Cuckoos have left the UK, yet cuckoos remain.

Cuckoos, parasitic birds of reed warblers and other host birds, may have left the UK for their African winter quarters, yet cuckoos remain.  Cuckoo bumblebees, that is, which can commonly be seen in gardens.

Buddleia or butterfly bushes are visited not just by butterflies but also by bees.

Red Admiral

Large White

Comma

Buff-tailed bumblebees

For example, here are a couple of Buff-tailed bumblebees, Bombus terrestris.  The larger, with a buff coloured tail is a queen.  The smaller, with a white abdominal tip is a worker or a male.

Buff-tailed bumblebees

Queens produced in late summer are fertilised and hibernate over winter until next spring when they start a new colony.  All the other bees in the nest die.  (Although with milder weather in the south, some nests may survive the winter.)

Southern Cuckoo bee

On this same bush yesterday in my West Sussex garden was a Southern cuckoo bee, Bombus vestalis, which is a parasite of Buff-tailed bumblebees.

Southern cuckoo bee and a honey bee

Buff-tailed bumblebee queen (foreground) and a cuckoo bee (top)

Just like the cuckoo bird, cuckoo bumblebees lay their eggs in a host bee's nest, which is cuckolded into rearing the cuckoo bee's progeny.

Bumblebees and honey bees are vital pollinators of plants.  Solitary bees play an even greater role.  

Advice for gardeners wishing to maintain a bee-friendly garden is avaiable from the Bumblebee Conservation Trust at https://bumblebeeconservation.org/get-involved/gardening-for-bees/

"The extraordinary lives of wild bees and the important role of gardeners in their survival" is one of my talks on natural history, details of which are at http://www.peterlovetttalks.co.uk/page15.html

All these photo's were taken in my garden yesterday, 14 August 2017.  Click on any picture to expand it.  For my other talks please see http://www.peterlovetttalks.co.uk/