Studies have shown that the presence of dragonflies and damselflies indicates low pollution levels in the environment (Lesch & Bouwman, 2018; Ho et al., 2018; Simon, 2012). This is due to their lifecycle, where the insect spends most of its life living in water, hence, water quality is very crucial for their survival (Samways and Simaika, 2016). Poor quality water that is heavily polluted may cause negative impacts on their growth, especially for more sensitive species (Pupke, n.d.). Hence, a water body without the presence of dragonflies and damselflies may indicate that it is polluted. These insects can potentially be natural bioindicators of water bodies within forested areas like freshwater swamp forests (Ho et al., 2018).

In South Africa, the Manual of freshwater assessment for South Africa: Dragonfly Biotic Index is being developed to monitor the health of their precious aquatic ecosystems. Individual species of dragonflies are being studied to assess their value of tolerance towards different climatic and environmental conditions. This index would be useful to assess the health of the environment and can also be applied to the conservation of aquatic ecosystems where it is used to indicate changes to the ecology and environment, especially when there are ongoing developments or changes to the landscapes nearby (Samways and Simaika, 2016).

In Singapore, the National Parks Board (NParks) Dragonfly Watch engages the public to contribute to citizen science study on dragonflies and damselflies. Volunteers would be trained to carry out dragonfly and damselfly surveys along waterbodies around Singapore, in parks, gardens, and nature reserves. The data collected will give the statutory board an idea of the distribution of dragonflies and damselflies. Areas with a lower insect count may indicate a poorer habitat with more heavy metal pollution, hence they can then follow up and improve the management and conservation measures of these locations (National Parks Board, 2020).

 

 

References:

de Moor, F. C. (2017). Dragonflies as indicators of aquatic ecosystem health.

Ho, J. K. I., Quek, R. F., Ramchunder, S. J., Memory, A., Theng, M. T. Y., Yeo, D. C. J., & Clews, E. (2018). Aquatic macroinvertebrate richness, abundance and distribution in the Nee Soon freshwater swamp forest, Singapore. Gard. Bull. Singapore, 70(Suppl 1), 71-108.

J Samways, M., & P Simaika, J. (2015). Manual of freshwater assessment for South Africa: Dragonfly biotic index.

Lesch, V., & Bouwman, H. (2018). Adult dragonflies are indicators of environmental metallic elements. Chemosphere, 209, 654-665.

Pupke, C. (2019, July 18). Dragonflies – Important Environmental Indicators. Retrieved November 05, 2020, from https://www.biophiliafoundation.org/dragonflies-environmental-indicators/

Simon, M. (2012, June 11). Dragonflies – Indicator Species of Environmental Health. Retrieved November 05, 2020, from http://www.earthtimes.org/nature/dragonflies-indicator-species-environmental-health/2033/