Best time to see: mid Jul to mid Sep

Key facts

Large and usually solitary dragonfly, flying mid to late summer

Habitat: woodland ponds, lakes and canals; often breeds in park ponds and small garden pools

Common in lowland England and Wales, becoming scarcer further north

Recognition

Males are dark marked bright green, becoming blue at the tail; females are stouter and marked yellow and green

Males often hover low to inspect people before returning to their beat; body held horizontally in flight

Fly from July until October, usually solitary, preying on flying insects

Lifecycle

Females lay eggs in dead plants, logs or moss near water, usually alone, and they remain dormant over winter

Larvae hatch in spring and emerge about 15 months later, eating small invertebrates and, later on, tadpoles and small fish

Larvae leave the water at night and emerge as adults before dawn