Dragonflies and damselflies are some of our oldest insects whose ancestors flew the earth over 300 million years ago. They are beautiful aerial jewels with stunning colours, fascinating behaviour and majestic powers of flight.
There is extensive folklore about dragonflies dating back many centuries. In many countries they are revered as symbols of strength, regeneration, and pure water; whilst in others they are feared as shamanistic creatures with supernatural powers or symbolise instability and weakness. Dragonflies are actually harmless to humans as they have no sting and will not attack. In fact, as well as being an integral part of wetland ecosystems, they can be of great benefit to us all as unrivalled indicators of the health of aquatic environments.
The size and beauty of dragonflies make them especially valuable subjects for research on insect behaviour and ecology. Dragonflies have aquatic larvae, which generally rely on good quality water. Consequently they can be used to make rapid assessments of water quality and indicate a healthy ecosystem.
Dragonflies are worthy of conservation in their own right, but their requirements of clean water and a mosaic of terrestrial and aquatic habitats mean that, if they are conserved, so are many other organisms. They can be used as flagships for the insect world as a whole.
- 1 Dragon or Damsel?
- 2 How they breed and feed…
- 3 Dragonflies and damselflies in Scotland
- 4 First encounters – the widespread species
- 5 Important habitats for dragonflies and damselflies in Scotland
- 6 Vagrants, migrants and colonists
- 7 Threats
- 8 Red List and Biodiversity Action Plan (BAP)
- 9 Conservation –how you can help dragonflies and damselflies
- 10 Finding out more about dragonflies
- 11 Sanasan Gàidhlig – Gaidhlig Glossary
Dragon or Damsel?
Dragonflies and damselflies belong to a group (or “order”) of insects known as Odonata. Within this order, there are two main types (or “sub-orders”): damselflies (Zygoptera) and the true dragonflies (Anisoptera).
Damselflies are generally small, delicate insects with a weak flight. Their wings all have the same size and shape. Their eyes are widely separated and positioned on either side of the head. When at rest, they hold their wings closed along their abdomen – with the exception of Emerald damselflies (Lestes species) that hold them partly open.
True dragonflies are usually larger, more robust insects and are fast, powerful fliers. Their hindwings are broader than their forewings. They also have multi-facetted eyes, but these are much larger, occupy most of the head and are very close to one another, often touching. When perched, they hold their wings opened out flat.
How they breed and feed…
Dragonflies and damselflies are beautifully adapted for flight, having powerful muscles directing their four wings independently from one another. They are incredibly agile and manoeuvrable insects, able to hover, glide, fly forwards, backwards and sideways. They can also change their direction and speed of flight very rapidly.
As with all insects, their bodies are made of three basic parts: the head with multi-faceted eyes, the thorax to which the four wings and six legs are attached, and the abdomen with its ten segments.
Dragonflies and damselflies have a fascinating life history. Most of their life is spent underwater, first as an egg and then as a larva (or nymph) and they have a comparatively short adult life, being “on the wing” for a few weeks only.
For most species the whole process takes one or two years, and it begins with an egg. Eggs are laid in the vegetation, mud, or directly in the water of rivers, ponds, lochs. After a few weeks or months, depending on the species, the eggs eventually hatch out into larvae (or nymphs). The length of time spent as a larva underwater depends greatly on the temperature and availability of food. The larvae shed their skins many times to grow to full size, and developing ‘wing buds’ can be seen as they near maturity. Most damselflies take about a year to reach adulthood, whereas larger dragonflies may take two or more years.
When fully grown, the larva climbs out of the water onto a leaf, twig or stem, and begins its “emergence”. Its skin splits behind the head and on top of the thorax. With a slight struggle, the young adult will emerge out of the old larval skin, which is left behind. The transformation from underwater larva to winged adult is a vulnerable stage and takes place over a few hours. Soon after emergence, young adults with their pale colouration and shiny wings tend to leave the water body and will not return until they are ready to mate. The delicate, empty larval cases left behind, called “exuviae”, can be identified to species level just like larvae themselves, and constitute the ultimate proof that a given species is breeding at a site.
Once the young adults have matured and gained their full colours, male and female are ready to mate. Mating, depending on the species involved, takes place in the air, or on the ground, or amongst reeds or high up in the branches of a tree. Males use claspers (or “anal appendages”) at the end of their abdomen to grab females just behind the head. When ready, the female curves her body forward so that her reproductive organs reach those of the male. This forms the “wheel” or “heart” position, which is held from a few seconds to several hours depending upon the species.
