Mud-puddling butterflies

Butterflies at stream crossing

It is not uncommon to see a kaleidoscope of different butterflies gathering on wet sand and mud at stream banks in Mountainlands Nature Reserve. They visit these areas to sip nutrients such as sodium, other minerals and amino acids which can be lacking in feeding on the nectar of flowers alone. This behaviour is called puddling. It is more common in males than females as males need the nutrients during mating. It is believed that the additional sodium affects their courtship flight and they incorporate it into their sperm and transfer it to the female during mating. In one study researchers found that males that consumed sodium courted more energetically and had greater mating success than males that consumed water. Females lose sodium when they lay eggs, but they don’t need as much as they receive it from the male partner during mating. It is believed that the transfer improves survival of the eggs.
Butterflies can also get their nutrients from sources such as dung, carcasses and even sweat on human skin.