Changes in Population Size
Changes in population happen every year from death or birth.
Births and Deaths
An individuals population grow mostly by birth. Most birth rate are fast. Unlike humans animals have there baby really fast. For example a female rabbits can have 6 babies in one year while a human might not have a baby in one year. But also rabbits can also die quicker than humans. Humans may have babies later on, but are very protective. So, rabbits have a lower population than human because there are deadly animals that eat rabbits a lot. This shows how most population go down.
Immigrants and Emigrants.
Another way population and decrease is if an animal or animals are emigrating their population to immigrate to different forest. This is another way of how population decreases. This happens because sometimes there is not enough food or water for the whole population, so some of them leave to a new population. Also, sometimes the animals are fighting for food and get competitive, so that causes the losing animal to leave because he has no food to eat.
Penguins Emigrating There Home
These penguins are emigrating do to low amount of food.
Reindeer immigrating To a New Home
The reindeer has found a new home to live in.
An Elephant
This elephant is leaving the forest do to the carrying capacity of the forest.
Graphing Changes in Population
Graphing changes in population helps you find out what is the carrying capacity, how much food there is, or what is the population is over the year. Graphing can help you on all these things.
This is a graph of a cottontail rabbit population from 1983 to 2013.