Butterflies are Picky Eaters
The task for the adult butterfly is to find a mating partner, to produce offspring, and to give the next generation the best start in life. During this period sugar rich nectar is taken in, provided by many flowers. Usually, butterflies are opportunistic when choosing those flowers.
Once mating has occurred, the female spends about half her time searching for nectar locations, pollinating plants in the process, and the other half of her time finding the right host plant(s) to lay her eggs on.
Once the plant has been located, eggs are deposited on the leaves. When the caterpillar emerges, a period of constant feeding starts. The larva consumes around five times its own weight everyt single day, and will have increased its body size 1000 times, possibly more, before it pupates. It needs the quantity and the nutrition to get through the pupal (chrysalis) phase and reach adulthood.
What happens if the female butterfly can't find the right host plant? The answer is simple. The caterpillars will not survive. Not enough people know that, and don't realise how few food plants some of the butterfly larvae have available.
Australian butterflies have evolved to coexist with and depend on native host plants. Urbanisation has led to habitat loss and the disappearance of native flora. Exotic garden plants have replaced indigenous provenance. Some butterfly larvae have been able to adapt alternative plants, most have not.
If we want to see butterflies in our lives, it is of the utmost importance to ensure that native host plants remain in our environment and are introduced back into our gardens, school yards and bushland.
Image: Sylvia Alexander