After copulation, the pair is still perfectly capable of flying when linked or “in tandem”. The females of some species lay their eggs while still in tandem with the male. Others may separate after mating and the female is either left to lay her eggs alone or guarded by the male flying in close proximity, protecting her from disturbance by rival males. Some species deposit their eggs directly into the water, while others insert each individual egg into leaves, stalks or rotting wood floating on the water’s surface. The females of some damselfly species can even submerge themselves totally to lay their eggs into water plants. The eggs eventually hatch and the life cycle starts all over again.
Predators and Prey
Dragonflies and damselflies are voracious carnivores. When hunting for food, adults will take any flying insects they can catch, such as flies, midges and mosquitoes. The larger species will also eat butterflies, moths and occasionally smaller dragonflies or damselflies! Adults use their excellent eyesight to detect prey. In flight, they hold their bristly legs in a basket shape to scoop up and then firmly grasp their targets before eating their catch.
The larvae of all British dragonflies and damselflies are fierce underwater predators. They catch and consume anything which is smaller than they are, either by careful stalking or ambush. Prey may include bloodworms, water fleas, tadpoles and the larvae of mosquitoes or other aquatic insects. The larger dragonfly larvae may even catch and eat small fish! Dragonfly larvae have a remarkable tool at their disposal when hunting prey: their lower lip is modified into a long, hinged jaw terminating in two sharp, hook-like mandibles. This is known as the “mask”. When a prey is in sight, the mask is thrust forward and the prey instantly impaled on the hooks, then drawn back to the mouth and eaten. The shape of the mask can vary greatly between species and is an important feature in larval identification.
Among the species that catch and eat adult dragonflies and damselflies are birds (like the hobby); spiders, as many adults get caught in webs; frogs; and larger species of dragonflies. In the larval stage, their predators include fish, frogs, toads and newts, wildfowl, as well as other aquatic invertebrates such as water scorpions, diving beetles.
Dragonflies and damselflies in Scotland
Some 23 species are currently breeding residents, though some are very uncommon. This compares with just over 40 breeding species for the UK as a whole. The highest numbers of species in Scotland are to be found in the south, and on part of the west coast. Worldwide they are most abundant in the tropics. Despite its northerly location, Scotland is home to a number of these fascinating insects that are either rare or do not occur anywhere else in the British Isles. They include some that are restricted to cool, and even sub-arctic, climates. Their diversity is reflected in the many superb dragonfly habitats of the region – which include ancient forests, Sphagnum bogs and runnels, loch-studded moorlands, woodland streams, lowland, reed-fringed pools and marshes. Scotland is also a region of climatic contrasts. The west is heavily influenced by the Gulf Stream and is the recipient of prevailing weather systems from the Atlantic. The south-facing coast of Galloway is warm, and sheltered by the Irish Sea. On the east side of the country the cooler influences of the North Sea and continental weather are felt. This combined with the mountainous terrain of the Highlands and a north-to-south spread of over 600km (including the Northern Isles), gives an exceptional range of environmental conditions. How this effects their distribution and ecology is one of the many attractions of studying dragonflies and damselflies in Scotland.
What’s in a name?
As mentioned earlier, dragonflies and damselflies are the two main sub-divisions of a single, very distinctive group of insects that scientists refer to as Odonata. The name refers to the powerful jaws of both adult and larval stages. Confusingly, the expression ‘dragonfly’ is also often used for members of the Odonata as a whole. Here we leave the terms ‘dragonfly’ and ‘damselfly’ to their more specific meanings.
As well as their scientific Latin names, all Odonata now have well-established English-language names. Perhaps surprisingly for such conspicuous creatures, these are of quite recent origin, almost no species having been given a special name in the more distant past, in either England or Scotland. ‘Devil’s darning needles’ and ‘horse-stingers’ are widespread, and rather derogatory, colloquial titles used to characterise the group as a whole. The most widely accepted modern English names remain those listed by the British Dragonfly Society and it is these we have used throughout this publication.
In Gaelic, dragonflies have a variety of names which are similarly suggestive of superstitious distrust – perhaps inspired by the larger, fast-moving, highly coloured species:
- Ceann-nathrach [head of snake]
- Cuileag-lasrach [blazing fly]
- Damhan-nathrach [spider-snake]
- Tarb(an)-nathrach [bull-snake]
- Tarbh-nathair-neimh [venomous bull-serpent]
Cuileag-nan-cruinneag [fly of the damsel] seems to suggest that the smaller, more delicate damselflies were not thought to be so fearsome. Modern Irish Gaelic names have been developed and are listed in the species table. In Scotland every pool or lake, almost regardless of size, is a ‘loch’ or a ‘lochan’– a Gaelic word which appears on the map right down to the border with England. (The term is also used for narrow inlets of the sea).
