In relation to the monarch population, the total area covered by the monarch population in Mexico shows a decreasing trend. From 8 hectares in 1995, it dropped to 2.5 hectares in 2015. This indicates that there is a significant drop in the population of monarch butterflies. Factors that limit the population growth of the monarch population, such as predator-prey relationship, competition, natural disasters, deforestation, pollution, and destruction of habitats, are contributing to this event.

It is likely that the population of the predators or the organisms that consume or harm monarch butterflies in their winter homes are increasing. This claim is supported by the decreasing number of hectares that are covered by the monarch population. Aside from the predator-prey relationship that serves as a limiting factor to the population of the monarch, there is also a possibility that the drop is due to deforestation or usage of herbicides that destroy milkweed plants, nectarine habitats and other food sources of these butterflies.

Here are the possible questions which we can ask to identify the limiting factors that influence the population of monarch butterflies:

1. Is there an organism that consumes monarch butterflies?
2. Are there parasites that attack monarch butterflies?
3. Are the food sources scarce or abundant?
4. What are the things that might affect the number of eggs that a monarch butterfly produces?
5. What is the ideal temperature and amount of precipitation for growing monarch butterflies?
6. Is there any sign of pollution, deforestation or severe weather conditions?