I don't know whether you know this already but of the 267 species of bee in the U.K. and Ireland, 90% of them are solitary bees. Solitary bees don't produce honey, aren't social, don't live in hives and don't produce honey. They don't swarm and are not aggressive, in fact male solitary bees don't sting and females will only sting if roughly handled.
One of the reasons solitary bees are non aggressive is that they don't have a hive to defend. 70% of solitary bees are mining bees and nest in underground burrows, the rest nest in cavities in banks or walls and are known (predictably) as cavity nesting bees. It is the cavity nesting bee which benefits from the little wildlife hotels made from bamboo tubes or similar which we'll look at in a minute.
Solitary bees are much more efficient pollinators than honey or bumble bees. In general they are hairier and, like a child in a high chair, get their dinner all over the place. Like the bee emerging from a pumpkin flower above, solitary bees get covered in pollen as they move from flower to flower; they don't have pollen sacks like social bees so drop a lot more with each visit. This makes them fantastic pollinators, a singe red mason bee (a cavity nesting bee) is equivalent to 120 worker honey bees in the pollination service it provides.
Providing nesting sites for cavity bees
The ideal accommodation for cavity bees are long hollow tubes. In nature they are unlikely to come across a pile of neatly cut bamboo poles, they nest in dry, hollow plant stems of perennial wild flowers, but the shelter bamboo provides is ideal.
The female bees pack the poles with balls made of pollen glued together with nectar, these are food stores for the developing larvae. She places the pollen ball in the tube and lays an egg on top before building a partition wall and repeating the process until the pole is filled. The end is sealed with mud, leaves or hairs depending on the bee species so you can see what mix of bees you have by the capping they use. The most likely tenants you will find in a bamboo bee house will be the red mason bee, the leaf cutter bee and the wool carder bee, I'll leave you to guess how to recognise their characteristic nest caps.
We have a new range of wildlife habitat products coming in next week including the ceramic pollinator habitat above. We'll have some wonderful natural looking designs from the 'Wildlife World' brand who have been designing, testing and building insect habitats for over 20 years. I don't have the products ready to ship yet so haven't included them below but will be adding them to next Friday's mail.