T-perches foster insectivorous bird activity and regulate insect guild composition in mustard agroecosystems

AbstractThis study evaluated the effectiveness of artificial T-perches in enhancing avian activity and modulating insect community dynamics across three organically managed sites in Punjab, India (PAU, Ghelewal, Pakhowal) during the Rabi seasons of 2022 and 2023. A total of 44 bird species were recorded, with insectivores comprising 56.8% of total observations. T-perch plots recorded a significantly higher weekly bird visitation rate (31.6 ± 3.2 individuals) compared to control plots (22.4 ± 2.9), with prominent species such as Dicrurus macrocercus (Black Drongo, 32.64% perch use) and Acridotheres tristis (Common Myna, 16.65%). Species richness peaked at PAU (24), while species diversity and evenness were highest at Ghelewal (2.57 and 0.90, respectively), reflecting spatial heterogeneity in community composition. Perch-provisioned fields exhibited significant reductions in major pest populations including Lipaphis erysimi and Athalia lugens, with up to 22 and 18% decline in abundance, respectively. Notably, pollinator species such as Apis dorsata and Apis cerana remained unaffected, and the European honey bee (Apis mellifera) showed stable presence across treatments.