Bumblebee gathering nectar from a borage flower
There are nearly 20,000 known species of bees, they are found on every continent except Antarctica. Bees are adapted to gather nectar and pollen from flowers. Nectar is a sweet substance, produced by some plants to attract pollinators such as bees, butterflies, bats etc.
Bumblebee gathering nectar from a comfrey flower
Pollen is a fine powder of microscopic particles from the male flower that can fertilise the female flower to produce seed. Pollen is produced by anthers, the male reproductive organs found in most flowering plants. Bees collect pollen in pollen sacs on their hind legs, which can be seen in the picture, one can tell what plant they collect it from depending on the colour.
Bumblebee with two types of pollen from different flowers on the pollen sac on it’s hind leg, on a knapweed flower
Nectar provides an important energy source (carbohydrate) – it supplies a complex range of sugars, while pollen provides vital protein and fats. Although all bees need pollen at some stage in their lives, not all bees gather it. Also in their attempts to get at the nectar many pollinators do transfer pollen, ensuring fertilisation for the flower.
Bees may be solitary or may live in various types of communities. Honey bees and bumblebees live in communities, having cooperative brood care and a division of labour into reproductive and non-reproductive adults, plus overlapping generations. The true honey bees (genus Apis) colonies are established by swarms, consisting of a queen and several hundred workers (daughters). Honey bees live in hives, and wild ones live in old tree-trunks and other such sites while bumblebees live in nests sometimes on the ground. This weekend I came upon a bumblebee nest on the ground that had been attacked perhaps by a badger, they do attack the nests and eat the bees, and there were some poor bees there with destroyed eggs.
Carpenter bees, leafcutter bees and mason bees are solitary bees.
Nectar contains about 80% water, along with complex sugars. In order to store the sugars in a usable and efficient state, bees convert the nectar into honey. Honey contains only 14-18% water, therefore honey provides a much greater energy source than pure nectar. Using its straw-like proboscis, a worker bee drinks the liquid nectar and stores it in a special stomach called the honey stomach. The bee continues to forage, visiting hundreds of flowers, until its honey stomach is full. Within the honey stomach, enzymes break down the complex sugars of the nectar into simpler sugars, which are less prone to crystallization. This process is called inversion. With a full belly, the worker bee heads back to the hive and regurgitates the already modified nectar for a hive bee. The hive bee ingests the sugary offering and further breaks down the sugars. It then regurgitates the inverted nectar into a cell of the honeycomb. Now, the hive bees beat their wings furiously, fanning the nectar to evaporate its remaining water content. As the water evaporates, the sugars thicken into honey. Once the honey is finished, the hive bee caps the beeswax cell, sealing the honey into the honeycomb for later consumption.
Honey bee gathering nectar on a Buddleia
It is therefore very important to leave wildflowers flourish, to grow bee-friendly plants, and for wild sites to be left for bees to create nest sites etc. One can also create nest boxes.
Honey bee on a knapweed flower, gathering nectar, with pollen on its body