Aeshna juncea - Common Hawker

Phylum: Arthropoda - Class: Insecta - Order: Odonata - Family: Aeschnidae

Description

The Common Hawker is a very large (typically 7.5cm long), fast-flying dragonfly with yellowish costa (leading edges of wings).

The male (above) is predominantly black with paired pale blue spots and yellow flecks along its body; its eyes are dark blue, and there are pale yellow-and-blue patches on its thorax.

Most females have browner bodies with yellowish spots and their eyes are brown rather than blue; however, the so-called 'blue' female form also occurs, and an example is shown above.

Above: Closeup of a female Common Hawker, blue form

Distribution

The Common Hawker is common in Ireland, western England, Wales and Scotland; it is rarely if ever seen in the south and east of England.

Habitat

This dragonfly favours upland acidic bogs and heathland, where it breeds in permanent pools and lakes; however, this species has also been recorded quite often from garden ponds in neutral- or acid-soil areas.

Lifecycle

Common Hawkers can be seen on the wing from Late June through to October. The female lays her eggs in summer and early autumn, stabbing her ovipositor into submerged marginal vegetation. The eggs lie dormant through the winter and then hatch in the following spring.

Common Hawker nymphs (naiads) take two, three or sometimes four years to reach maturity, during which time they feed on small invertebrates including the nymphs and larvae of other aquatic insects as well as tadpoles and, when they can catch them, newborn newts (known as efts).

Acknowledgements

This page includes pictures kindly contributed by Betty and Tony Rackham and by James Wainscoat.