Dragonflies and damselflies recorded from Scotland
All the species that have been found in Scotland, including extreme rarities, are listed below. Their status since 1900 is indicated as follows: black text: established resident species; blue: rare migrant or vagrant only; red: species moving north – new to Scotland after 2000. The English names below are those currently used by the British Dragonfly Society. In a recent account of the dragonflies of Ireland, the opportunity was taken to assign Gaelic names. These are shown below where a species occurs in both countries. They were designed to more accurately reflect features or characteristics of each species – for example the Beautiful demoiselle’s Irish name means ‘Jewel-wing’.
|English name||Scientific (Latin) name||Latin translation||Ainm Gàidhlig|
|Damselflies||Zygoptera||Paired wings||Cuileagan Cruinneig|
|Beautiful Demoiselle||Calopteryx virgo||Beautiful winged virgin||Òigheag Bhrèagha|
|Banded Demoiselle||Calopteryx splendens||Shining beautiful wing||Òigheag Ghleansach|
|Emerald Damselfly||Lestes sponsa||Robber bride||Cruinneag Uaine|
|Large Red Damselfly||Pyrrhosoma nymphula||Red-bodied small bride||Cruinneag Dhearg|
|Northern Damselfly||Coenagrion hastulatum||Widespread (thing) living in the fields marked with a little spear.||Cruinneag a’ Chinn a Tuath|
|Azure Damselfly||Coenagrion puella||Widespread (thing) living in the fields, young woman.||Cruinneag Liath|
|Variable Damselfly||Coenagrion pulchellum||Widespread (thing) living in the fields, pretty.||Cruinneag Chaochlaideach|
|Common Blue Damselfly||Enallagma cyathigerum||Probability of confusion carrying a goblet-shaped mark||Cruinneag Chumanta|
|Blue-tailed Damselfly||Ischnura elegans||Thin tailed, elegant.||Cruinneag Ghrinn|
|Dragonflies||Anisoptera||Unequal wings||Tarbh Nathrach|
|Azure Hawker||Aeshna caerulea||(Aeshna has an uncertain meaning), sky blue.||Tarbh Nathrach Liath|
|Common Hawker||Aeshna juncea||Of the rushes||Tarbh Nathrach nan Cuilcean|
|Migrant Hawker||Aeshna mixta||Multi-coloured (spots)||Tarbh Nathrach Ballach|
|Southern Hawker||Aeshna cyanea||Brilliant Blue||Tarbh Nathrach a’ Chinn a Deas|
|Brown Hawker||Aeshna grandis||Large||Tarbh Nathrach Ruadh|
|Emperor Dragonfly||Anax imperator||Master emperor||Tarbh Nathrach Ìmpireil|
|Vagrant Emperor||Hemianax ephippiger||Half-master with saddle markings||Tarbh Nathrach Dìollaideach|
|Hairy Dragonfly||Brachytron pratense||Short abdomen of the meadows||Tarbh Nathrach Gaoisideach|
|Golden-ringed Dragonfly||Cordulegaster boltonii||Club-shaped abdomen named after Bolton||Tarbh Nathrach Òrfhàinneach|
|Downy Emerald||Cordulia aenea||Club-shaped abdomen with a metallic sheen||Smàrag Umha-dhathte|
|Brilliant Emerald||Somatochlora metallica||Green body with a metallic sheen||Smàrag Ghleansach|
|Northern Emerald||Somatochlora arctica||Green bodied of the Arctic||Smàrag na Mòintich|
|Four-spotted Chaser||Libellula quadrimaculata||Spirit level (this was T-shaped like the dragonfly) with four spots||Ruagaire Ceithir-bhallach|
|Broad-bodied Chaser||Libellula depressa||Spirit level with the flattened abdomen||Ruagaire Leathann|
|Keeled Skimmer||Orthetrum coerulescens||Straight abdomen that becomes dark blue||Uachdarair Dìreach|
|Common/ Highland Darter||Sympetrum striolatum||Narrow abdomen with three stripes on its body||Gathair Cumanta|
|Red-veined Darter||Sympetrum fonscolombii||Narrow abdomen names after Fonscolombe||Gathair Dearg-fhèitheach|
|Yellow-winged Darter||Sympetrum flaveolum||Narrow abdomen with yellow (wings)||Gathair Buidhe-sgiathach|
|Ruddy Darter||Sympetrum sanguineum||Narrow abdomen with blood red (body)||Gathair Dearg|
|Black Darter||Sympetrum danae||Narrow abdomen with a golden body||Gathair Dubh|
|White-faced Darter||Leucorrhinia dubia||Doubtful (initially there was doubt over this species identity) white nose||Gathair Bàn-aghaidheach|
* includes ‘Highland Darter’ (see section on “Moorland mires and flushes”)
First encounters – the widespread species
Scotland is on the edge of the British range of many Odonata, and relatively few dragonflies or damselflies are widespread throughout Scotland, even at low altitudes. This is especially so north of the Highland Boundary Fault.
