The first phase of reproduction is the courtship period.
During the courtship period unrelated male whales will compete for female whales to show their worthiness and gain the right to mate with the female first.
Some of these courting activities include breaching (Lunging out of the water), fin slapping (slapping their fins against the water) and singing (producing low-frequency melodic tones).
Some species of whale may also charge at one another and fight over a female whale.
Although male whales are known to compete amongst one another for the right to mate with a female it is rare that a whale will cause severe physical harm to one another.
A few species of whale such as several of the beaked whale species are known to be quite aggressive and may scar other whales or obtain fractured beaks from intense fighting.
In many of the whale species it is common for the female to mate with several males in a single season to increase her chances of producing offspring.
Most whales will migrate to warmer tropical temperatures during mating season and toward colder weather during their feeding period.
Although whales migrate to warmer climates during mating season the winter months seem to be particularly popular for migration and mating among many of the species.
The male whales reproductive organs (genitals) are enclosed in a cavity during swimming to streamline swimming and protect the males organs.
The gestation (pregnancy) period
Just As humans have a pregnancy period female whales also carry their children in their uterus during their gestation period (the time it takes to go from conception to birth).
The gestation period for a female whale can be anywhere from 10 months to 17 months and varies from one whale species to the next.
While in the uterus the baby whale receives nutrient rich blood through the umbilical cord.
Many of the females in the whale species will have calves every one to four years or so while they remain fertile.
During birth calves will generally end up being born tail first to aid in avoiding the possibility of the calf drowning, however some calves are born head first.
Female whales produce a thick whale milk which is excreted from their nipples, through the water and to their calves mouth.
The thickness and consistency of the whales milk helps minimize the chance that the milk will dissolve in the water.
On average it takes a whale 7 to 15 years to sexually mature, at which point the whale will be capable of bearing offspring of its own.
Whales can grow anywhere from two to four times their size on average from birth to adult hood.