Name
Aeshna isosceles (Muller, 1767)
Family:
Aeshnidae
Status in Britain and Ireland:
GB Red List Endangered & Wildlife & Countryside Act 1981 (Sched 5).
Until recently rarely seen away from a few sites in Norfolk Broads and NE Suffolk. Range now changing dramatically with individuals seen in a range of locations in UK. Status will likely be changed to reflect this.
Local Status:
Rare
Size:
Overall body length 62-67mm
Hindwing length 39-45mm
Flight period:
June to July
Photograph © Santiago Monteagudo Campossmall
Male Norfolk Hawker
A large brown hawker with brown body, clear wings and striking green eyes. The brown abdomen has no spots of colour down the side, but has a distinctive yellow triangle on the dorsal surface of segment 2. The brown thorax has no really noticeable antehumeral stripes, but 2 broad yellow side stripes clearly visible in flight.
Photograph © D. Smallshire
Female Norfolk Hawker
Similar to the male with brown body, clear wings and green eyes and also bearing the yellow triangle on top of abdominal segment 2. The 2 yellow side stripes on side of thorax may be less prominent in female.
Similar Species
Common and widespread Brown Hawker. It is far more likely that you will see Brown Hawker than Norfolk Hawker in Shropshire. It is larger with brown eyes and noticeably brown wings and no yellow triangle on segment 2 of the abdomen. Dots of blue (or sometimes yellow in female) are present down the sides of the abdomen. Norfolk Hawker flies slightly earlier in the year than Brown Hawker so if you see a large brown insect in June take a good look!
Behaviour
Males known to be territorial as they patrol suitable habitat. When 3 individuals were observed in Shropshire however they seemed very ‘tolerant’ of each other despite being in relatively close proximity. They also frequently perched on the vegetation. Much has been written regarding behaviour witnessed in Norfolk and Suffolk so it will be interesting to see how this species behaves as it expands it’s range.
Habitat
Previously thought to be limited to areas of Norfolk and Suffolk where the plant Water Soldier was abundant. Recent changes in range however have seen this species recorded in many areas without Water Soldier. In mainland Europe described as locally common and seen at ditches, lakes, ponds, canals and even sometimes at slow flowing water.
Shropshire Distribution
Only recorded once in 2024 when 3 individuals (1 male and 1 mating pair) were seen at a private site Isle Pool near Shrewsbury in early June. This may be a chance one-off encounter or may be the sign of things to come…
Shropshire Distribution Map (SEDN)
© Crown copyright 2016 OS 100049049
Where to see in Shropshire
Early days so keep your eyes open for anything brown in early summer!