October 11, 2016

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The Alkali Bee

November 5, 2011 By

The alkali bee is an unusual ground-nesting sweat bee native to arid regions of the western United States. The alkali bee prefers to nest in bare soil where water leaches from below to the surface, the soil is moist but not wet and is dry on top. This occurs naturally in areas where a layer of hard-pan exists in alkali soils. The alkali salts form a crust sealing the top of the soil and holding in the moisture.

The alkali bee is slightly smaller than a honey bee and has yellow or green irridescent bands on its abdomen. The female has a stinger but rarely uses it and no protective clothing is needed to handle these bees. The female carries pollen on her back legs to her nest which she has dug in the soil. Most nest cells are between 4 and 8 inches below the surface. The pollen is moulded along with nectar into a ball, then the female lays an egg on the ball and seals the cell. The egg hatches and the larva feeds on the pollen and nectar ball until it reaches the mature larval stage. It overwinters in this stage and then pupates and emerges as an adult in the spring. There is usually a single generation each year, however in California there are often two generations.

Commercial usage

Alkali bees forage on a wide variety of flowers but are particularly attracted to alfalfa (lucerne) and onion seed and pollinates these very efficiently. Commercial alfalfa seed growers use the alkali bee for pollination in parts of the Western United States. They maintain or construct special alkali bee beds, near the crops to be pollinated, to cultivate thousands of bees, often with populations of up to 125 nests per square foot in these artificial beds.

Read more about Sweat Bees

Filed Under: Solitary Bees , Sweat Bees Tagged With:

Meet the Hairy Footed Flower Bee.

October 20, 2011 By

The hairy-footed (spring) flower bee (Anthophora plumipes) also known as the plume-legged bee, appears very much like a small bumble bee, but is in fact a type of mason bee.This bee is a solitary bee as the female builds her nest and provides food for her young, unaided by others of her species.

The hairy-footed flower bee is a common early visitor in the South of Britain (but not in Scotland or Ireland) and is also extensively found in mainland Europe, where they are present in a variety of colours. They have also been recently sighted on the Eastern side of the United States. Their rapid, darting flight pattern is quite distinctive and they rarely land on a flower for very long, often just hovering by it while they extract the nectar with their characteristically long tongues which cannot be fully retracted.The sexes are very different (sexual dimorphism), the female hairy-footed flower bee is black with a fringe of yellow hairs on her back legs and the males are ginger coloured with yellow faces. They can only be seen from the start of March to late May and as such are important early spring flower pollinators.

The hairy-footed flower bee life cycle.

The adult male emerges first followed by the females about two weeks later. The males are very territorial and will guard an area of flowers that the females like to visit or a suitable nesting site, in the hope of encountering a passing female.The male aggressively patrols this patch and will chase off any intruders, whether they are a competing flower bee or not. You will see him noisily fly at full speed into any other passing insects, knocking them out of the way.

Once mated the female will begin the task of nest-building. She will typically nest in old soft stone walls, with a high sand or lime content , mortar joints, south-facing cliff faces and more rarely in the ground. Under the right conditions there can be large numbers of these bees nesting alongside each other, only then may there be damage to the structure they have chosen. The female hairy-footed flower bee`s nest usually consists of a single burrow, or a series of branching burrows each ending in one or more circular or oval chambers known as cells. A completed nest usually contains about six to twelve cells.

Before sealing the cell the female bee deposits a supply of pollen and nectar, then lays an egg on top and seals it up with soil or mortar. Male eggs are laid last and will be nearer the top of the nest as they will hatch first. Both male and females develop into fully formed adults by the end of summer, but remain over winter in their sealed cells ready to emerge in early spring.

By Maggie Roberts

To learn about Beekeeping see http://www.beekeepingbeesandhoney.com/

Filed Under: Mason Bees , Solitary Bees Tagged With:

October 20, 2011 By

The leafcutter bee is a solitary bee which along with mason bees and carder bees belongs to the family Megachilidae.This family of bees is notable for the fact that their pollen carrying apparatus (called a scopa) is restricted to the under surface of the abdomen, rather than mostly or exclusively on the hind legs as in other bee families.The leafcutter bee takes its name from its method of nest-building.

As a solitary bee the leafcutter bee does not live in a colony like the honey or bumble bee.The female is solely responsible for nest finding, building and the welfare of the next generation. However, it is not uncommon to find several in close proximity to one another. In fact in some parts of the world their territories can be quite extensive even covering several acres if the conditions are right. Leafcutter bees like mason bees, can cause damage to property depending upon their numbers and where they choose to build their nests.

Life cycle

If you see neat segments cut out of the leaves of your roses or other shrubs, leafcutter bees are the likely culprits. Using their mandibles (mouthparts) they remove neat pieces of leaves or even flower petals in some instances, to construct and line their nests, overlapping the pieces collected to construct cigar-shaped cells in hollow spaces. They will nest in a variety of places, in the ground, under stones, in cavities in wood and stone, plant stems, and in dead wood. As many as 12 pieces of leaves are used by the leafcutter bee to form each cell. Smaller circular pieces of leaves are used to seal the cells and there are usually 6 to 10 cells per nest.

Before sealing the cell the female bee deposits a supply of pollen and nectar, then lays an egg on top, seals it up and goes on to build the next one. Each cell can take the bee around 6 to 8 hours in total to complete and seal off. Once she has sealed the last cell and has laid all her eggs the leafcutter bee has done her job and dies.

These bees are unusual in the insect world as each female lays on average only about 15 eggs. Compare that with a queen honey bee who can lay 100′s of thousands of eggs in her lifetime.The young over-winter in their cells as mature larvae and emerge as adult bees in late spring-early summer. The last egg laid is the first to hatch and these are usually males who then stay around on nearby flowers waiting for the females to emerge.

Pollination

Leaf cutter bees are considered to be very efficient pollinators and are being increasingly bred in the US and elsewhere as a substitute for failing honey bee colonies, in particular Megachile rotundata, the alfalfa leafcutter bee or lucerne leafcutter bee.This species was imported from Europe and has now been introduced into most major regions of the world, as it is an efficient pollinator of alfalfa, carrots and other vegetables.

Originally imported into North America to pollinate alfalfa, which honeybees avoid as the flowers need to be pried open to reach the pollen, these bees have become widespread. The alfalfa leafcutter bee is now managed intensively in North America and has become a multi million dollar business. They are also widely used in Russia and New Zealand and Australia where alfalfa is known locally as Lucerne.

It has been calculated that one alfalfa leafcutter bee can do the pollination job of 20 honey bees. As unlike honey bees they do not collect pollen in baskets on their legs but collect it in hairs on their abdomens and are therefore more likely to spread it about as they move around.

Stings

Leafcutter bees as with other solitary bees tend not to be as aggressive as honey bees and to a lesser extent bumble bees. Both the male and females are more likely to use their mandibles, however the female does have a stinger but will only use it if squeezed or caught beneath clothing. This bee’s sting is not as painful as a honey bee sting but is more like the bite of a mosquito in terms of pain level. Therefore unlike honey bees there is no necessity to wear bee suits when managing leafcutters.

By Maggie Roberts

Maggie is  professional writer and beekeeper, with a particular passion for sharing her knowledge of bees and their role in the natural world. If you would like more information and help to start beekeeping see www.beekeepingbeesandhoney.com .

Filed Under: Leafcutter Bees , Solitary Bees Tagged With: