Using DNA metabarcoding to investigate honey bee foraging reveals limited flower use despite high floral availability

Abstract

Understanding which flowers honey bees (Apis mellifera) use for forage can help us to provide suitable plants for healthy honey bee colonies. Accordingly, honey DNA metabarcoding provides a valuable tool for investigating pollen and nectar collection. We investigated early season (April and May) floral choice by honey bees provided with a very high diversity of flowering plants within the National Botanic Garden of Wales. There was a close correspondence between the phenology of flowering and the detection of plants within the honey. Within the study area there were 437 genera of plants in flower during April and May, but only 11% of these were used. Thirty-nine plant taxa were recorded from three hives but only ten at greater than 1%. All three colonies used the same core set of native or near-native plants, typically found in hedgerows and woodlands. The major plants were supplemented with a range of horticultural species, with more variation in plant choice between the honey bee colonies. We conclude that during the spring, honey bees need access to native hedgerows and woodlands to provide major plants for foraging. Gardens provide supplementary flowers that may increase the nutritional diversity of the honey bee diet.

Quantitative and qualitative assessment of pollen DNA metabarcoding using constructed species mixtures

“…Small-scale studies have demonstrated proof of concept, and the field has advanced significantly over the past few years. Pollen DNA (meta)barcoding has been applied to airborne allergen monitoring (Kraaijeveld et al, 2015), plant-pollinator interactions (Bell, Fowler et al, 2017;Galimberti et al, 2014;Keller et al, 2015;Richardson, Lin, Quijia, et al, 2015a;Richardson, Lin, Sponsler, et al, 2015Sickel et al, 2015 and quality control of honey (Hawkins et al, 2015;Valentini, Miquel, & Taberlet, 2010;de Vere et al, 2017). Its potential has also been recognized for examining changes in plant communities over time (Suyama et al 1996;Parducci, Suyama, Lascoux, & Bennett, 2005, Parducci et al, 2017, and in forensics .…”

Generalisation and specialisation in hoverfly (Syrphidae) grassland pollen transport networks revealed by DNA metabarcoding

“…This approach compares samples of mixed DNA sequences recovered from pollen with a library of plant species sequences (Hawkins et al, 2015). DNA barcodes have been successfully recovered from pollen carried by bees (Bell, Loeffler, & Brosi, 2017;Bell, Fowler, et al, 2017;de Vere et al, 2017;Wilson, Sidhu, LeVan, & Holway, 2010). DNA metabarcoding therefore has the potential to offer an insight into pollen transport by hoverflies, by allowing the identification of mixed pollen samples from individual hoverflies without requiring specialist palynological expertise (Bell et al, 2016).…”

Flower preferences and pollen transport networks for cavity‐nesting solitary bees: Implications for the design of agri‐environment schemes

“…While plant identification from DNA has presented numerous challenges (CBOL 2009), it has the advantage of providing finer definition of species‐specific foraging preferences for plant families whose pollen is difficult to distinguish morphologically (Bell et al., 2016; Bruni et al., 2015; Hawkins et al., 2015; Kraaijeveld et al., 2015; Pornon, Andalo, Burrus, & Escaravage, 2017). DNA sequencing has been used successfully to identify the foraging preference of honeybees and the floral composition of their honey (Bruni et al., 2015; De Vere et al., 2017; Galimberti et al., 2014; Hawkins et al., 2015; Jain, Jesus, Marchioro, & Araújo, 2013; Valentini, Miquel, & Taberlet, 2010). Several studies have also used pollen DNA sequencing to identify solitary bee foraging preferences (Sickel et al., 2015; Wilson, Sidhu, Levan, & Holway, 2010).…”