Population Size There are four factors that change population size. These factors are Immigration – People entering a country for various reasons. Birth Rate – The number of births of a sample size per 1000 people per year. Birth Rates are affected by many factors such as the ability to receive health care, family planning, the use and availability of contraceptives, governmental policies, economic growth, education, social and cultural views, and the use of abortion. Death Rate – The number of deaths of a sample of per 1000 people per year. Death rates are caused by the lack of availability of food and water, lack of education, disease, lack of medical care, suicide, car accidents, crime, war, and government entities. Emigration – People leaving a country for various reasons. The birth rate is most affecting the population size of the nutria. With the population growing so rapidly eventually there will be no more food left for them where they are and they will be forced to migrate to another city or state. They are eating up all of the vegetation and unless another predator starts eating them than there will be nothing left for them to eat so they will have to move where they can get food. When they get finished with Louisiana there will be nothing but water left and it will take many years for things to get back to normal if they ever can get back to normal. I feel that before they move to another state they will be in towns and cities all over Louisiana. Eventually they will be everywhere and in every state if we are not careful. The way that they multiply it would not take long for the situation to get out of control if it hasn’t already. When the food supply starts running low for the nutria if they do not migrate somewhere else than they will starve and eventually be extinct.