Dragonflies and damselflies belong to the order of insects called Odonata, meaning ‘toothed jaws’. They are a very ancient group of four-winged insects and their ancestors were flying 320 million years ago, with wingspans of 75cm for the largest species. They need water to complete their lifecycle – habitats include ponds, lakes, streams, rivers, bog pools, and flushes and runnels in heathland.
Dragonflies are known as Anisoptera, meaning ‘different wings’, and Damselflies as Zygoptera, meaning ‘paired wings’. Dragonflies (Anisoptera) usually hold their wings apart when they are resting and their eyes meet in the middle. Their fore and hind wings are different shapes. Damseflies are generally smaller than dragonflies and are weaker fliers. They hold their wings together when they are resting and their eyes are spaced apart on either side of the head. Their fore and hind wings are the same shape. There are a few exceptions to these rules. There are just under 6,000 species of dragonflies and damselflies worldwide but only 45 of these occur in the UK. Rather confusingly, in the English language dragonflies and damselflies are collectively termed ‘Dragonflies’.
There are 15 species of Damselfly that have been recorded in Wales, including 1 very rare migrant, there have been 22 species of Dragonfly recorded in Wales, including 5 migrant species i.e. those not breeding regularly in Wales.
|Scientific name||English name||Cymraeg name|
Winter Damselfly (m)
Small Red Damselfly
Common Blue Damselfly
Small Red-eyed Damselfly
Scarce Blue-tailed Damselfly
Large Red Damselfly
Vagrant Emperor (m)
Lesser Emperor (m)
Yellow-winged Darter (m)
Red-veined Darter (m)
Vagrant Darter (m)
mursen y gaeaf
mursen lygatgoch fach
mursen las Penfro
mursen las asur
mursen las amrywiol
mursen las gyffredin
mursen lygatgoch fawr
mursen lygatgoch fach
mursen dinlas gyffredin
mursen dinlas fach
mursen fawr goch
gwas neidr blewog
gwas neidr y de
gwas neidr brown
gwas neidr glas
gwas neidr mudol
gwas neidr crwydrol
gwas neidr tindrwm
gwas neidr eurdorchog
gwas gwyrdd blewog
dubia picellwyr wynebwyn
picellwyr pedwar nod
gwäell asgell aur
gwäell wythïen goch
(m) = migrant species
The Welsh names are taken from the book 'Cyfres Enwau Creaduriaid a Phlanhigion: 3 - Gwyfynod, Glöynnod Byw A Gweision Neidr' edited by Duncan Brown, Twm Elias, Bruce Griffiths, Huw John Huws and Dafydd Lewis ISBN number 978-1-84527-259-3.
Part of the British Dragonfly Society (BDS) work in Wales has delivered conservation for one of Wales’s rarest species, the Southern Damselfly Coenagrion mercuriale. The Preseli SAC in Pembrokeshire is home to one of the Southern Damselfly’s two strongholds in the UK. It is thought that the UK populations make up a significant proportion of the worldwide population of this species. Because of its rarity and the importance of the population in the Preseli SAC, both the species and its habitat are afforded legal protection at a national and European level. In Wales it is a priority species under S7 of the Environment (Wales) Act. It is protected in law under Schedule 5 of the Wildlife and Countryside Act 1981 (as amended) and is listed as Endangered on the Odonata Red Data List. Not only is it rare and endangered in Britain, it is also listed as Near Threatened on the European Red List and protected by the European Community Habitats and Species Directive. Its presence is a primary reason for the Preseli’s being designated as a Special Area of Conservation (SAC). It is therefore of paramount importance that the species key breeding sites in Wales are preserved, enhanced and expanded wherever possible.
Southern Damselfly Coenagrion mercuriale is the smallest of the ‘blue damselflies’ where the males are bright blue with black markings and the females are duller. Males can be distinguished from those of similar species by the ‘mercury’ mark on segment two of the abdomen and the spear-shaped markings on other abdominal segments. Females are usually dull green with the abdomen mainly black above. They have a thistle shape at the top of the abdomen and a few blue divisions between the segments near the tip of the abdomen. Rarer blue-form females can occur. Both sexes have a small lobe on the rear edge of the pronotum.
