Giant Carpenter Bee!

Dear All

On a recent hike in southern Tanzania at the edge of the Uluguru Mountains I came across one of East Africa’s largest bee: the Giant Carpenter Bee (Xylocopa nigrita).

This is a striking bee where the males and females are sexually dimorphic: meaning that they look very different. The females are boldly marked in black and white, while the males are covered in bright golden hairs that glisten in the sunlight.

Females visit flowers of many different species, and on this day they were feeding on flowers of legumes (a Crotolaria sp.) and also the flowers of pigeonpea (Cajanus cajan), which they are responsible for pollinating. Working the legume flowers requires a lot of skill and dexterity from the bees. The flowers need to be ‘tripped’ so as to expose the pollen from the anthers that slide out of the keel of the lower petals. The carpenter bees are experts at doing this:

While the females are busy visit flowers the males set up territories that they patrol during the day. These are usually near patches of habitat that females frequent. Male carpenter bees spend many hours flying back and forth around their territorial patch marking landmarks with scent and watching for females.

After a hard days’ work, they too visit the flowers for some refreshment in the form of nectar.

Several people have asked me how exactly I take these photos of bees. The key thing is patience and waiting at the flowers, with some understanding of the movements and behaviour of the bees. It took me over an hour of watching and waiting to get these photos of the Giant Carpenter Bees.

More from the wonderful world of insects soon!