Nectar pointers for gardeners as bumblebees prove to be unfussy eaters

Ecologists said the most common species of bumblebee are not fussy about a plant’s origin when searching for nectar and pollen among urban gardens.

Other species – in particular long-tongued bees – do concentrate their feeding upon plants from the UK and Europe, for which they have developed a preference evolved over many thousands of years.

But Plymouth University academics have warned that if native plants were to disappear completely from British gardens, the long-term survival of some common pollinators, such as the garden bumblebee, could be under threat.

The study set out to examine whether bumblebees preferentially visited plants with which they share a common bio-geographical heritage.

Researchers conducted summer-long surveys along a typical residential street.

Their findings showed that rather than discriminating between Palaearctic – a range extending across Europe, north Africa and northern Asia – and non-Palaearctic garden plants, bees simply visited plants in proportion to flower availability.

Indeed, of the six most commonly visited plants, only one – foxglove – was a British native and only three of Palaearctic origin.

Among individual species, however, there were distinct preferences, with the long-tongued garden bumblebee showing a strong preference for “native” Palaearctic-origin garden plants, choosing them for 78 per cent of its flower visits.

Meanwhile, the UK’s most common species – the buff-tailed bumblebee – favoured non-Palaearctic garden plants over species with which it shares a common evolutionary heritage.

Ecologist Dr Mick Hanley, from Plymouth University, said the findings showed the continued importance of promoting diversity and encouraging gardeners to cast their net wide when choosing what to cultivate.

Paul de Zylva, from Friends of the Earth, said: “This study underlines the importance of native wild bees, which have been ignored by ministers for far too long.”