Perhaps surprisingly, it is amongst the smaller, weaker-flying damselflies that several really well-distributed species are to be found. Three can occur literally almost anywhere, provided the water is not too polluted or deep. The Large red damselfly Pyrrhosoma nymphula and Common blue-tailed damselfly Ischnura elegans will both readily colonise garden ponds, and use weedy ditches, and other very small water-bodies, as well as using more acid sites, such as bogs, at moderate altitudes. The attractive metallic-green Emerald damselfly Lestes sponsa occurs wherever there are pools with rushy or well-vegetated margins in the lowlands (as well as on moors). It may even use seasonal pools – for example on sand dunes. Its habit of resting with its clear wings half-open, instead of folded over the body like other damselflies, is distinctive.
The Azure damselfly Coenagrion puella is another widespread blue-bodied species of similar habitat range throughout the most of the UK, but it is not found in far into the Highland region. It can be abundant at small pools with rank emergent vegetation.
The extremely common Common blue damselfly Enallagma cyathigerum is perhaps the hardiest of all the damselflies and is often the only species of Odonata to be found in bare-margined hill lochs, occurring at altitudes of up to about 350m. Unlike the others previously mentioned, it seems to need areas of deeper water fairly free of vegetation and likes to fly well out from the banks. Males often occur in large numbers and will settle in close proximity in favoured spots on emergent stems, awaiting females to re-appear after egg-laying under water. It is the only Odonata species regularly found in Shetland.
Of the true dragonflies, the ‘moorland species’ Common hawker Aeshna juncea, Four-spotted chaser Libellula quadrimaculata and Common and Black darters Sympetrum striolatum and S. danae will be found in many habitats throughout Scotland, except in the most northern or exposed areas, but tend to prefer rather acidic sites. Some are more tolerant than others: the Four-spotted chaser likes pools with extensive vegetated shallows whereas the Common darter will accept even a bare-margined reservoir. All will use large garden ponds, especially if these are not far from more ‘typical’ habitats.
Important habitats for dragonflies and damselflies in Scotland
The wide range of environmental conditions throughout Scotland has resulted in a landscape where wetlands occur at all altitudes and latitudes. These vary enormously from fast-flowing streams on steep hillsides, to bogs in moorland and woodland, as well as meandering streams, lochans and ponds, both artificial and natural. From pools at altitudes of up to 600m to brackish rock pools at sea level – and all the wetlands in between – there is an almost endless variety of habitats to support Scotland’s unique dragonfly and damselfly fauna.
Temperature plays an important part in the distribution of these insects. The Gulf Stream warms sheltered parts of the west coast and Morayshire, enabling species to occur there that would not survive harsher weather conditions. At the other extreme, the cool, drier ‘continental’ climatic conditions of the glens of Deeside and Speyside are preferred by our rarest damselfly, the Northern damselfly Coenagrion hastulatum.
Acidic bogs in moorland are favoured by several species, and one of our special hawker dragonflies breeds only in such habitats. Others variously use peaty lochans, or shallow acid bogs or deep bog pools in woodland. Runnels leading from or into bog systems are often less acidic, and support one of Scotland’s scarcest dragonflies. Sheltered, rich, lowland lochs with tall-emergent vegetation attract yet another of our ‘specialist’ Hawker species, and a few gentle streams in broad river valleys of the south and west have populations of the only truly river-dwelling Odonata in Scotland – the demoiselle damselflies.
It is worth noting that the habitat requirements for a particular species in Scotland may not always be the same as in England, or elsewhere in Europe. Such differences may perhaps reflect adaptation to ‘edge of range’ situations. Equally however, some species may occupy a similar unique habitat type wherever they occur. In all the situations where the rarer Scottish species breed, populations of our more widespread, less specialised, species will also be found.
Forest bogs and lochans
Levels and depressions in acid, wooded ground from Spinningdale on the Dornoch Firth in north-east Scotland and throughout the country to Argyllshire and the south-west tend to have bogs dominated by the acid-loving Sphagnum mosses.
In the finest of these areas the bogs are amongst ancient woodland – predominantly of Scots Pine and Birch. This is especially so in some of the magnificent valleys running west of the Great Glen – such as Glen Affric and Glen Strathfarrar. Similar habitats occur between the Beinn Eighe massif and Loch Maree in Wester Ross, as well as in Speyside in the east and to a lesser extent in Perthshire and Stirlingshire, and right down through Argyll.
