If a House Finch ignores Nyjer seed when other options are present, what is the most likely reason for this rejection?

Answer

A more preferred option, such as black oil sunflower seed, is available.

The refusal of Nyjer seed often signals a matter of preference rather than toxicity, especially when higher-energy substitutes like sunflower seeds are on offer.

If a House Finch ignores Nyjer seed when other options are present, what is the most likely reason for this rejection?
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