Seasonal Shift in the Diet Composition of European Bee-EatersMerops apiasterat the Northern Edge of Distribution

European bee-eaters Merops apiaster forage almost exclusively on airborne insects caught on the wing. The availability of this food might be temporally limited due to adverse weather conditions, especially at climatically sub-optimal breeding sites. We determined seasonal variation in the diet composition in adult and nestling bee-eaters at the species' northernmost breeding colonies by analysing food remains from pellets and by direct...