The spatial distribution and the composition of wild bee speciesavailable for pollination of early strawberry varieties in four different countries
Abstract: Field margins can serve as habitat for beneficial insects. In conservation of beneficialsan understanding of the spatial distribution and range is crucial. Few studies have investigatedhow wild bee species richness, abundance and species size is distributed spatially in crop fieldsand how response may be affected by geographical location. We assessed the composition of wildbee species available for pollination of early strawberry varieties as affected by field margin typeand geographical location. Bees were sampled at the field middle and two types of field marginsin 14 early flowering strawberry fields in five different geographical locations: Mid-Norway,South-Norway, Denmark, Sweden, and Germany giving a North-South gradient of approximately1100km. Preliminary results show that catch per day was higher in Denmark and Germany thanin the two study areas in Norway. The soil-nesting genus Andrena (Hymenoptera: Andrenidae)was generally very common in all geographical regions and dominated the samples in thesouthern regions, whereas Bombus (Hymenoptera: Apidae) were more frequent than Andrena inthe Northern study areas and virtually absent from Danish and German samples. It remains to betested how bee species richness, abundance and species size is distributed spatially in thestrawberry fields across the study locations.