For whales mating and bearing offspring starts by leaving their local feeding grounds and traveling to their native mating environments.
Depending on the species some whales may travel thousands of miles from their feeding grounds to their mating grounds where they look for a mating partner or give birth to their young.
Although whales are known to migrate there are species that inhibit the same area throughout the year or follow the migration patterns of their food rather than looking for an ideal mating environment.
For many species mating season occurs during the colder winter months when their food supply migrates to warmer climates and their native feeding grounds begin to freeze or become extremely cold.
In order to find a more stable environment these whales will travel towards the equator where the weather is warmer and produces a suitable environment for mating and having children.
As stated earlier though not all species migrate and some may feed and breed within the same area.
Once mating season arrives and the whales are ready to mate the guys begin looking for a mating partner by courting the female whales.
The courtship period
The first phase a male whale goes through when it attempts to find a female mating partner to reproduce with is to attract a female whale during a courtship phase.
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 among 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.
To give each male the best opportunity for reproducing some species produce large amounts of sperm which is believed to help wash out the previous males sperm in an attempt to bear its own offspring.
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.