Bionomics of insect pollinators and their interaction with host trees in the orchards of Doda, Indian Himalayas

Abstract

Insect-mediated pollination is critical to the reproductive success of apple (Malus domestica) and apricot (Prunus armeniaca), the two principal cash crops sustaining rural livelihoods in the Himalayan district of Doda, Jammu and Kashmir. Despite this dependence, pollinator community ecology and crop-specific interaction patterns across the elevational gradient of the district remain poorly characterized. This study documents community composition, habitat associations, and host-plant interactions for 13 pollinator species across 10 families and 4 orders during the 2025 blooming season; life-history parameters are derived from published literature synthesis rather than direct life-cycle measurement. A total of 847 individuals were recorded by pan trapping and timed focal observations across six sites spanning 1,073–2,302 m above sea level (ASL). Shannon diversity was strongly associated with elevation (R² = 0.913, p < 0.001), with species richness declining from 13 to 5 and total abundance by 71.8% across the gradient. Family-level compositional turnover was pronounced: Apid bees (Apidae) declined from 39.7% to 22.2% relative abundance, while Halictidae increased from 18.1% to 38.2% at high elevations. At the single co-flowering site (L1, 1,073 m ASL), Apid bees significantly preferred apple (43.9% vs. 27.1% of visits on apricot), and hoverflies (Syrphidae) significantly preferred apricot (42.2% vs. 24.5% on apple). Pollinator Effectiveness (PE) scores, a visitation-based behavioral proxy combining visit duration and stigma contact frequency indicated taxon-specific functional complementarity, whereby bees achieved higher PE on apple and hoverflies on apricot. High-elevation networks exhibited greater modularity (Q = 0.46 vs. 0.38) and specialization (H2’ = 0.61 vs. 0.39), with Lasioglossum moroi serving as a cross-module generalist hub. Niche overlap was lower at high elevations (Pianka’s O = 0.31) than at low elevations (O = 0.58), consistent with increased resource partitioning under environmental constraint. These findings provide baseline data for elevation-specific pollinator conservation in Himalayan agroecosystems. Generalizability is constrained by single-season sampling and restriction of crop-comparison analysis to one site.