Reddish Vale Country Park
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species worldwide.
Bumble bees are social insects that are characterised by black and yellow body hairs, often in bands. However, some species have orange or red on their bodies, or may be entirely black. Another obvious (but not unique) characteristic is the soft nature of the hair (long, branched setae), called pile, that covers their entire body, making them appear and feel fuzzy.
Like their relatives the honey bees, bumble bees feed on nectar and gather pollen to feed their young.
Bumble bees form colonies, which are usually much less extensive than those of honey bees. This is due to a number of factors including the small physical size of the nest cavity, the responsibility of a single female for the initial construction and reproduction that happens within the nest, and the restriction of the colony to a single season (in most species). Often, mature bumble bee nests will hold fewer than 50 individuals. Bumble bee nests may be found within tunnels in the ground made by other animals, or in tussock grass. Bumble bees sometimes construct a wax canopy ("involucrum") over the top of their nest for protection and insulation. Bumble bees do not often preserve their nests through the winter, though some tropical species live in their nests for several years (and their colonies can grow quite large, depending on the size of the nest cavity).
Bumble bee nests are first constructed by over-wintered queens in the spring. Upon emerging from hibernation, the queen collects pollen and nectar from flowers and searches for a suitable nest site. The characteristics of the nest site vary among bumble bee species, with some species preferring to nest in underground holes and others in tussock grass or directly on the ground. Once the queen finds a site, she prepares wax pots to store food, and wax cells to lay eggs in. These eggs then hatch into larvae, which cause the wax cells to expand isometrically into a clump of brood cells.
Bumble bees generally visit flowers exhibiting the bee pollination syndrome. They can visit patches of flowers up to 1–2 kilometres from their colony. Bumble bees will also tend to visit the same patches of flowers every day, as long as they continue to find nectar and pollen, a habit known as pollinator or flower constancy. While foraging, bumblebees can reach ground speeds of up to 15 metres per second (54 km/h).
Experiments have shown that bumble bees are able to use a combination of colour and spatial relationships in learning which flowers to forage from. After arriving at a flower, they extract nectar using their long tongue ("glossa") and store it in their crop. Many species of bumble bee also exhibit what is known as "nectar robbing": instead of inserting the mouthparts into the flower normally, these bees bite directly through the base of the corolla to extract nectar, avoiding pollen transfer. These bees obtain pollen from other species of flowers that they “legitimately” visit.
Queen and worker bumble bees can sting. Unlike a honey bee's stinger a bumble bee's stinger lacks barbs, so they can sting more than once. Bumblebee species are not normally aggressive, but will sting in defence of their nest.
Bumble bees are important pollinators of both crops and wildflowers.
Bumble bees are increasingly cultured for agricultural use as pollinators because they can pollinate plant species that other pollinators cannot by using a technique known as buzz pollination. For example, bumble bee colonies are often placed in greenhouse tomato production, because the frequency of buzzing that a bumble bee exhibits effectively releases tomato pollen.
The agricultural use of bumble bees is limited to pollination. Because bumble bees do not overwinter the entire colony, they are not obliged to stockpile honey, and are therefore not useful as honey producers.
Bumble bees are in danger in many developed countries due to habitat destruction and collateral pesticide damage. In Britain, until relatively recently, 19 species of native true bumble bee were recognised along with six species of cuckoo bumble bees. Of these, three have dissapeared in certain regions, eight are in serious decline, and only six remain widespread.
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Reddish Vale Country Park