Nectar from flowers and sugar from running sap (especially at Yellow-bellied Sapsucker holes) or overripe fruit provide most, but not all, of the nutrition that butterflies need. The males of some species will also drink at muddy puddles or damp earth for mineral salts and on scat or animal carcasses to get amino acids and other vital nutrients. This added nutrition is needed for them to generate spermatophores, the packets of sperm and nutrients that are transferred to the female during mating. (Photo is of a White Admiral, Limenitis arthemis arthemis, feeding on blackberry seed-laden Raccoon scat.)
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