What is the keystone species of the Pacific Coast temperate rainforests?

Here is the question :

WHAT IS THE KEYSTONE SPECIES OF THE PACIFIC COAST TEMPERATE RAINFORESTS?

Here is the option for the question :

• Beaver
• Salmon
• Lichen
• Wolf

The Answer:

And, the answer for the the question is :

Explanation:

[STC0010311]. In the temperate rainforests of the Pacific Northwest, the salmon of the Pacific are regarded as the species most important to the ecosystem, which means that the ecosystem cannot function without them. Salmon are an important component of the ecosystem because they transport nutrients from the ocean into freshwater streams. They serve as the principal source of nutrition for a wide variety of marine animals, in addition to bears, wolves, and eagles.