LAUSR

Generalist species are core components of ecological networks and crucial for the maintenance of biodiversity. Generalised species and networks are expected to be more resilient, therefore understanding the dynamics of specialisation and generalisation in ecological networks is a key focus in a time of rapid global change. Whilst diet generalisation is frequently studied, our understanding of how it changes over time is limited. We explore temporal variation in diet specificity in the honeybee (Apis mellifera), using pollen DNA metabarcoding of honey samples, through the foraging season, over two years. We find that overall, honeybees are generalists that visit a wide range of plants, but there is temporal variation in the degree of specialisation. Temporal specialisation of honeybee colonies corresponds to periods of resource limitation, identified as a lack of honey stores. Honeybees experience a lack of preferred resources in June when switching from flowering trees in spring to shrubs and herbs in summer. Investigating temporal patterns in specialisation can identify periods of resource limitation that may lead to species and network vulnerability. Diet specificity must therefore be explored at different temporal scales in order to fully understand species and network stability in the face of ecological change.