Answer:
The most prominent factor that is causing the moose population to decrease, is the climate change, and the second most important one, is human hunting and destruction of the moose´s natural environment, and feeding grounds, to increase availability of land space for cattle raising. And the decrease of the moose population, as they are the main pray for wolves, causes these predators to move away, die, or seek other sources of food, which means that as the moose population decreases, so does the wolf population, for different reasons.
Explanation:
As researched, probably the biggest reason for the decreasing in many species of animals, not just the moose, is climate change, because climate change is affecting the environment of animals, and changing their living habits to adapt. The affectation of plant life, the changes in availability of water and living space for wild animals, such as the moose and wolf, are leading to their decreased numbers. However, hunting by humans has also become a problem, even though today legally, most of these hunting activities are restricted and controlled. A third, and very huge issue, is the human encroaching on the environments where both moose and wolf live, in order to turn lands into grazing lands for cattle. Farming, thus, has also become a problem that has led the moose to either seek other environments, or die off. As a chain reaction, the wolf population also decreases, as they either die, or move away since they no longer have easily available prey to hunt.