Thug life: bramble ( <scp> <i>Rubus fruticosus</i> </scp> L. agg.) is a valuable foraging resource for honeybees and diverse flower‐visiting insects

Abstract

Abstract Bramble ( Rubus fruticosus L. agg.) is a common summer‐flowering plant native to the United Kingdom. Multiple complementary approaches were used to evaluate its ecological value to the honeybee ( Apis mellifera ), bumblebees ( Bombus spp.) and other flower‐visiting insects in Sussex, England. Regional surveys of insect groups at seven sites across 2 years showed that foraging activity on bramble was dominated by honeybees (60.2%; n = 28 surveys) and bumblebees (17.4%), compared to non‐ Apis/Bombus bees (2.8%), hoverflies (Syrphidae, 7.9%), non‐syrphid flies (0.6%), butterflies (6.4%), wasps (0.4%) and beetles (4.4%). Foraging insect community structure was highly similar spatially, but varied significantly between survey months (June and July). In detailed local surveys at one rural and one urban location, there was a diverse range of insect taxa foraging on the bramble flowers, including species of conservation concern ( Bombus humilis , Coenonympha pamphilus and Limenitis camilla ). Pollen trapping at 12 honeybee hives in four locations showed that an average of 31% of pollen pellets collected by honeybees from late May to early August were bramble, with a peak of 66–86% per location. Bramble was present in 54 out of 60 200 × 200 m randomly selected grid squares surveyed over a large area across Sussex. Plants were recorded in multiple habitat types in both urban and rural areas. Bramble is sometimes considered an undesirable plant or a “thug” that outcompetes other wild flowers; however, these findings confirm that it is highly valuable for flower‐visiting insects. Wherever conflicts of interest and management strategies allow, bramble should be maintained and promoted for wildlife and insect conservation.

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