The Northern emerald Somatochlora arctica lives in such areas and, apart from a tiny colony in Ireland, the Scottish populations are unique in the British Isles. Although it has a wide distribution there, it is difficult to find. The shallow bogs and runnels it breeds in can be very small. On emergence, the flying insect immediately heads for the treetops and does not return to a bog until seeking a mate. Males usually fly only in bright sunshine in the warmer part of the day. Despite emerald-green eyes, the female can be difficult to spot as she flies from place to place, distributing her eggs over a wide area and she may disappear from a site for an hour or more at a time.
In lochans in some wooded glens one or both of the two other Emerald dragonflies occur. Both Downy emerald Cordulia aenea and the Brilliant emerald Somatochlora metallica have very disjunct British distributions, and the Scottish populations are of special ecological interest. Of the two, the Brilliant tends to be in lochans at slightly higher altitude, and in Argyllshire even in treeless, exposed sites, whereas the Downy emerald is found in wooded sheltered situations. Both species are fast-flying – the blackish colouration of the Downy, and rather ‘club-tailed’ appearance of the male, help to identify it.
Small deep Sphagnum-rich pools in woodland bogs, support the White-faced darter Leucorrhinia dubia. An attractive, rather weak-flying species, its exacting habitat-requirements make Scotland the main centre of its British distribution. It occurs from Applecross in the west to Grantown-on-Spey in the east, in the glens of western Scotland and as far south as Perthshire and Rannoch Moor.
In Speyside, Aberdeenshire and Perthshire the sheltered, still waters of lochans that have dense emergent vegetation of sedges are home to Scotland’s rarest and most endangered Odonata species, the Northern damselfly Coenagrion hastulatum. It occurs nowhere else in the British Isles, and seems dependent on the particular micro-climate of these areas. All of its few known long-established sites are lochans where a constant water depth of 30cm or more is maintained by a dam, with continuous inflow from higher ground.
Moorland mires and flushes
The Odonata interest of moorlands is mainly in the grass, sedge and bog moss dominated landscapes, rather than the iconic, managed heather-clad hills, which are often too steep and too dry.
Flushes in moorland may show subtle differences in their acidity and other characteristics. In the west of Scotland one tiny acidic patch of bog, the only area around with obvious Sphagnum, sufficed for the emergence of a small number of the Northern emerald; close by, a narrow seepage channel about 15cm deep had larvae of the Keeled skimmer Orthetrum coerulescens. The latter is very scarce and mainly confined to milder climates of the west. It seems to need the influence of slightly mineralised water, and sometimes uses runnels or deltas formed when run-off from a hillside fans out on reaching flatter ground.
The Golden-ringed dragonfly Cordulegaster boltonii also patrols such runnels and seepages. It breeds in running water, and in Scotland may use anything from roadside ditches to quiet streams several metres wide, if flow-rate and stream-bed conditions are suitable. It is widespread in the Highlands, though much scarcer in eastern Scotland.
Highly acidic bog-pool complexes in open exposed situations, sometimes forming ‘patterned mires’, are another distinctive element of moorlands. This habitat supports the Azure hawker Aeshna caerulea, which is found nowhere else in the British Isles. It occurs from sea level to altitudes of 500m or more. Breeding sites are often tiny, shallow bog-pools. Ideal pools may be only about. 20cm deep, over a thick, soupy substrate of peaty detritus. Deeper water is preferred by the Common hawker Aeshna juncea, which may share the same habitat. Small bog-pools get noticeably warm on a dry hot summer’s day and are very susceptible to drying out. This potentially disastrous effect has been observed in recent years in many parts of the Azure hawker’s range. Its populations stretch from Forsinard in the Sutherland ‘Flows’, down to Perthshire and Rannoch Moor, with an outpost in Galloway. For the reasons given above, no one bog pool could be considered as a ‘site’ for this species: a whole complex of such pools is required to sustain a population.
The Black darter Sympetrum danae also breeds in such situations, as well as in a variety of acidic woodland, moorland flushes and peaty lochans, and is well distributed throughout Scotland. A summer-emerging dragonfly, it may attain large numbers at favourable sites.
On lower ground on the western fringes, from Cape Wrath to the Hebridean islands and Kintyre, the so-called Highland darter Sympetrum nigrescens has long been known. The males are red-bodied as in the Common darter. It may simply be a heavily marked form of that species but has been claimed to be specifically distinct. More ‘typical’ Common darters have only recently spread north throughout much of Scotland and may now occur in many of the same areas. Until further scientific study resolves the matter, both ‘species’ in Scotland are best referred to as Common darters.
Rivers and streams of the south and west: domain of the Demoiselles
Even in the warmer conditions of southern Britain, rivers support only a few dragonfly and damselfly species. In Scotland, river head-waters are often in the hills, where they are regularly fed by relatively high rainfall, and often snow melt-water in winter. The resulting powerful flow and relatively low water temperatures for a large part of the year, tend to make most of these water-courses unsuitable for warmth-loving Odonata. Nonetheless, a few rivers and streams in sheltered low-lying areas of southern and western Scotland hold the spectacular demoiselle damselflies, at their most northerly sites in Britain.
