Anyone who has made their way along the Midlands Meander will know that it is represented by a butterfly. This little guy, known to entomologists as Orachrysopsariadne, is restricted to the Karkloof and Merrivale area because of its life cycle.
Like most Lycaenids, its larval stage depends on specific plant and ant species. This fussy eater is extremely vulnerable to environmental changes, which constantly occur as humans encroach on the butterfly’s habitat. Farmers, town planners or property developers have done this for centuries. The first documented case of the extinction of a British butterfly was recorded in 1847. There are approximately 670 species of butterfly in South Africa, of which 40 run the risk of becoming dodos.
All habitats continually change, whether they are natural or man-made. However, under the influence of humans, the countryside is changing so rapidly that most creatures cannot adapt to the changes fast enough. Hectares and hectares of land will be allocated to crops or pastures for livestock. These are human necessities which invade the home of the butterfly and could be life-endangering to it.
Farmers clear large areas
A large portion of butterfly sustenance is removed when a farmer ploughs several fields to produce corps. If the area is wetland, it will be drained or the water table lowered, or springs will be capped, so that the all-important crop can be planned and large amounts of pesticides applied.
Timber farmers have a more gradual effect on the land to start off with, but also result in an environment which is useless for butterflies. Since the sunlight cannot penetrate the trees onto the forest floor, all groundcover plants are eliminated. This not only exposes bare soil, it allows the wind to blow through the plantation. Butterflies avoid wind-blown locations.
As for pastures, which are cultivated for cattle, sheep or goats, butterflies will still be deprived of nectar and larval food plants. The animals trample the flowers. Where overgrazing occurs, a decrease in plant diversity, or bare soil, will result. In urban areas lawns are mowed to look neat and tidy, with the same results as when animals graze there. Add to this the human need for sports fields, factories, mineral extraction sites, highways and other tarred roads, and the butterfly is left with nowhere to go.
Butterfly enthusiasts kill indiscriminately
To make matters worse, butterfly enthusiasts indiscriminately kill butterflies to pin them into their collections! Why not photograph them? The SA Butterfly Conservation Assessment project, with its foundation in the Lepidopterist’s Society of SA, is asking the public to do just that. This way a virtual museum is being created, that is viewed by all and is also a good way of keeping track of the butterflies seen out and about.
Bird watching is another hobby that has a negative impact on these insects. By providing food, nest boxes or any other conceivable convenience for the birds, the disproportionate increase of birds to butterflies leaves them with more predators than it can handle.
Suitable habitats are destroyed and isolated, making it impossible for diminished butterfly populations in one area to be naturally replenished with those from another.
Once their home environment is destroyed they cannot survive, since they have extremely specific habitat requirements. They might be able to adapt to the new and different resources, but because this takes time, and these changes occur almost overnight, adaptation is impossible. The final result is extinction.
What can we do?
- People need to make space for butterflies. Many of the plants that appeal to gardeners do not necessarily suit the butterfly. Flowers such as roses, lilies or chrysanthemums are attractive, but open-flowered composites, e.g. daisies, are preferable to butterflies. Indigenous flowers and flowering trees are a good way of attracting butterflies to your garden: Butterflies need scent, nectar, bright colours, and a source of food for the caterpillars.
- The use of insecticides should be avoided. They only have a temporary effect often resulting in an unnatural insect population explosion the following season. Weedicides will starve the caterpillars. A good substitute for pesticides would be soapy water, which will ‘wash’ the pests away. Incorporating more biodiversity, even in your vegetable garden, will ensure natural pest protection and do stop excessive weeding, as weeds could act as a deterrent anyway.
- Another technique that could be employed to protect your vegetables is companion gardening. This involves planting herbs or garden plants, such as marigolds, alongside the vegetables which confuse the pests and attract other predators. Certain pungent herbs, such as wild garlic (also called Tulbaghia), repel the pests.
For those who haven’t seen these beauties en masse, go to Butterflies for Africa in Pietermaritzburg; or the Butterfly World in the Cape Winelands. Each has a hot house in which the butterflies flit about happily and there are experts on hand to answer any questions you might have about them. Butterflies are a good indicator of the health of our environment: the less we see of them, the more we can be sure that our environment is unhealthy and/or filled with pollution. So put the effort into finding out more about them and about ways to improve the environment we share with them.
Butterfly photo: Blue-banded Swallowtail
(Article first appeared in Farm Focus, January 1998)
By Ilze Gertenbach