There are four factors that produce changes in population size. Starting with immigration, in which a group of animals including humans will move to an area where is not persevered for the changes that will take place because of the immigration. A group of mammals called Nutrias were migrated from South America to Louisiana. The Nutrias reproduce like rabbits, therefore the increase in birth rate is extremely high and ruining the crops in the Louisiana. There were no signs of war or famine, towards these small creatures; they seem to be very healthy and adapting to the environment very quickly. The only famine is towards the crops in the state, the Nutrias eat anything in the color green. I would have to say that after the mammals eat up all the crops, they will move on until they find other resources. If they get large enough they can travel in groups, is only natural. I am not sure they will be wiped off the earth. Unless we take them back one by one to their birth of place, then they can be completely gone from North America. These animals adapt quick and reproduce fast, they will be around for a long time.