Shallow, gravelly streams in the wooded lowlands of Argyll and Inverness (including the islands of Isla, Jura and Mull), are home to scattered colonies of the Beautiful demoiselle damselfly Calopteryx virgo. The jewel-like, violet-iridescent wings and body of the male give it the appearance of being an exotic, tropical insect. Males need overhanging vegetation on which to perch to look out for passing females. When one appears, they fly out and use rapid movement of their broad, butterfly-like wings in a courtship flight, enticing the female to mate near a suitable egg-laying site. Such activity is fascinating to watch and the demoiselles are two of the only three British Odonata to exhibit true courtship behaviour.
The closely related Banded demoiselle Calopteryx splendens behaves in much the same way, though it prefers sluggish silty rivers in less shaded situations. Its breeding presence in Scotland was only discovered in 2004, until when the limits of its UK range were thought to be on the south side of the Solway, and in Northumbria. It now seems that it is well-established on one small, south-flowing, coastal river in Kirkcudbrightshire, though how long it has been there is not known. This warm, sheltered area has few similar rivers, so whether the species could ever extend far into Scotland is debatable.
Slow-flowing backwaters of rivers and streams may sometimes be used by species normally found only in still waters; the Golden-ringed dragonfly discussed earlier prefers boggy moorland streams and runnels, but does sometimes use edges of larger watercourses.
Richer lowland lochs
The mild, coastal lowlands of Galloway and Argyll are home to ‘outpost’ populations of dragonflies and damselflies which are scarce or of limited occurrence much further south in northern England.
Sheltered, shallow lochs, which are not too acid and are fringed with fens of Common reed Phragmites australis or Common club-rush Schoenoplectus lacustris (also, rarely, Great fen-sedge Cladium mariscus), support the Hairy dragonfly Brachytron pratense. Its name refers to the especially hairy thorax, believed to help conserve heat in the cool, early-emergence season. The species appears during May and is rarely seen after early July. Its distinctive larvae like to cling to the underside of litter of the tall-emergent plants, and will often ‘play dead’ if disturbed or handled.
The same habitats contain important colonies of the Variable damselfly Coenagrion pulchellum, a species which is rare and vulnerable in the UK north of Wales. Its similarity to the more widespread Azure damselfly often leads to confusion over identifications, and an expert opinion is needed to confirm its presence at unrecorded sites. The “Variable” lives up to its name and the markings on both thorax and abdomen can sometimes be difficult to interpret. The situation is not helped when both species occur at the same site!
Both Hairy dragonfly and Variable damselfly species extend as far north as the Black Lochs, near Oban. Because of the range of habitat conditions here (from neutral to acid in character), this area has the highest number of Odonata species recorded for anywhere in Scotland – 14. The Hairy dragonfly has recently been found at other sites near the Argyll coast where the aspect is sheltered and east-facing.
Another species of less acid waters, the Southern hawker Aeshna cyanea, has a scattered occurrence at these westerly sites and northwards to the lowlands around Inverness. Elsewhere in Britain and Ireland it is a frequenter of woodland pools, and the most familiar dragonfly of garden ponds. The species is now seen with increasing frequency in the south of Scotland. A recent discovery of larvae in tiny, brackish, rock-pools not far above the tide line on the east coast of Mull, shows the adaptability of this species at the edge of its range!
Vagrants, migrants and colonists
Like Painted lady butterflies and other insects, some species of dragonfly show strong tendencies to undergo long distance ‘migrations’ or large scale dispersals at irregular intervals when conditions are favourable and numbers high. By this means new areas may be colonised, sometimes only temporarily if conditions where they arrive are marginal for their survival.
Movements into the British Isles from Europe often include widespread species such as the Four-spotted chaser and the Common darter, but more excitingly for dragonfly enthusiasts, they can also include southerly species which have no permanent base here. The weaker damselflies are less often involved, but several species have been extending their permanent ranges quite rapidly in recent years, resulting in ‘new’ species entering the UK.
Being closest to the continent, the south and east of England are the most exposed to these influences and only a few stragglers from larger influxes seem ever to have reached Scotland. Red-veined and Yellow-winged darters Sympetrum fonscolombii and S. flaveolum for example have both been noted in Scotland on only a couple of occasions in the past hundred years. This is also true of the Vagrant emperor Hemianax ephippiger– a more solitary wanderer from warmer climates, which has the distinction of being the only dragonfly to be recorded in Iceland.
