Question

Which food source’s scarcity caused the Yellowstone National Park beaver population to decrease?
fish, grass, willow, otter

Answer 1

The scarcity of **willow** has been a significant factor in the decrease of the beaver population in Yellowstone National Park. Beavers primarily rely on willow, along with other woody plants, for food and building materials for their dams and lodges. A decline in willow availability directly impacts their population.