Saturday 4 March 2017

Some very basic information about bees

Andrena cineraria (Ashy mining bee)
What's the first thing that springs to mind when you hear the word 'bee'? For many people the word conjures up images of beehives, honey, and people dressed in strange, white, masked outfits; i.e honeybee related images.

Yet, if I gave the same people a box of coloured pencils and asked them to draw me a bee, most would probably draw something black, yellow and white striped, shaped like a rugby ball, with a pair (or two) of wings, two antennae and six legs; basically something more akin to a bumblebee. So there is clearly a little confusion.

I thought it might help if I wrote down some very basic information, to help clear up some of this confusion. Of course there is much, much more to it than what I have written, but hopefully the following will help a little.

There are over 20,000 different species of bee in the world.

7 of these are honeybees.
250 are bumblebees
500 are 'stingless bees'
The rest are, more or less, solitary bees.

In the UK we have around 270 different species:

1 honeybee
24 bumblebees 

245+ solitary bees

NESTING BEHAVIOUR

Honeybees, bumblebees, and stingless bees are all 'social' bees - which means they live together in colonies comprising a queen, female workers, and males. They have a caste system, overlapping generations, and they communicate and co-operate with others in their colonies.

There are tens of thousands of worker bees in a honeybee colony, but only around 50 - 400 in an average bumblebee colony.

With social bees, all the 'worker bees' are female. The males are produced at specific times of the life-cycle for the sole purpose of mating.


                                                        
Solitary bees, on the other hand, do not have 'queens' or 'workers', nor (with one or two exceptions) do they share their nests with other solitary bees. This is why they are called 'solitary'. They do, however, often nest alongside each other. When you see lots of solitary bees nesting in the same area you are seeing an 'aggregation' not a 'colony'.

After mating, female solitary bees set about making their nests. They do this either by excavating tunnels in the ground (ground nesting) or using pre-existing cavities in walls, trees, etc (cavity nesting). Cavity nesting solitary bees are opportunists and will also nest in man-made cavities such as hose pipes, wind chimes, key-holes and teapot spouts! Some species specialise in empty snail shells. A few solitary bee species have become adept at burrowing into rotten wood or pithy plant stems.

Whatever the preferred nest site, each female provisions a number of individual cells with sufficient pollen for larvae to feed on when they hatch. She then lays an egg alongside each lump of pollen, seals each cell (and then the nest), and dies before her young complete their life cycles to become adult bees. These new adult bees remain in hibernation in their nests throughout autumn and winter... and emerge the following year in spring or summer to start their life cycle all over again.
                                                            


HONEY

Only honeybees (and stingless bees) make honey, which they make out of nectar collected from flowers. Honeybees turn nectar into honey to store over winter, so the colony has something to feed on whilst it's too cold to forage, or flowers are scarce.

Other bee species also collect nectar, but do not turn it into 'honey' as we know it. They just use it as an energy drink.



OVER WINTERING COLONIES

Unlike honeybee colonies, bumblebee colonies do not overwinter. Each bumblebee colony produces males and new daughter queens in the summer (at different times depending on the species). These new queens mate and then (mostly) go into hibernation till next spring. The old queen, together with all the female workers and the males, die before winter. That is the end of this nest. So, in a way, you could say honeybee colonies are 'perennials' and bumblebees colonies are 'annuals'.

N.B. Because of climate change, some bumblebee daughter queens now start new colonies before winter, instead of going into hibernation.

                                                             

POLLEN COLLECTING

As well as collecting nectar, bees also collect pollen, which they use to feed their young. Different species collect their pollen in different ways.....

Social bees (honeybees and bumblebees) collect it in pollen baskets on their hind legs. They pack the pollen into these baskets very neatly, so don't drop much off on their way home.

Solitary bees, however, collect pollen on stiff branched hairs, either under their abdomen (cavity nesting species) or on their legs (ground nesting species). It is not moistened or packed down, which means lots of this pollen drops off on the other flowers they visit as they make their way home. This makes them extremely good pollinators.

                                                               

STINGS
Only female bees have a sting. Male bees do not. If a honeybee worker stings you, she dies. If bumblebees sting (which they very rarely do) they will not die. This is because the honeybee sting is barbed, whereas the bumblebee sting is more like a needle. Apart from a few exceptions, solitary bee stings are mostly redundant and incapable of even piercing the human skin.

More on stings here -  Which bees sting and which bees don't? 

                                                                

The most important thing of all is that we provide food and habitat for ALL of these species. They all pollinate different plants, in different ways, at different times of the year, and in different habitats. DIVERSITY is the key. It is equally important that we provide for other pollinating insects like flies,  butterflies, moths, hoverflies, beetles, and wasps.

Photos below are of a honeybee, bumblebee, cavity nesting solitary bee and ground nesting bee.... showing the different ways they collect their pollen.

Apis mellifera (Honeybee)


Bombus terrestris (Buff-tailed bumblebee)


Megachile centuncularis (Patchwork leafcutter bee)


Halictus rubicundus (Orange-legged Furrow-bee)