Though a common resident in southern Britain, the Brown hawker Aeshna grandis is as rare in Scotland as these continental species. An occurrence in the Hebrides in 2004 could perhaps have derived from Ireland, where it also breeds.
Several species have been extending their UK breeding ranges for many years. In the vanguard of these, the Common darter (as distinct from its resident ‘Highland’ form) has spread widely in Scotland after being scarce until the 1970s.
Since 2000, four species have reached Scotland for the first time. The Emperor dragonfly Anax imperator, Broad-bodied chaser Libellula depressa and Ruddy darter Sympetrum sanguineum were all seen in 2003 and Migrant hawker Aeshna mixta the following year. All these species are essentially lowland insects that will tolerate a wide range of habitats, and have the ability to act as ‘pioneers’ at relatively newly created sites. They will often turn up and breed for a few years and then re-appear elsewhere. They should be looked for especially near coasts, and most of all in the south and south-east of the country.
The biggest threat to dragonflies and damselflies probably comes from loss of habitat, changes in land management and urban/industrial development.
Pollution is a major cause of concern, especially sewerage, industrial effluents, diesel, excess sediments, run-off from fertilisers used in agriculture, wind drift from insecticides, and the consequences of using herbicides on marginal vegetation. Pollution may be particularly devastating in streams, rivers and pools or lochs with inflows.
Aquatic habitats used by odonates (damselflies and dragonflies) may be lost through drainage or over-abstraction of a watercourse. Serious impacts on flowing water species can also occur following the canalisation of rivers or as a consequence of certain flood prevention schemes.
Species with a northerly distribution, such as the Azure hawker, the Northern emerald and the White-faced darter mentioned earlier, may be severely affected if temperatures rise as a result of climate change. The drying out of small bog pools, as a result of either drainage or climate change, or a combination of both, could be particularly disastrous for the Azure hawker with a larval life that can extend for up to four years
Changes in land management may take several forms, and one of the most harmful to Odonata habitat in Scotland, side by side with destructive peat cuttings on an industrial scale, may well be afforestation. The Northern damselfly, for instance, has been lost from one of its long-established site due to the combined effects of afforestation and drainage. Conservation work in Speyside, blocking drains to improve the habitat for birds has, unintentionally, created suitable temporary habitats for this damselfly species, but these provisional havens may become unsuitable if the water levels cannot be maintained.
Inappropriate habitat management can have catastrophic impacts. Drastic modifications to water bodies or their surrounding vegetation can eradicate populations. At the other end of the scale, a complete lack of management can result in the water being shaded out by surrounding trees and shrubs or choked with silt and plants accumulated over the years.
Overstocking ponds with fish has immediate negative impacts as they are natural predators of dragonfly larvae. In addition, bottom-feeders such as carp disturb sediments, which can muddy waters to such an extent that submerged plants cannot grow any longer and in turn make the site unsuitable for dragonflies.
Widlfowl can cause physical damage to the banks through much trampling and grazing of the marginal vegetation and are a source of chemical pollution due to nutrient enrichment from their droppings. Disproportionate nutrient input can, for instance, cause algal blooms and excessive growth of duckweed, which in turn prevent any light getting into the water, any plant growth and any aquatic insect life.
Excessive wave action from boat drift and other unnatural fluctuations in water levels can have severe impacts on odonate populations as well, either through direct impact at the peak of dragonfly emergence, or indirectly through damage to marginal vegetation and erosion.
Red List and Biodiversity Action Plan (BAP)
The Red Data List for Insects include two species found in Scotland: the Northern damselfly Coenagrion hastulatum is classed as Vulnerable, and the Northern emerald dragonfly Somatochlora arctica is classed as Rare.
There is currently only one odonate on the list of Priority Species in the Scottish Biodiversity Action Plan: the Northern damselfly Coenagrion hastulatum
(see www.biodiversityscotland.gov.uk for more information).
Conservation –how you can help dragonflies and damselflies
The British Dragonfly Society (BDS) and its Dragonfly Recording Network (DRN) always need new records in order to re-assess the status of dragonflies and damselflies in the UK regularly. All records of sightings are welcome and anybody can participate in dragonfly monitoring
Practical steps – Creating and managing habitats
The key to the conservation of dragonflies and damselflies is the quality of the water as a habitat for larvae (given that most species are sensitive to pollution and can be used as indicators of the health of the site in which they occur,) and the availability of a mosaic of terrestrial habitats for the adults. An ideal situation consists of a mixture of both long and short grassland and even bare ground near the water’s edge, with scrub and woodland nearby. This should provide areas for hunting, roosting and basking away from the intense competition that can exist at the breeding site itself.
