Abstract
Many studies have looked into the benefits of organic farming on soil ecology, but their effectiveness in biodiversity conservation, especially in bird communities in the organic ecosystem of Tamil Nadu, is less investigated. This research was conducted to determine the effects of organic farming methods on bird species, frequency and diversity in the Cauvery deltaic region of Tamil Nadu specifically, in rice ecosystems. In the Thaladi season of September and October 2022, bird monitoring was carried out in five pairs of organic and conventional rice habitats. This research documented a total of 726 birds, represented by 31 species, 19 Families and 11 Orders. Insectivorous birds were the most abundant species in organic rice ecosystems when compared to conventional ecosystems. This was observed across all three dietary guilds namely insectivore, granivore, and omnivore. A study on birds indicated that they had a higher value of species diversity in organic ecosystems (H = 3.06 Shannon-Weiner Diversity Index, R = 31 Species richness, J = 0.89 Evenness). In contrast, species diversity in conventional ecosystems was lower (H = 2.80, J = 0.87 and r = 25). This research has empirically demonstrated the advantages of organic farming, particularly in the Cauvery Deltaic region's organic rice habitat. It also provides quantifiable evidence that clearly shows its effectiveness in increasing the number of avian insectivores.
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