Which smaller, more timid species might be discouraged from using a feeder monopolized by assertive House Finches?

Answer

Pine Siskins or American Goldfinches

Due to their social nature and tendency to arrive in numerous, assertive flocks, House Finches can monopolize feeding stations, sometimes discouraging smaller, more timid species like Pine Siskins or American Goldfinches from accessing resources.

Which smaller, more timid species might be discouraged from using a feeder monopolized by assertive House Finches?
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