“Dig a pond for dragonflies!” The creation of garden ponds for wildlife can benefit the more common and widespread species of dragonflies and damselflies. The pond should be in a sunny, sheltered location and ideally filled with rain water. Plants and animals on which dragonflies depend for shelter and food should colonise naturally, over time. If instant results are preferred, the alternative is to plant selected marginal vegetation around the edges, and floating-leaved plants and oxygenators in the water, making sure that only native plants from a reliable source are used.
When contemplating pond creation, consider suitable sites, preferably within 200m of an existing pond. Existing ponds should be retained and, where possible, scrub prevented from obscuring the sunlight and pond margins protected from poaching by livestock. If it becomes necessary to clear out bank-side vegetation and remove silt, this should only be carried out in the autumn, and at least one third of the pond area should be left undisturbed in any one year.
It is generally advised not to cultivate soil or apply fertilisers and insecticides close to rivers and streams. A careful individual assessment is necessary but as a guide a 10m buffer zone is the minimum suggested in areas adjacent to any significant watercourse. Where necessary, the bank sides should be cut or mown on a rotational basis, so that some sections are left undisturbed in any year. Ideally, ditches should not be cleared more frequently than every other year between August and January (inclusive) and only one side of the ditch should be cleared at a time. A 1m grass strip should also be left between the bank top and the crop and measures should be taken to protect the banks and edges from poaching by livestock.
Managers of semi-natural habitats
The natural development of peatland bogs can lead to the disappearance of bog pools. In areas where there are few bog pools, it may sometimes be necessary to create new ones for dragonflies to colonise. In areas where encroachment by birch, pine and other trees or scrub is a problem, it may be advisable to pull out invasive seedlings, or fell and cart larger trees in order to keep the pool margins clear. However, before such management is undertaken, a careful ecological assessment should be carried out so as to avoid any detrimental impacts on other aquatic or terrestrial invertebrate species.
Finding out more about dragonflies
The British Dragonfly Society (BDS)
The BDS aims to promote and encourage the study and conservation of dragonflies and their natural habitats, especially in the United Kingdom.
(Contact details for local representatives of the Dragonfly Recording Network (DRN) can also be found on the same website)
The Dragonfly Project is a separate charity running dragonfly safaris and education courses. It currently operates from Wicken Fen, Cambridgeshire, from May to September.
The Field Studies Council runs courses on dragonflies and damselflies.
Smallshire, D. & Swash, A. 2004. Britain’s Dragonflies. WildGuides. (Features multi-photo montages of all UK species as well as keys to females and larval stages)
Brooks, S. & Lewington, R. 2004. Field Guide to the Dragonflies and Damselflies of Great Britain and Ireland. 4th edition, British Wildlife Publishing. (Contains clear and detailed drawings of all adults as well as a key to larval stages)
Powell, D. 1999. A Guide to the Dragonflies of Great Britain. Arlequin Press. (Gives beautiful artist’s impressions of dragonflies and damselflies in their natural postures).
Dragonfly Biology and Ecology
Corbet, P.S. 1999. Dragonflies – Behaviour and Ecology of Odonata. Harley Books. (The ultimate book for those serious about dragonflies)
Merritt, R. & Vick, G. S. 1983. Is Sympetrum nigrescens Lucas a good species? Journal of the British Dragonfly Society: 1: 7-8.
Habitat creation and management for dragonflies
BDS. 1993. Managing Habitats for Dragonflies. British Dragonfly Society. (This booklet can be ordered via the BDS website)
BDS. 1993. Dig a Pond for Dragonflies. British Dragonfly Society. (Orders via the BDS website)
M. Jill Lucas. . Spinning Jenny & Devil’s Darning Needle. M. J. Lucas.
Distribution maps and Atlases
Merrit, R., Moore, N.W. & Eversham, B.C. 1996. Atlas of the dragonflies of Britain and Ireland. The Stationery Office. (This was the last UK Atlas; now out of print but available in libraries)
Nelson, B. & Thompson, R. (2004) The Natural History of Ireland’s Dragonflies. Belfast: Ulster Museum.
There are many regional or county atlases (details available from the BDS website)
Sanasan Gàidhlig – Gaidhlig Glossary
|Chinn a Deas||From the south|
|Chinn a Tuath||From the north|
|Liath||Grey or light blue|
|Tarbh Nathrach||Dragonfly (literally adder-bull)|
The “h” in Gaelic.
There are no words beginning with h in the Gaidhlig language, so why does it appear in certain words? The letter h is used, following certain grammatical rules, to indicate a softening or weakening of the consonant preceding it. This is called lenition. Lenition can either change sounds e.g. mh to a “v” sound, c to the ch in loch or in some cases silence the consonant completely. The h “appeared” in the 6th century, when the Roman alphabet was first adapted for writing in Gaelic/ Gaidhlig.