The wildflower turf and sedum on this roof only feeds bees in mid summer and later, so we suggested to Savills, which manages the building, the garden designer and the maintenance contractor that they add crocuses, wallflowers and other earlier flowering plants to feed bees from spring 2022.
We also suggested installing a 3m square x 4m deep mound of sand packed down and with logs around the base drilled with holes. The idea is to provide a place where mining bees can nest and also solitary bees that like to nest in wood. On another London roof where a similar structure has been built, the following bees have been recorded nesting:
- Buffish mining bee (Andrena nigroeanea) and it’s cuckoo Early Nomad bee (Nomada leucophthalma)
- Common mini miner bee (Andrena minutula)
- Furrow bee (Lassioglosum)
- Orange-legged furrlow bee (Halictus rubicundus)
- Orange-tailed mining bee (Andrena heamorrhoa)
- Chocolate mining bee (Andrena scotica).
We also installed bee hotels for mason bees and leafcutter bees to use.
Unfortunately, the roof isn’t accessible to staff working in the building, so we suggested in 2022 that Urban Bees visit each month from late spring to late summer to monitor bee visitors and report back to staff.
In 2022, we spotted:
- Leafcutter bees (Megachile) on knapweed
- Common carder bees (Bombus pascuorum) on wildflowers
- Furrow bees (Lasioglossum) on daises
- Buff-tailed bumblebees (Bombus terrestris) on vetches
- Buff-tailed bumblebees (Bombus terrestris) on Bird’s foot trefoil
- Honeybees (Apis mellifera) on achillea.
In November, I spoke to the staff of NBC Universal who are tenants of the Central St Giles about the work Urban Bees is doing to rewild the rooftop to help a variety of wild bee species throughout the spring and summer.
We will monitor in 2023 for more bee species and record if any species are nesting on the roof.