Despatches from Terroir North:

North Wales, in common with most of the UK, has suffered from a distinct lack of butterflies this year - not just in numbers but also in the range of species. That this is, for the most part, attributable to prolonged spells of cold and wet weather is not in doubt, and it is only in the last few weeks that the numbers appear to be rising a little.

‘Where have all the butterflies gone' scream many newspapers, clearly short of major events to record (I think they call it clickbait these days!).  Nevertheless, such headlines highlight the fragile nature of these much loved insects, and how one miserable summer can have a devastating effect on butterfly populations (and, maybe, on their long term recovery).  What these editors appear to have overlooked, however, has been an ongoing and disturbing decline in butterfly numbers over several decades.       

Diminishing butterfly populations: from left to right - common blue, small tortoiseshell and small copper (all images © Richard Stephens)

So, given the lack of butterflies here in the depths of a cold and damp north Wales, the members of Terroir North turned their attention to another spectacular group of insects – the Odonata.  Better known as dragonflies, this group includes both dragonflies and damselflies of which there are some 57 species recorded in the UK and around 5,000 species worldwide. Of that 57, a significant number are rare ‘vagrants’ and several are confined to very specific localised parts of the UK. In reality, therefore, we realised that around only 30 species were likely to be found, and eventually identified, by the intrepid Terroir team. 

Image above: male southern hawker masquerading as a full sized dragon

A bit of biology now. These flying insects are incredibly short-lived - maybe  a week or so for damselflies and two to three weeks for most dragonflies. During this time they feed mainly on other smaller insects. The larger dragonflies will happily consume butterflies, moths and even smaller dragonflies. Nothing is safe. 

Images above: immature emperor dragonfly demolishing a bee

Most of the dragonfly life cycle, however, is spent in water. The flying females normally lay eggs under the water. These slowly develop into a larva, moulting several times until eventually emerging (after from six months to six years depending on the species), as a full-grown adult.

The trouble with these insects is that, in their winged form, dragonflies tend to be extraordinarily active, flying at great speed and performing aeronautical acrobatics with ease.  The smaller damselflies are generally more sedate and are relatively easy to observe - that is until you realise that several species are extraordinarily similar! Identification revolves mainly around the abdominal segments; many species have an assortment of blue colouration, but the key is the relative position and frequency of these blue segments.

The Odonata are loosely classified into their basic flying habits (or jizz as its known). So we have the hawkers which are the larger dragonflies because they prowl around, a bit like a bird of prey. Then there are the darters which tend to dart around but then settle, which helps identification, always assuming you know where they have darted to. There are also chasers and skimmers which loosely do chase and skim - but not always!

Then there are the specific habitats preferred by the various species. Some like fresh water, some prefer still water, running water or even acidic pools and bogs. Some are upland species, most are lowland species.  Some emerge in late spring, some in late summer and most inbetween. But, because they are only around a short time, seeing them is very hit and miss, depending on when an emergence has taken place. Sometimes one species is present in vast numbers but two weeks later – they’re all gone. All in all, it’s very similar to the vagaries of looking for butterflies but with much shorter windows for some species.

Terroir in north Wales is fortunate to have a wide variety of suitable sites available to the team. The British Dragonfly Society has a very good website which lists many of the best locations in the UK, giving details of what has been seen and how to get there.  Canals and small lakes with good marginal vegetation are excellent places to visit.  Peat bogs and raised mires such as found at Fenns, Whixall and Bettisfield Mosses National Nature Reserve (on the Wales/Shropshire border),  Cors Caron (Tregaron, Ceredigion) and Cors Goch (a Wildlife Trust reserve on Anglesey) proved very productive. So too did long lengths of the little used Montgomery Canal (and its assocated overspill reservoirs) which are especially well-vegetated.

So when did we go Odonata hunting and what did we find? The key (as with butterflies) is a warm and mainly sunny day. Strong winds and lots of cloud are no good; the dragonflies just simply hunker down and are not to be seen.  Unfortunately this summer has not been blessed with many fine days but we did make sorties out to known sites where possible.

Generally we found the common blue, blue-tailed and emerald damselflies …

Hawkers seemed to be everywhere but they fly fast and furiously and rarely stop, making identification problematic. The most common seemed to be the emperor dragonfly and the southern hawker (check the colour of the thorax and abdomen), but males, females and juveniles all have different colour combinations so positve identification is really tricky.  Another relatively common dragonfly is the brown hawker which - being brown - is a fairly easy one to confirm! The common hawker and the migrant hawker look superficially identical and you need to be close up to confirm the colour details on the thorax and abdomen. Neither is rare but we found these two to be the most taxing of them all. And, of course, they are continuously on the wing which makes it even more tricky to get a close view.

Moving down in size we found a massive abundance of black darters on Cors Caron, and the common darters were overall, well, common!  Lovely surprises were a ruddy darter, black-tailed skimmers, and spotted and broad-bodied chasers on the canal and on Cors Goch. Overall, we successfully recorded over 20 Odonata species with a couple being relatively unusual for the area, including red-eyed damselflies and that ruddy darter which we pictured above. 

Would we recommend it?  Most certainly we would. It’s a fascinating group of insects and we are already looking forward to next year’s Odonata hunt - but starting a bit earlier in order to catch the spring species. 

 Ed – I hope you recorded all your sightings on iRecord? https://irecord.org.uk/