Wool carder bee

How to recognise it

Stout and wasp-like, black with rows of bright yellow spots down the sides of the abdomen, and a fringe of pale hair. Females carry pollen dry on the underside of the abdomen. Males are noticeably bigger — up to about 1.7 times the female's size — and carry three to five sharp spines at the abdomen tip.

• Yellow-spotted, wasp-like patterning on a bee-shaped body — the commonest cause of it being reported as a wasp.
• Females seen scraping hairs off woolly-leaved plants, particularly lamb's ear, and flying off with a visible ball of fluff.
• Males hovering and darting aggressively over a flower patch, chasing off other bees. Almost no other bee does this.
• Male larger than female, which reverses the normal pattern in bees.

Body length 11–17 mm (typically 14 mm).

Biology

Social organisation

Solitary

Each female builds and provisions her own nest with no workers and no caste. Most of the world's bee species.

Nesting

Existing cavities and tubes; Hollow stems and plant cavities

Uses existing cavities — hollow stems, holes in wood and walls, bee hotels — and lines and separates the cells with plant hairs scraped from woolly-leaved plants. The female bites the hairs free, rolls them into a ball under her body, and carries the bundle back in flight, which is the behaviour the name records.

Carries pollen

Scopa on the underside of the abdomen

On the wing

June to August

A summer bee, appearing well after the mason bees have finished.

Lifecycle

1. 1Emergence and territory establishmentMales emerge and immediately claim a patch of suitable flowers, defending it against all comers for as long as they can hold it. Access to the patch is access to the females that feed there.June onwards.
2. 2NestingFemales collect plant hairs and pollen and provision cells in a cavity, working alone through the summer.Six to eight weeks.
3. 3OverwinteringThe larva completes its development and overwinters in the cell as a prepupa, emerging the following summer.Roughly ten months.

Where it lives and what it does

Habitat

Gardens above all, because gardens contain both the woolly plants it needs for nest material and the tubular flowers it prefers to feed from. Also brownfield sites, hedgerows and rough ground.

Distribution

Native to Europe, North Africa and western Asia. Introduced and now widespread in North America, where it was first recorded in New York State in 1963, and subsequently in South America, New Zealand and the Canary Islands — one of the most widely established introduced bees in the world after the honey bee.

Behaviour

The male's territoriality is the defining behaviour and it is genuinely unusual: he patrols a flower patch continuously, hovers, and rams intruders in flight, sometimes grasping them and using his abdominal spines. Larger males hold better patches and mate more. Females, in contrast, go about their business quietly and are far less often noticed.

Pollination role

A competent pollinator of the plants it favours, particularly legumes and mints, and carrying pollen dry on the abdomen means it transfers a good proportion of what it collects. The complication is the male: by excluding other bees from a flower patch he reduces visitation by species that may pollinate those plants better, and in its introduced range this competition is the main concern about the species.

Moderate as an individual pollinator, with a net effect complicated by male territorial exclusion of other bees.

What it forages on

Strongly favours the mint and pea families — lamb's ear, woundworts, catmint, salvias, vetches and clovers. It feeds and gathers nest material from overlapping but different plants, which is why a garden with both suits it so well.

Honey

Produces no honey

None. Solitary, with a pollen loaf per cell and no colony to carry through a winter.

Relationship with people

How people interact with it

A garden bee more than a wild one, and one of the few solitary bees whose behaviour is dramatic enough to be noticed. It is also a reminder that bees can be introduced species with ecological costs — the assumption that any bee is a good bee does not survive contact with an introduced territorial competitor.

Conservation

Not of conservation concern in its native range and increasing. In North America and South America it is an established non-native whose effect on native bees is the subject of ongoing work rather than a settled question.