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How Do Wolves Change Rivers? [VIDEO]

Why does the reintroduction of wolves change rivers?

Ask Yellowstone National Park, which experienced an incredibly influential ‘trophic cascade’ after wolves were brought back to the area after a 70-year absence.

What is a trophic cascade, you ask? Luckily, shared this video, narrated by George Monbiot, which explains the phenomenon. It’s essentially an ecological process that starts at the top of the food chain and falls down to the bottom.

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In 1995, Yellowstone was at a point in which deer and elk populations were largely increasing. These animals did a number on vegetation and plant life, essentially impacting the food supplies for many other organisms.

What happened once the wolves were brought in, and how were the rivers in the Park eventually changed? Watch the video to see:

It’s incredible what one species can do to every other species in that ecosystem. The most interesting part involved the erosion and movement of river water, as it responded to the wolves’ presence. Vegetation recovery led to less soil erosion, which led to less banks crumbling over time.

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What’s your initial reaction to the idea of trophic cascade? Have you heard of or witnessed any other such incidences? Leave your thoughts below.

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How Do Wolves Change Rivers? [VIDEO]