Question

A stream runs through a mountain forest. Willow trees grow on each side of the stream. A small deer population feeds on the willows. Mountain trout rely on the willow shade for shelter. The apex predator in the forest is the mountain lion. The mountain lions primarily eat deer, but also eat rodents, and fish, as well as other prey species.

Analyze the components of the ecosystem. What is the most likely outcome if the mountain lion population vanishes?

(1 point)
Responses

The stream will become polluted.
The stream will become polluted.

The trout population will decrease.
The trout population will decrease.

The deer population will increase.
The deer population will increase.

The deer population will decrease.

Answer 1

If the mountain lion population vanishes, the most likely outcome would be that the deer population will increase. Mountain lions are apex predators, and their absence would remove a significant predator from the ecosystem, allowing deer numbers to rise without the constraints of predation. This could lead to overgrazing of the willow trees, which could potentially have cascading effects on the entire ecosystem, including the trout population that relies on the willows for shelter. Thus, the correct response is:

**The deer population will increase.**