How Does the Butterfly Fit in the Food Web?

Stages of Life

• As an insect, the butterfly has four basic stages of life: egg, larva, pupa and adult. The two stages in which it is active are the larva and pupa stages. During these two separate stages, it will interact with other organisms in different ways, thus inhabiting a different part of the food web.

Food as a Larva

• In the larval stage, the butterfly is commonly called a "caterpillar." Caterpillars generally feed on one specific type of food, usually plants. Because of this, adults will lay their eggs on that specific type of plant. During the larval stage, caterpillars feed voraciously on these plants, becoming very plump and big.

  Though most caterpillars eat plants, there are some carnivorous caterpillars. In North America, the harvester caterpillar feeds on aphids, while Hawaii's Eupithecia caterpillars feed on a variety of other insects.

Food as an Adult

• Most adult butterflies are very unobtrusive creatures. Instead of destroying plants like caterpillars do, most of them merely stick their long snouts into flowers and drink the nectar. However, some adult butterflies--like the adult harvester--feed on such things as dung and carrion. There are no adult butterflies known to be predatory.

Caterpillar Predators

• Due to their general plumpness and inability to move quickly, many caterpillars become the prey of various predators during this stage. Such predators include spiders, wasps, birds and small mammals.

Adult Butterfly Predators

• Many adult butterflies--such as the monarch--are poisonous to most would-be predators. However, even the monarch has to fear specific animals that have a tolerance for their poison. The black-eared mouse, black-backed oriole and black-headed grosbeak all feed on the monarch. Similar predators--mostly birds, small mammals and spiders--exist for other butterfly species around the world.