When it comes to the various types of seasons for marine mammals such as whales their seasons can be broken down into two primary seasons known as mating season and feeding season.
Depending on the species of whale and where they live their mating season can vary, but it typically occurs during the colder fall and winter months where whales can take advantage of the warmer tropical climates near the equator.
These marine mammals may also migrate due to the fact that their food supply may migrate away from some of the colder environments causing their prey to become scarce and limited during the winter.
Migration
Every year a number of different whale species travel several thousand miles to their mating grounds to mate and give birth to their offspring.
During mating season these whales will travel from their northern and southern polar hemispheres towards the equator to take advantage of the warmer climates.
Some whales will travel to environments that offer better protection from predators such as killer whales so that they can give birth to their young while minimizing their chances of being injured or having their children attacked by predators.
During these long voyages certain species of whale will fast and live off of the energy stored in their blubber that they gained during their feeding period.
Blue whales for example will travel several thousand miles during mating season and will eat virtually nothing for up to 4 months while they travel.
And humpback whale are known to make one of the longest migration trips of any known animal and will travel up to 16,000 miles or more in a single year at an average speed of 1 – 3 mph.
In fact thousands of humpback whales will travel from both the northern and southern hemisphere during their respective mating seasons, but rarely run into one another because the seasonal climate changes are different between the northern and southern hemispheres, so their mating seasons are different.
As stated earlier where the whale lives will partially determine when and where they will migrate to.
It is important to understand however that not all species of whale make long migration trips and some species will migrate simply to maintain their food supply rather than for mating purposes.
Bowhead whales for example will stay in Antarctic waters throughout the year, regardless of the season.
While they may travel from one location to another in the Antarctic waters, they do not make long migrations like the humpback or blue whales..
The migration of killer whale on the other hand is largely determined by the migration of their prey.
Killer whales that consume fish and squid as the primary source of their diet will migrate to where they can find these sources of food while killer whales that consume seals, sea lions and other marine mammals will follow those sources of food when and if they migrate.
There are also species such as the sperm whale that will meet up during mating season to mate with the female whales and once their mating season ends the males will go off on their own without following any particular migration patterns and leave the females to take care of their offspring.
In terms of where these marine mammals live whales can be found all over their world, however there location can vary based on the particular species of whale.
Note: The killer whale is actually a dolphin and belongs to the toothed whale suborder.
Courtship
When the whales finally arrive at their mating destination they begin courting the female whales and will display various shows of physical health and youth by breaching, tail slapping, spy hopping and in some cases even charging other males.
Some whales will attempt to hoard the female away either alone or in a group with other males in an attempt to retain breeding rights.
Other male whales (such as the humpback) will produce loud melodic tones often referred to as whale songs (because the sounds seem almost musical) which occur mainly during mating season.
Scientists believe the sounds are used to attract female whales for mating purposes and when one singing male comes into close contact with another it can often lead to anger and aggression.
Reproduction
During the course of their mating season it isn’t uncommon for a female whale to mate with several adult males to maximize her chances of reproducing a healthy offspring.
Some male whales will produce large amounts of sperm when mating with the female in an attempt to wash out the previous males sperm and improve their own chances for impregnating the female.
Once the female whale is impregnated it can take anywhere from 9 – 17 months before birth occurs depending on the species.
The period between conception and birth is known as a gestation period which is very similar to the pregnancy periods humans go through when having a child.
Once the female has given birth to her newborn she will nurse the child and provide it with milk which she produces from her mammary glands.
This nursing period may last anywhere from 6 months to 2 years or until the child can survive on its own and break away from its psychological dependency on its mother.
Once the child reaches sexual maturity, which can vary between 5 – 20 years depending on the whales species, it can begin mating and reproducing on its own.
In regards to how long whales live the lifespan of various species can range from 20 – 200 years.
In fact a healthy bowhead whale can live for 200 years making it one of the longest known living animals alive today.
The end of mating season
Once the mating season is over the whales will migrate back to their feeding grounds in the northern and southern polar hemispheres where they will eat and restore their energy reserves for the next seasonal migration.
In some cases the adults will leave the mating grounds first to guide the way with the female whales who have just given birth leaving last with their newborn children.
Dolphins, Porpoises and Mating
While some species of whale are known to make long migration trips from their feeding grounds to their mating grounds dolphins and porpoises aren’t known to make these migration.
Depending on where these marine mammals live they may be seen migrating from coastal to offshore waters during certain times of the year, such as when the coastal waters begin to freeze during the winter, however they aren’t likely to travel thousands of miles away from their local environment the way whales do.
River dolphins such as the Amazon river dolphin may migrate from their local rivers to larger parts of the Amazon during rain season when the local rivers begin to flood.
Once the drought season comes around these marine mammals will travel back to their local rivers until the next rain season occurs.
When it comes to mating dolphins and porpoises are able to mate any time of the year, however some species may tend to having a higher mating frequency during certain times of the year, which can in some ways be considered a mating season.