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.