How will certain things influence the size of the population
Immigration will increase the size of the population because more giraffes will be added to the population. Immigration might occur because there is plenty of resources for the new giraffes.
Emigration will cause the population of the giraffes' to decrease because giraffes are leaving the population. This might happen because giraffes won't have enough resources.
Birth: Births will increase the size of the giraffe population because it is adding more giraffes to the population. Births increases with the availability of resources.
Death: Deaths will decrease the size of the population because more giraffes are dying. Deaths just happen to every species when they get old or are hunted as prey and makes resources available.
The size of the giraffe population will depend on the amount of resources that the population has. At the start a slow growth in the population followed by exponential growth until limited resources when carrying capacity is reached. At carrying capacity the giraffe population will be as big as it could get. If the giraffes have enough food and water to have a growing population they will eventually reach carrying capacity.
The density-dependent limiting factors that might impact the size are food and disease. Food is one because there might not be enough to go around and disease is one because if one giraffe gets a disease it can spread kill off other giraffes.
Two density-independent limiting factors that might impact the size of the population are temperature, drought. Temperature because of the are the giraffes live is very hot and that temperature may be enough to kill the giraffe. Also drought because if there isn't enough water that could cause the giraffes to die.