Pollution puts fireflies, butterflies at risk

The number of butterflies and fireflies in the country is dwindling due to rising environmental pollution, traffic, pesticides, artificial lights and the growing trend of ornamental plants.

Several types of butterflies are being bred in Punjab but there is no centre for research on fireflies. The number of the insects is declining rapidly in the country. Entomologist Nazneen Seher, who is in charge of the Butterfly House in Jallo Botanical Garden, told The Express Tribune that the main reason for the extinction of these insects is the poisonous sprays applied on the crops. Butterflies and fireflies eat earthworms, mosquitoes and other small insects but due to the poisonous spray, these insects are becoming extinct. However, butterflies and fireflies are found in areas where toxic pesticides are not used.

Fireflies are found in large numbers in semi-mountainous areas and near canals with mosquito larvae abound. The Head of Biology Department at Lahore College for Women University, Dr Farkhunda Manzoor said the number of butterflies and fireflies was much lower now than it was 30 or 40 years ago and the biggest reason of this was climate change. According to her, another reason is that the local plants on which butterflies used to thrive are no longer being cultivated and ornamental plants have taken their place. She said that in order to increase the breeding of the insects, local plants should be cultivated and biological agents should be used instead of pesticides.

Biologists also point to telecommunication signals and artificial lights as a major threat to fireflies. The female fireflies live on the land, while males fly in the air and scatter light. Fireflies use the light emitted from their bodies to communicate with each other but the artificial lights disrupt this process. There is a Butterfly House for rearing of the insect in Lahore, but a plan to set up a centre for research and breeding of fireflies at the Jallo Garden has not been implemented. Nazneen Sahar said there are thousands of types of butterflies. So far 58 species of butterflies have been discovered in Punjab and out of them eight local and non-local species are being bred in the Butterfly House.

Butterflies live from one week to one year with each type having its own lifespan. In severe cold weather, they either die or migrate to favourable areas. In areas where the weather is mild, more species of butterflies thrive. Some species change their appearance to suit the climate, due to which they are also able to withstand climate change. The types that are bred at the Butterfly House include monarch, plain tiger, little yellow, lemon, orange sulfur, common mormon, yellow glassy tiger and others. The expert said that cabbage white butterflies grow more in winter.

The temperature at the Butterfly House is maintained at 28 to 33 degrees because it is suitable for their rearing. The spring months of March-April and August to mid-November are the seasons of butterfly breeding