According to research, wild bees may be just as content visiting woodland tree tops as they are among the flowers at ground level. The shaded interiors of woodlands are generally thought to be unsuitable for sun-loving bees. A new study, however, reveals that a diverse community of wild bees is active high above the shade, among the branches and foliage of the trees in the sunlit woodland canopy.
According to new research from the University of East Anglia, wild bees may be just as happy visiting the high canopy of woodlands as they are among the flowers at ground level. The shaded interiors of woodlands are generally thought to be unsuitable for sun-loving bees. A new study published today, however, reveals that a diverse community of wild bees is active high above the shade – among the branches and foliage of the trees in the sunlit woodland canopy.
The team say that woodland canopies may play a more significant role in bee conservation than previously thought, with nectar and pollen-rich Sycamore trees proving particularly attractive to bees. Dr Richard Davies, from UEA’s School of Biological Sciences, said: “Wild bees are a major contributor to crop pollination services, but to thrive in agricultural landscapes they also need non-crop habitats to provide places to nest and flowers to feed on.
Our findings show that wild bees have the potential to exploit the abundant sources of nectar and pollen available in woodland canopies. Nectar-producing trees, such as Sycamore, are likely to provide a significant food source for many bee species, and some may even collect pollen from wind-pollinated trees, such as Oak.
Dr. Richard Davies
“Shaded woodland interiors are often considered poor foraging habitat for bees, but until now, bee activity in the sunlit woodland canopy has scarcely been investigated.”
Lead researcher Guthrie Allen, also from UEA’s School of Biological Sciences, said: “We wanted to find out more about the potential for the woodland canopy to support wild bee communities.”
The team investigated bee communities across 15 woodland sites in a farmed landscape in Norfolk in late spring. They examined levels of bee activity in four habitats – in the canopy (at heights of up to 20 metres) and understory of both woodland interiors and exposed woodland edges.
Allen said: “We found that a diverse community of wild bees are active in the woodland canopy — by which we mean high up among the trees’ branches and foliage. Activity levels were particularly high near flowering Sycamore trees. We also found that bee communities differ between the woodland canopy and understory – the layer of vegetation growing close to the woodland floor. And we were surprised to find that most bee species were just as abundant in the understories of woodland interiors as they were at the sun-exposed edges bordering farmland.”
“Our findings show that wild bees have the potential to exploit the abundant sources of nectar and pollen available in woodland canopies. Nectar-producing trees, such as Sycamore, are likely to provide a significant food source for many bee species, and some may even collect pollen from wind-pollinated trees, such as Oak.”
“Our findings also indicate that the understory of managed woodlands has the potential to support bee communities.” More research is needed to understand why communities differ between the canopy and understory, but our findings suggest that woodlands play a larger role in supporting farmland bee communities than previously thought.”