The species is rather sedentary, rarely flying more than 50 metres from its emergence site. This makes the species very vulnerable especially as it has very specialised habitat requirements. In Pembrokeshire, good condition breeding sites are within heathland and are flushes and shallow streams that are ground water-fed . This ensures consistently mild water temperatures and permanently flowing water. The streams have a gravely or clayey bed with patches of organic detritus. The watercourses should be well vegetated, but with areas of open water. Emergent water plants that mark suitable habitat include Bogbean Menyanthes trifoliata, Marsh St John’s Wort Hypericum elodes, Bog Pondweed Potamogeton polygonifolius and Fool’s Watercress Apium nodiflorum. The species also requires areas of nearby shelter for the adults.
The Southern Damselfly was once more widespread in Pembrokeshire. Two of the three main populations have gone extinct, leaving small, scattered populations within and around the Preseli SAC which is also common ground. These are now vulnerable due to a large reduction in grazing, especially of larger stock. This lack of grazing has led to flushes becoming swamped and choked by adjacent vegetation, thereby making the habitat unsuitable for Southern Damselflies. Recent observations and several years worth of monitoring have shown that the population of Southern Damselfly in Pembrokeshire is declining and in many cases clinging on to the last fragments of habitat that are still suitable, but no longer ideal.
Recent changes in land management have put particular pressure on the existing populations in Pembrokeshire. The Southern Damselfly needs well-grazed and open vegetation beside small streams. It is also beneficial for the streams to have trampled margins and tussocks created by heavy grazing animals, like cattle or horses.
There are many constraints to achieving the correct grazing regimes for Southern Damselflies on common land. These constraints are due to economic, legal and cultural reasons. There are also many separate parties with an interest in common land, resulting in there being a number of individual issues to overcome before the practical problems can be considered and assessed. It is hoped that in future years we will be able to find a way to improve the grazing regime for the Southern Damselfly that is supported by and benefits all users of the common.
Since 2011, the BDS has been working with partners in Pembrokeshire to both preserve and create important habitat areas for the Southern Damselfly. Two of these projects, at Penlan and Pensarn Corner, have been supported by Environment Wales with funding from the Welsh Government and the other practical project at Brynberian (Glanyrafon Uchaf) and management plan have been made possible through funding from the Wales Biodiversity Partnership. Working in partnership with Natural Resources Wales (NRW - formerly CCW) and the Pembrokeshire Coast National Park Authority (PCNPA), British Dragonfly Society (BDS) staff and volunteers have created the ideal environment for the species at Penlan and saved a valuable area of habitat at Pensarn Corner. These projects have also been supported by the land owner and grazers. The management plan now informs and guides all the practical work carried out for the Southern Damselfly in this area.
This project was funded by Environment Wales. It created new Southern Damselfly habitat at a site owned and managed by PCNPA. The practical work involved creating new flushes, pools and streams from existing springs on the site. The site is near to 3 existing Southern Damselfly breeding sites. It has also been managed through grazing since the practical work was carried out.
For more information about the project click here
This practical conservation project was made possible through funding from the Wales Biodiversity Partnership. This flush used to be a breeding site for Southern Damselflies. Habitat degradation due to lack of grazing has resulted in the flush becoming piped (roofed over with vegetation and turf). The work involved manipulation of three streams using a variety of techniques to open up the channel where it had become piped. This created shallow, wide watercourses where Southern Damselfly habitat will be able to develop. Since the habitat has been restored, Southern Damselflies have been recorded at the site.
For more information about the project click here
This practical conservation project was made possible through funding from Environment Wales. It involved a small section of common land on the northern edge of the Preseli SAC which supports several rare dragonfly species including the Southern Damselfly. The area was at risk because access to the Common was becoming difficult and the streams were in danger of becoming choked up. The work improved access across the area for both people and livestock, whilst at the same time preserving and enhancing habitat conditions for the rare dragonflies the area supports. This was done by putting a piped bund in place. This will maintain water levels whilst allowing water to flow through the bund. In turn, this will prevent the wet heath from drying out, even if water levels drop, and dragonfly habitat will be maintained.
