Landscape composition influences colony growth in the tropical asian stingless bees ( Tetragonula fuscobalteata )

摘要

Context Pollination is an important ecosystem service for both crop and wild plants. In recent decades, many pollinators have been experiencing population declines due to land-use changes and intensified agriculture. However, effects of anthropogenic landscapes on bee pollinators in the tropics are still little investigated.Objectives We analyzed the effects of landscape composition on the colony weight as well as foraging activity and patterns of the tropical Asian stingless bee species Tetragonala fuscobalteata which is a vital generalist pollinator in Southeast Asia.Methods Twenty-eight colonies were established and monitored over a year in 19 mixed fruit orchards located along a gradient of human land-use intensity.Results Our results revealed that the colonies gained weight and increased their foraging activity over time across diverse landscapes including forest, agricultural, and urbanized areas, indicating that this bee species can well adapt to anthropogenic landscapes. Interestingly, T. fuscobalteata colonies also gained weight rapidly in orchards located in predominately agricultural landscapes with e.g. high proportions of rubber and oil palm plantations as well as in fruit orchards (such as rambutan, durian, coconut, banana). This positive effect was possibly due to mass flowering crops providing abundant resources, i.e., pollen and nectar, for a limited time. We also show that T. fuscobalteata foragers could rely on urbanized land (probably ornamental plants and some crops in home gardens and backyards) and wild plants in surrounding forest patches during non-flowering periods of crops.Implications for insect conservation Our results can contribute to land management design to promote biodiversity and enhance pollination services. As resource continuity and diversity at the landscape scale are vital for insect pollinators, we suggest preserving natural forest areas, planting many crop species within agricultural lands, and providing flowering plants in suburban or urban gardens.Conclusions Our findings indicate that despite land-use intensification, the generalist pollinator, Tetragonala fuscobalteata, which is commonly used in meliponiculture in Southeast Asia, can persist in highly modified anthropogenic landscapes with the combined floral resource availability, including agricultural fields, urbanized areas and forests. We consider landscape management as a possible way to support these native pollinating insect populations by not only establishing highly heterogeneous landscapes, but also by creating suitable resource-rich sites facilitating pollinator movement between human-modified landscapes and natural habitats.