Exploring the importance of floral resources and functional trait compatibility for maintaining bee fauna in tropical agricultural landscapes

Loss of semi-natural habitats has been identified as a major driver for pollinator loss in agricultural landscapes. The challenge has been addressed in developed countries by creating flower strips and pollinator habitats in agricultural areas, but this approach has largely been overlooked in developing countries. However, even in countries that adopted pollinator-friendly measures, the complementarities between functional traits of plants and bees are not generally used as selection criteria for candidate species in floral strips. Furthermore, the combined effect of habitat variables that are likely to maximize bee visitation are also overlooked. In tropical developing countries, even the basic information to inform decision making is missing. This paper attempts to bridge this critical gap and reports how assemblages of different non-crop plants could be used to attract bees in tropical small landholdings by investigating non-crop plant identity, non-crop floral traits, bee traits and influential habitat variables at patch scale. Results showed that a combination of both non-crop flower density and diversity increased bee visitation at patch scale. Moreover, trait-based analyses revealed that bees with a larger inter-tegular distance, longer tongue frequently visited flowers with a longer corolla. This study demonstrates that both characteristics of non-crop flower patches and floral traits are important for effective management of non-crops in tropical farmland to attract pollinators with complementary functional traits. We have explored a range of non-crop plants that could be effectively sown to attract bees but recognise that more research is necessary in order to standardise their propagation, establishment and management techniques.