Diversity and abundance of aquatic insects of the natural ponds at the Jahangirnagar University Campus, Dhaka, Bangladesh

Abstract

The investigation into the diversity and abundance of aquatic insects encompassed five ponds within Jahangirnagar University, Dhaka, Bangladesh, spanning from in the rainy month June 2023 to January 2024. A comprehensive tally revealed 4134 insects across 18 genera, distributed among 15 families and 5 orders. Predominant orders included Hemiptera (74.41%), Coleoptera (9.58%), and Odonata (8.08%), with non-Insect Orders represented by Acarina (3.97%) and Araneae (3.97%). Peak insect abundance occurred in July 2023, contrasting with the lowest count observed in January 2024. Among the species, Back swimmers ( Notonecta ) exhibited the highest relative abundance at 58.11%, while Riffle ( Velia sp .) displayed the lowest at 0.83%. Correlation analysis unveiled positive associations in June between insect population and environmental factors such as temperature (31.5℃), water pH (7.51), and dissolved oxygen levels (17.01mg/L). Notably, Hemipteran (34.33%) and Coleopteran (5.64%) insects dominated, indicative of lower pollutant levels within the surveyed pond areas. The study underscores the dynamic nature of aquatic insect populations, influenced by seasonal fluctuations and temperature variations. These findings offer insights into the intricate ecological dynamics within aquatic ecosystems, emphasizing the sensitivity of insect communities to environmental changes.