Background Paragraph: In nature, when the population size is small, there is usually plenty of food and other resources for each individual. When there is plenty of food and other resources, organisms can easily reproduce, so the birth rate is high. As the population increases, the food supply, or the supply of another necessary resource, may decrease. When necessary resources, such as food, decrease, some individuals will die. Overall, the population cannot reproduce at the same rate, so the birth rates drop. This will cause the population growth rate to decrease. 
Story: A team of biologists has been monitoring the deer population in the state of Wisconsin. They use past data and current conditions to predict if the population will grow quickly or slowly and recommend how many hunting licenses the state should issue during hunting season to keep the population stable.
If a diseased crop has dropped resources will the biologists predict the birthrate will increase or decrease? If a plentiful crop has increased resources will the biologists predict the birthrate will increase or decrease? If the deer birth rates went down this year when compared to last year does that mean that resource availability went up or down? If the deer birth rates went up this year when compared to last year does that mean that resource availability went up or down?