Blue-tailed Damselfly
Ischnura elegans
Tap image to enlarge · Wikimedia Commons
Overview
The Blue-tailed Damselfly is one of the most tolerant of all damselflies — it can breed in heavily polluted or brackish water where other Odonata cannot survive. This makes it one of the most widespread and abundant species on the Sefton Coast. The male has a distinctive blue tail tip (segment 8) that glows electric blue in the right light. Females come in several colour forms — violet, pale green, buff or blue. Very approachable at rest.
At a Glance
| Order | Odonata |
| Family | Coenagrionidae |
| Habitat | Dune slack pond · Marsh ditch · Any standing or slow freshwater |
| Diet | Small flying insects |
| UK population | Very common throughout Britain; one of the most abundant damselflies |
| Sefton Coast | Abundant at any suitable water body on the Sefton Coast |
| Conservation | UK Green List |
Where to See It
Any dune slack pond, ditch or open water at Ainsdale NNR and Marshside RSPB. Very tolerant of poor water quality.
Identification
Slender damselfly. Male: dark body with brilliant blue segment 8 near tail tip — the key feature. Black and blue/green thorax. Female: various colour forms (pinkish-violet, blue, green or buff) — all have the blue/coloured segment 8 pattern. Bronze-green thorax with pale stripes.
Viewing & Photography Tips
Check any open water on the Sefton Coast from May. The bright blue tail tip of the male is visible at quite close range. Much more tolerant of disturbed water than other damselflies.
Conservation Status
UK Green List
This species has a favourable conservation status in the UK and remains an important part of Sefton Coast biodiversity.
Frequently Asked Questions
Why do female Blue-tailed Damselflies come in so many colour forms?
Female Blue-tailed Damselflies show remarkable colour polymorphism — up to five distinct colour forms in some populations. Research suggests that some female colour forms are more successful at avoiding male harassment (males harass females of the most common colour more, so rarer colours gain protection by being unusual). This frequency-dependent selection may maintain the polymorphism.
Related Species
Plan your visit to the Sefton Coast
Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.