In almost all cases the female gives birth to a single offspring every 1 – 6 years.
Gestation periods can vary greatly depending on the whales species and can be anywhere from 9 months to 18 months long!
During this voyage some species will even give up eating and will fast for the entire trip which could last several months.
Note: Although some species of whale migrate there are other species that will only travel short distances from their home over the course of their entire life.
Once the whales arrive at their mating grounds the males then begin competing with one another for the right to mate with the female.
These competitions can be anything from vocalizing their desire to mate (whale songs) to performing acrobatic feats such as lunging and leaping out of the ocean, slapping their tails and flippers against the water and charging at other male whales.
After a male establishes his dominance and mates with the female other male whales may continue to challenge one another to try to mate with the same female whale.
It is not uncommon for a female whale to mate with several male whales during a single season as most species are not monogamous.
When mating season ends the whales make the long journey back to their feeding grounds where they restock on food.
During these months the impregnated female whales go through what’s known as a gestation period (the period from conception to birth) which can last for 9 – 18 months.
After birth the female whale feeds her young by producing milk which her child then suckles on from her nipple.
In most cases the milk contains a very high fat percentage of 35% or higher fat concentration.
This high concentration of fat causes the milk to come out very thick which helps to prevent it from breaking apart in the water.
The milk is full of nutrients that the baby whale needs to grow healthy.
Suckling may continue anywhere from 6 months to 2 years or more until the child is fully able to separate psychologically and/or due to the mother no longer producing milk.
In a family the female whale is referred to as the cow, the male is called the bull and the child is known as the calf.