Sussex Dragonfly Group

Norfolk Hawker (Green-eyed Hawker)
Aeshna isoceles (Müller, 1767)
Synonym: Anaciaeschna isosceles
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Suborder: Anisoptera
Family: Aeshnidae

Norfolk Hawker
(Green-eyed Hawker)
Aeshna isoceles
Synonym: Anaciaeschna isosceles

Suborder: Anisoptera
Family: Aeshnidae

Otherwise known as the Green-eyed Hawker, this is a recent vagrant to Sussex with just one record up to 2020. There was a small arrival in 2021 with potential colonisation along the Chichester Canal. Since then, there has been a dramatic expansion, particularly on Pevensey Levels.

Aeshna isoceles
1 / 3
female
Photo: David Sadler
Aeshna isoceles
2 / 3
male
Photo: David Sadler
Aeshna isoceles
3 / 3
male
Photo: David Sadler

More images

National status
As its name suggests, the Norfolk Hawker’s breeding area is currently restricted to parts of East Anglia namely the Broadlands of Norfolk and north-east Suffolk. There are scattered records elsewhere in England including from the south in Kent, Hampshire and Devon. It is protected under the Wildlife and Countryside Act.

Status in Sussex
The first record was one on 5 July 2019 at Medmerry RSPB Reserve found by John Arnott and photographed by Christian Hance. There was a small arrival in 2021 with seven or more along the Chichester Canal and records elsewhere from Amberley Wild Brooks, West Rise Marsh and Pevensey Levels. The colony at Chichester Canal was still present in 2022 and reports included 10 there on 15 June. Since then, there has been further range expansion and consolidation with significant numbers at the Chichester Canal, Pevensey Levels and West Rise Marsh. It is uncertain whether the Sussex population originates from eastern England or from the Continent.

Distribution at 1km scale

Aeshna isoceles distribution (all)
Aeshna isoceles distribution pre 1980
Aeshna isoceles distribution 1980 - 1989
Aeshna isoceles distribution 1990 - 1999
Aeshna isoceles distribution 2000 - 2009
Aeshna isoceles distribution 2010 - 2019
Aeshna isoceles distribution 2010 on

Flight times
May - August ( BDS website)

Phenology (adult)

Aeshna isoceles phenology all records
Aeshna isoceles phenology pre 1980
Aeshna isoceles phenology 1980 - 1989
Aeshna isoceles phenology 1990 - 1999
Aeshna isoceles phenology 2000 - 2009
Aeshna isoceles phenology 2010 - 2019
Aeshna isoceles phenology 2010 on

Habitat
Fens and grazing marshes that are relatively free of water pollution. Presence of Water Soldier (Stratiotes aloides) seems to be one important prerequisite for breeding.

Similar species
The bright green eyes and brown body of this dragonfly distinguish it from all but the immature Southern Migrant Hawker which has duller green eyes and a more gingery-brown abdomen with yellow markings along its length. The Brown Hawker has distinctly brown wings.

Otherwise known as the Green-eyed Hawker, this is a recent vagrant to Sussex with just one record up to 2020. There was a small arrival in 2021 with potential colonisation along the Chichester Canal. Since then, there has been a dramatic expansion, particularly on Pevensey Levels.

Aeshna isoceles
1 / 3
female
Photo: David Sadler
Aeshna isoceles
2 / 3
male
Photo: David Sadler
Aeshna isoceles
3 / 3
male
Photo: David Sadler

National status
As its name suggests, the Norfolk Hawker’s breeding area is currently restricted to parts of East Anglia namely the Broadlands of Norfolk and north-east Suffolk. There are scattered records elsewhere in England including from the south in Kent, Hampshire and Devon. It is protected under the Wildlife and Countryside Act.

Status in Sussex
The first record was one on 5 July 2019 at Medmerry RSPB Reserve found by John Arnott and photographed by Christian Hance. There was a small arrival in 2021 with seven or more along the Chichester Canal and records elsewhere from Amberley Wild Brooks, West Rise Marsh and Pevensey Levels. The colony at Chichester Canal was still present in 2022 and reports included 10 there on 15 June. Since then, there has been further range expansion and consolidation with significant numbers at the Chichester Canal, Pevensey Levels and West Rise Marsh. It is uncertain whether the Sussex population originates from eastern England or from the Continent.

Distribution at 1km scale

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

Flight times
May - August ( BDS website)

Phenology (adult)

Aeshna isoceles phenology (all)
Aeshna isoceles phenology pre 1980
Aeshna isoceles phenology 1980 - 1989
Aeshna isoceles phenology 1990 - 1999
Aeshna isoceles phenology 2000 - 2009
Aeshna isoceles phenology 2010 - 2019
Aeshna isoceles phenology 2020 on

Habitat
Fens and grazing marshes that are relatively free of water pollution. Presence of Water Soldier (Stratiotes aloides) seems to be one important prerequisite for breeding.

Similar species
The bright green eyes and brown body of this dragonfly distinguish it from all but the immature Southern Migrant Hawker which has duller green eyes and a more gingery-brown abdomen with yellow markings along its length. The Brown Hawker has distinctly brown wings.