves up to the surface of the water in a giant, concentrated mass, going directly into their huge gobbling mouths.
Humpbacks migrate annually from southern or northern feeding grounds near the poles to warmer breeding waters closer to the Equator. When they migrate, they leave their main food source (krill) and have to survive for up to six months using their own fat storage (called blubber).
The size of an average humpback can be compared to that of a bus. The females are slightly bigger than the males and can reach up to 19 m in length.
In two different migrations a year, the humpbacks migrate to Costa Rica, either from the North Pacific Ocean or from the oceans of the Southern Hemisphere. They come to breed, give birth, and care for their newborn calves in the warm waters of the Southern Pacific.
Every 1-3 years a calf is born to a female.
If you go on a whale-watching trip, you might see the mother and calf playing while the bull is tail slapping.
Mothers and their young always swim together, often touching one another with their flippers.
The calves are nursed for almost a year; it takes four to seven years for the whales to reach puberty, and 15 years to reach full adulthood. Calves do not stop growing until they are ten years old.
Humpback whales are known for their magical songs which are complex with each population singing its own unique song, plaintive sounds traveling large distances through the ocean waters around the world.
These sequences of moans, howls, and cries, often continue for hours on end. It seems that humpbacks sing to communicate with others and to attract potential mates. Twice a year we can admire these joyful giants along our beautiful Costa Ballena.