For more information about the project click here
There are three stages in the life-cycle of all Dragonflies. The egg hatches into the larva (also known as a nymph), which moults up to 18 times before emerging as an adult. Unlike other more recently evolved insects, there is no pupal stage.
Hawker dragonflies and damselflies lay their eggs directly into plant material in the water or on moss, roots or into mud near to the water. Chaser, skimmer,darter and emerald dragonflies lay their eggs directly into the water by hovering and flicking their abdomen over the water whilst releasing eggs.
When the female is egg-laying, male damselflies, chasers, skimmers and darters guard the females with which they have just mated. Mate guarding is done by either staying joined ‘in tandem’ with the female whilst she is laying eggs, or staying close to the female whilst she is egg-laying and chasing off any rival males.
After the eggs have been laid, some hatch within 2-5 weeks and others laid late in the year enter a diapause (like hibernation) over winter. Dragonflies live underwater as larvae for between 3 months and 5 years. During this time they will undergo between 8 and 18 moults to grow.
Both larval and adult dragonflies are ferocious, opportunistic predators. As larvae their prey includes insect larvae, crustaceans, worms, snails, leeches, tadpoles and small fish. Different species of larvae adopt different hunting strategies; some will actively hunt prey and are usually coloured to be camouflaged in aquatic plants, while others are ambush hunters, and are darker allowing them to be camouflaged in the mud and detritus where they hide waiting for prey to pass.
Once they are fully grown and weather conditions are suitable, larvae will emerge as adult dragonflies or damselflies. In the UK this occurs between April and September, depending on species. Emergence is a risky process. Adverse weather conditions can result in failed emergence and the dragonfly dying - a newly emerged dragonfly is very vulnerable to predation until it becomes fully active. When it is ready to emerge, the larva chooses a suitable support to climb up - this may be an emergent plant stem, rock or pond liner. The larval skin splits creating a hole in the back (thorax) and the dragonfly hauls its head and thorax out of this hole. It needs to wait for its legs to harden before pulling itself fully out of the larval skin (exuvia). The newly emerged dragonfly will then hold on to the empty larval skin or plant stem while it pumps up its abdomen (body) and wings by redistributing its body fluid. The dragonfly then waits for its wings to harden sufficiently for it to fly.
Initially the adult will live away from water bodies as it fully develops its colours and becomes sexually mature. This takes around a week, andit will spend this time feeding. Adult dragonflies eat a wide variety of insect prey including mosquitoes, midges and flies, but they will also eat larger prey such as butterflies and other dragonflies and damselflies.
On maturing, males will return to water bodies where most species are territorial and defend areas of suitable breeding habitat. Females will only return to the water bodies when they are ready to mate, to avoid being harassed by males. Before they mate, males need to transfer their sperm from segment nine of the abdomen to secondary genitalia below their 2nd abdominal segment; this is usually done after grabbing a female, but can be before. Male dragonflies use their tail (anal) appendages to grasp females; in dragonflies (Anisoptera), the males grasp round the female’s eyes, but in damselflies, males grasp round the female’s neck. Once the male has grasped the female, they are ‘in tandem’, and can fly quite well joined together, If she wants to mate, the female will bring the end of her abdomen up to the male’s secondary genitalia for sperm transfer, creating a ‘heart’ shape - this is the copulatory position, also known as the “wheel”. After mating, the female will lay her eggs and the life cycle starts again. In the UK most of the life cycle is spent as larvae underwater; adult dragonflies can live for up to 8 weeks, but on average in Britain they live only 1 – 2 weeks.
Text provided by Claire Install BDS Officer Wales
There are many complicated issues surrounding the management of Southern Damselfly habitat in and around the Preseli SAC. The Southern Damselfly is a primary reason for the designation of the SAC so its habitat needs to be maintained as part of European law. The management document was produced to try to overcome these and provide guidance for future work. The management document is entitled ' An Overview of the Management Requirements of the Southern Damselfly (Coenagrion mercuriale-Charpentier) with Recommendations and Suggested Methodology for Habitat Improvement within and near to the Preseli SAC'
The production of the management document was made possible through funding from the Wales Biodiversity Partnership.