Wildlife watch Look out for the clever little honey thieves who are robbing nectar from your flowers
Scottish Wildlife Trust’s Falls of Clyde Wildlife Reserve Ranger Laura Preston would like to tell readers about unusual behaviour she spotted in her garden.
I was out admiring my garden one morning last week and as I watched the bumblebees on my aquilegia, I noticed some odd behaviour.
The bumblebee was visiting the outside of each of the flowers but not going into them.
My first thought was that the bumblebee was a bit sleepy and kept missing the flowers, but after closer inspection I had one of those ‘light bulb’ moments.
This bee was nectar robbing; it happens when a short-tongued bee (in my case it was a white-tailed bumblebee) wants to get the nectar from a flower with a long corolla.
Their tongue is too short, but they have strong mandibles, so they can instead bite a hole in the base of the flower. This means they can then reach the nectaries with their short tongue.
The only downside to this is that the flowers aren’t pollinated in this process.
Nectar robbing is quite a common occurrence, and often after the primary robber has made its exit, other bees and insects will come along to ‘take their piece of the pie’ so to speak.
This can include other bumblebees, but also hoverflies and honey bees. Interestingly, it seems bees are more likely to rob if there is competition for nectar.
If there aren’t many suitable flowers with short corollas, the shorttongued bees will have to rob the flowers with long corollas, otherwise they wouldn’t be able to get enough nectar.
Next time you are out, have a look to see what the bumblebees are doing.
Common plants that are robbed include comfrey, aquilegia and delphinium.
After inspecting the other flowers in my garden, I noticed many, if not all, had been robbed.
That makes me think I should be planting other flowers with short corollas, in order to provide an equal amount of food for all my bumblebee visitors.