This is a textbook example of trophic cascade, where predators influencing the behaviour of their prey species drastically influences species elsewhere on the “food chain” or trophic level.
And it’s amazing.
This is a short documentary on this subject on wolves in Yellowstone:
here’s a slightly longer one (with surprise!narrator Edward Norton):
Everything is connected.
Those are Elk that the wolves are chasing in the video. That is an important distinction because deer are small and generally not a threat to humans, but Elk are BIG. (They ARE a member of the deer family, but so are moose and pudu so that description isn’t all that helpful.) Mature male Elk weigh more than 700 lbs (315 kg). For comparison moose, the largest member of the deer family, weigh between 800 and 1500 lbs (360 to 680 kg) for males. Mule deer and whitetail deer (which are the species of deer that most Americans know) weigh 100 to 130 lbs (45 to 60 kg). Why does this matter? Because Americans hear “deer” and think of something the size of a small woman. They come to Yellowstone, or other places in the West and instead find something 7 times that size. Non-Western Americans are used to deer being afraid of them. Elk are not afraid of you, especially the ones in Yellowstone which have near constant interactions with tourists. I am telling you all this because when people (who generally are thinking “big deer” rather than “small moose”) interact with Elk, people get hurt. During the fall when the Elk are in the rut, Male Elk will attack cars (probably a reflection thing again), Menacing Bushes, other Elk, and, most dangerously, people. During the spring when the female Elk have babies, the female will attack anything that may threaten her baby, including wolves! You are not tougher than wolves. Elk can and have killed humans. Do not mess with Elk. (Also do not mess with moose but they are not as densely populated in Yellowstone. Also do not mess with Bison. They are bigger than moose.)
As a side note, rangers in Yellowstone HATE the fall because the bull Elk are chasing the cow Elk and running all over the place. People keep getting too close so they can Observe the Natural Behavior. The rangers have to spend so much time warning people to stay away from the Elk, stay over here by the buildings, avoid the sharp stabby antlers and flying sharp hooves, wait to go to your car until the Elk leave, as well as rescuing people trapped by Large Violent Elk, that they have no time to do anything else. They often get burnt out. As September approaches, Yellowstone rangers become grimmer, more serious, less friendly, grittier in preparation for the rut. Do Not Mess With Elk. Yellowstone Rangers Will Thank You. Also You May Survive Your Visit to Yellowstone.
Tumblr backup 