Why are Hooded Orioles often referred to as 'nectar robbers'?

Answer

They often pierce the base of a flower to sip the sweet fluid

They gain the reputation of nectar robbers because they frequently bypass the pollen-gathering mechanism by piercing the base of a flower to sip the nectar, thus not aiding in pollination.

Why are Hooded Orioles often referred to as 'nectar robbers'?
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