The Black-footed ferret
The Black-footed ferret is an obligate associate of the prairie dogs. The Black-footed ferret depends on prairie dogs as a primary food source and upon their burrows for shelter from weather and predation. The ferret is completely dependent upon prairie dogs for survival. Prairie dogs constitute about 90% of the ferret's diet.
The wolves at Yellowstone National Park's main source of food is the Elk. Wolves usually travel in packs and attack herds of Elk so that it is more beneficial to the whole pack. Elk are about 80% of Yellowstone wolves food source.
Mountain lions depend on elk as their main source of food due to when the mountain lions are usally found in Yellowstone, elk are the most convenient for them.
The badgers main food source are the ground squirrel since they are smaller when it comes to feeding their young. Badger usually dig a hole for their young or take one from the prairie dogs and place their young there while they go to find the prey for their young.
Lynx usually are found in area of Yellowstone with the most snow and due to that finding prey can be hard at times, but their main food source are the snowshoe hares.