Friday Fun Fact – What Do Butterflies Eat?

Ever wondered what do butterflies eat?

Firstly, they don’t really eat – not as humans or other animals do, anyway!

A butterfly’s mouth part is made up of two lobes, like straws, which are joined together. This means they can only drink liquids.

Butterflies spend about 50% of the time looking for food. They are generally associated with flowers because they need the high energy from nectar which is mostly sugar. Flying takes a lot of energy!

Flowers make up the bulk of their diet, but there are many other sources of food for the discerning opportunist.

They do need other nutrients like nitrogen, salts and amino acids. These can be found in tree sap, wet soil and flower pollen. Somewhat less appealing, they can also get these nutrients from rotten fruit or vegetables, faeces, urine, sweat, tears and (the least attractive of all) rotting carcasses!

These nutritional needs stem from the caterpillar’s food. Plant have almost none of the salts that all animals need. Even plant eating mammals like horses and cows need salts – this is also why plants need fertilisers.

When butterflies mate, the male will give the female a package of these nutrient and salts, plus everything else she needs to fertilize her eggs. The female will use this package to provision her eggs. This shortens the time a female spends looking for these compounds and gives her more time to concentrate on finding host plants and laying eggs. This has led to a big difference in feeding habits of male and female butterflies.

Often, large groups of mostly male butterflies can be seen congregating around muddy puddles or creek beds. This is called “Mud Puddling” or “Puddle Clubs”. Males will often visit plants and flowers that the female shows no interest in. These plant have compounds that are precursors for the pheromones the males use to entice a female to mate with them. Females can assess the male’s ability to provide the nutrients by their body odour.

Food is not just about filling your tummy – turns out it’s very important for social activity as well!