Dr Konstantinos Tsiolis is searching for signs of Wool Carder bees (Anthidium manicatum) nesting in this park bench in Christchurch Greyfriars Garden, in the City of London, near to St Paul’s Cathedral.

The hunt was carried out in June 2024 during a pollinator survey for Pollinating London Together. Konstantinos had mentioned to me that he’d found the bees nesting there in 2022, so I suggested we see if they are still using it.

Wool carder bees like to nest in cavities in wood, so it makes sense that in an urban environment they would look for an existing hole in manmade wooden structures like a park bench. Once they’ve found a suitable dark, dry cavity with enough space to lay a few dozen eggs, they need to collect fibres from specific plants to cram into the nest on which to lay their eggs. Their favourite is the soft fibres from the leaves of the Lamb’s ear plant. Below we can see the opening of the rectangular hole under the arm of the bench has been plugged with what appears to be Lamb’s ear fibres.

We didn’t actually see any bees coming and going from the bench, so we’re not sure if this is an active nest or an old one. The Wool carder bees had only started to fly when we found this nest, so we will have another look in July to see if there is any action.

Above (left) is a Wool carder bee on the Lamb’s ear flowers, and on the right is a wonderful close up photo of a Wool carder bee where it’s yellow stich-like markings are clearly visible.

You can try to help Wool carder bees, by drilling 12mm diameter holes into a wooden log and placing them near to the Lamb’s ear plant.