What happened to Yellowstone National Park when wolves disappeared?(1 point)
Responses
The willow tree population increased.
The willow tree population increased.
The bear population increased.
The bear population increased.
The grassy areas increased.
The grassy areas increased.
The deer population increased.
The deer population increased.
The correct answer is "The willow tree population increased" and "The deer population increased." When the wolves disappeared from Yellowstone National Park, it caused a cascade of effects on the ecosystem. Wolves are a top predator in the park, and their absence allowed the deer population to increase unchecked. The increased deer population consumed large amounts of vegetation, including willow trees. As a result, the willow tree population decreased significantly. However, when wolves were reintroduced to the park in 1995, their presence led to a decrease in the deer population, allowing the willow trees to recover. So, the disappearance of wolves led to an increase in deer population and a decline in willow trees.
When wolves disappeared from Yellowstone National Park, several changes occurred:
1. The willow tree population decreased: Without wolves preying on herbivores like elk, their population increased, resulting in overgrazing. This overgrazing led to a decline in willow trees, as the elk were no longer being controlled by the natural predator-prey relationship.
2. The bear population decreased: Wolves often competed with bears for food sources like carrion and small mammals. With the wolves gone, the bear population faced a scarcity of these food sources, causing a decline in their numbers.
3. The grassy areas increased: With the decrease in willow trees and the decline in the bear population, the grassy areas in Yellowstone National Park expanded. This was a result of reduced browsing pressure on the vegetation.
4. The deer population increased: Without predation pressure from wolves, the deer population in Yellowstone National Park experienced a significant increase. This increase further contributed to the overgrazing of plant species, especially willow trees.