Life Cycle of Bees

Identification 

There are an estimated 4000 species of bees considered to be native to North America, with the identification of each species being a complex process which is best left to the specialists of the field. Native bees are classified into main family groups that are further divided into subgroups. Groupings are based on distinguishing physical features and nesting or foraging behavior differences.

This Bee friendly guide will use the bold type names shown below for each of the main bee family groups and subgroups. The six main family groups of native bees are as follows:

(Apidae) –  honeybeesbumble bees and small carpenter bees

(Megachilidae) – orchard bees/mason bees, leafcutter bees, resin bees and carder bees

(Andrenidae) – mining bees

(Halictidae) –  green bees, sweat bees and orchid bees

(Colletidae) – plasterer bees

(Melittidae) – oil bees

Native bees have various nesting behaviors that are also used to identify their species. There are both ground- and cavity-nesting types of bees, and each of these types can be further classified into solitary, communal and social types.

The most numerous of our indigenous types are the ground-nesting bees, which belong to all of the main family groups, and are commonly found throughout most areas of North America. Ground-nesting bees have many complex nesting systems adapted to various soil types or ground conditions, and can be found in a wide range of landscapes and gardens.

Cavity-nesting bees use existing tunnels or chambers found within their habitats, such as tunnels bored out of wood by other insects or dens and nests created by other animals. Cavity-nesting bees are not usually equipped to do the tunnel boring or chamber building themselves, so they take advantage of what they can find within their local habitats and are often discovered making use of man-made structures and artificial nest boxes.

Life Cycle 

Since bees are insects they all have exoskeletons, three body sections (unlike spiders), and six to ten legs. Bees have four basic life stages that are common to all insect types. These include the egg, larval, pupal, and adult stages.

Many of our local indigenous bees are classified as having solitary life cycles and sharing a similar system of reproduction that follows a variable timetable throughout the year depending on the bee species. A typical example of a solitary bee life cycle is that of the commonly known blue orchard bee, Osmia lignaria, which begins its active adult life stage in late-March to mid-April each year when it emerges from its overwintering cocoon. The male orchard bee emerges from his nesting tunnel before the female, and begins to forage for nectar to gain strength and energy for mating. The female orchard bee emerges from her nesting tunnel and quickly mates with the short-lived male, who expires after mating is complete. The fertile female then forages for available nectar, which she consumes for energy, and local pollen, which she uses to stock her chosen nesting site with a supply of food for each egg she will lay. She deposits between 4-30 eggs into her nesting tunnel during her six- to eight-week adult life cycle. Each deposited egg, which has been laid in its own chamber, soon hatches into a small larva. After consuming the food stores left by its parent, the larva begins to spin a cocoon around itself. Once finished, it metamorphoses into an adult bee that remains dormant until the following spring.
copy of osmia_life_cycle_chart