Sussex Dragonfly Group

Emperor Dragonfly
Anax imperator Leach, 1815
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Suborder: Anisoptera
Family: Aeshnidae

Emperor Dragonfly
Anax imperator

Suborder: Anisoptera
Family: Aeshnidae

The Emperor is our largest dragonfly, with broad wings and a robust body. The males have a green thorax and bright blue abdomen with a black dorsal stripe running the entire length. Females have a mainly green thorax and abdomen. Very aptly named, this species aggressively dominates still-water habitats, from small garden ponds and dew ponds, to large lakes and reservoirs. Aerial ‘dog-fights’ between rival males are an impressive spectacle.

Anax imperator
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male in flight
Photo: Simon Linington
Anax imperator
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ovipositing female
Photo: Simon Linington
Anax imperator
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ovipositing female
Photo: Simon Linington
Anax imperator
4 / 9
male
Photo: Simon Linington
Anax imperator
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male
Photo: Simon Linington
Anax imperator
6 / 9
female
Photo: David Sadler
Anax imperator
7 / 9
female
Photo: David Sadler
Anax imperator
8 / 9
male
Photo: David Sadler
Anax imperator
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male
Photo: David Sadler

More images

National status
Widespread in southern England and southern Wales; extending its range northwards.

Status in Sussex
Common all over the county wherever there is suitable habitat. In the decade to 2020, there appears to have been an increase in records on the Wealden Greensand and along the southern Arun with a decrease from Ashdown.

Distribution at 1km scale

Anax imperator distribution (all)
Anax imperator distribution pre 1980
Anax imperator distribution 1980 - 1989
Anax imperator distribution 1990 - 1999
Anax imperator distribution 2000 - 2009
Anax imperator distribution 2010 - 2019
Anax imperator distribution 2010 on

Historical records
Dannreuther (1939) regarded this as a “rather local southern species” but most other authors have suggested that this has always been a common insect in Sussex. Chelmick (1979) commented that in the south west of the county it was less common than elsewhere but this appears to have changed.

Flight times
Late May - early September. Unlike for many other Sussex Odonata, the flight time of this species doesn’t appear to have expanded in recent decades.

Phenology (adult)

Anax imperator phenology (all)
Anax imperator phenology pre 1980
Anax imperator phenology 1980 - 1989
Anax imperator phenology 1990 - 1999
Anax imperator phenology 2000 - 2009
Anax imperator phenology 2010 - 2019
Anax imperator phenology 2010 on
Anax imperator habitat
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Emperor Dragonfly habitat at Woods Mill
Photo: Simon Linington

Habitat
Still waters like ponds, lakes, gravel pits and canals.

Conservation
As an early coloniser of new ponds, and perhaps our most magnificent dragonfly, the Emperor provides a great incentive to creating new wetland habitats.

Similar species
See Southern Hawker for a discussion of potential confusion species.

The Emperor is our largest dragonfly, with broad wings and a robust body. The males have a green thorax and bright blue abdomen with a black dorsal stripe running the entire length. Females have a mainly green thorax and abdomen. Very aptly named, this species aggressively dominates still-water habitats, from small garden ponds and dew ponds, to large lakes and reservoirs. Aerial ‘dog-fights’ between rival males are an impressive spectacle.

Anax imperator
1 / 9
male in flight
Photo: Simon Linington
Anax imperator
2 / 9
ovipositing female
Photo: Simon Linington
Anax imperator
3 / 9
ovipositing female
Photo: Simon Linington
Anax imperator
4 / 9
male
Photo: Simon Linington
Anax imperator
5 / 9
male
Photo: Simon Linington
Anax imperator
6 / 9
female
Photo: David Sadler
Anax imperator
7 / 9
female
Photo: David Sadler
Anax imperator
8 / 9
male
Photo: David Sadler
Anax imperator
9 / 9
male
Photo: David Sadler

National status
Widespread in southern England and southern Wales; extending its range northwards.

Status in Sussex
Common all over the county wherever there is suitable habitat. In the decade to 2020, there appears to have been an increase in records on the Wealden Greensand and along the southern Arun with a decrease from Ashdown.

Distribution at 1km scale

Anax imperator distribution (all)
Anax imperator distribution bre 1980
Anax imperator distribution 1980 - 1989
Anax imperator distribution 1990 - 1999
Anax imperator distribution 2000 - 2009
Anax imperator distribution 2010 - 2019
Anax imperator distribution 2020 on

Historical records
Dannreuther (1939) regarded this as a “rather local southern species” but most other authors have suggested that this has always been a common insect in Sussex. Chelmick (1979) commented that in the south west of the county it was less common than elsewhere but this appears to have changed.

Flight times
Late May - early September. Unlike for many other Sussex Odonata, the flight time of this species doesn’t appear to have expanded in recent decades.

Phenology (adult)

Anax imperator phenology (all)
Anax imperator phenology pre 1980
Anax imperator phenology 1980 - 1989
Anax imperator phenology 1990 - 1999
Anax imperator phenology 2000 - 2009
Anax imperator phenology 2010 - 2019
Anax imperator phenology 2020 on
Anax imperator habitat
1 / 1
Emperor Dragonfly habitat at Woods Mill
Photo: Simon Linington

Habitat
Still waters like ponds, lakes, gravel pits and canals.

Conservation
As an early coloniser of new ponds, and perhaps our most magnificent dragonfly, the Emperor provides a great incentive to creating new wetland habitats.

Similar species
See Southern Hawker for a discussion of potential confusion species.