Spicebush Swallowtail

One creature's scat is another creature's treasure! It's not uncommon to see butterflies sitting on the ground, sucking up fluids from scat or mud. This behavior is called “mud-puddling”. Butterflies do it in order to gain certain nutrients that they can't get from nectar, such as salt, nitrogen, protein, and amino acids. Male butterflies especially seem to benefit from the extra sodium intake which increases their reproductive success. The extra sodium is often transferred to the female with the spermatophore during mating as a nuptial gift. This enhanced nutrition also increases the survival rate of the eggs. While mud-puddling often takes place on wet soil, desperate butterflies will also seek nutrients from sweat, blood, and feces.