Because it seems incredibly strange to see Yellowstone bison fleeing the park, the seemingly unusual bison behavior have sparked fears of an impending Super Volcano, according to an April 4 Christian Science Monitor report. The park recently experienced a 4.8 magnitude earthquake, which has fed into these fears. A super volcano could have devastating effects throughout the region, which makes it very good news that the Yellowstone bison behavior is actually related to something else.
There are roughly 4,600 Yellowstone bison, and many of them are outside of the park right now. So, what is the real reason these bison along with many other Yellowstone animals have moved outside of the park for the spring? Food. These animals are searching for food. Interestingly, the Yellowstone bison and other animals leave the park every year once spring hits, so this phenomenon is not as unusual as a now viral video makes it seem.
The reason they leave Yellowstone is because inside the park, there are still several feet of snow, and in other areas things are beginning to bloom and get green, so the animals' natural instincts are to migrate towards a good source of food. When the snow melts in the park, the animals will find their way back inside because the food will be plentiful there as spring hits.
Even so, Yellowstone is actually on top of a Super Volcano. It is part of what makes the mark so interesting for visitors. Thankfully these Yellowstone bison do not signify any type of eminent massive eruption. The park is well monitored, though, because of the volcano, and it is possible that someday scientists will see that an eruption could be coming. In this case, the animals will also likely sense it, and begin moving out of the area. In the meantime, you can check out the video that has caused all the speculation above.