Small Red-eyed Damselfly

John Solomon, 24th July

          The UK’s three commonest Damselflies are the Common Blue, the Blue-tailed and the Azure, and they can be found throughout our islands, even up into Scotland. In the lower half of England, not so much into Wales, broadly below a line drawn across between Liverpool and Kingston-upon-Hull, they are joined by a fourth, the Red-eyed Damselfly. This last is not as ubiquitous as the other three and, although it tolerates different acidity fairly well, prefers still water. It likes larger ponds, lakes, canals and very slow flowing rivers. It demands emergent and floating vegetation, such as lily pads and pond weeds, and loves to flit around away from the bank and over the water. The insect is fairly easy to identify, even though it may be several yards away, as the dark, red eyes and black back of the thorax make it look almost as if it is wearing a dark cloak.

          In the 1990s a very similar species was expanding its range in Germany and the Netherlands and, in July 1999, it was discovered over here, at three sites in Kent. The Small Red-eyed Damselfly had landed. It established itself in its new home with extraordinary rapidity and by just 2002 it had become locally abundant in south-east England. Now it has become widely spread in a triangle roughly described by a diagonal line heading up, north-west, from Brighton to Northampton, then across to The Wash. It is establishing colonies throughout a larger area described by a line drawn upwards diagonally north-east from Exeter to Kingston-upon-Hull. Unhelpfully, this is a very similar area to that in which the Red-eyed may be found. It also likes the same environment as its larger cousin, and has the same behavioural characteristics, enjoying dancing out across the open water and landing on emergent and floating vegetation away from the bank … and you!

          This behaviour and its strong similarity to the commoner Red-eyed Damselfly make it difficult to identify, and for a number of years, watching the spread of the insect across the country, nature-watchers in Andover had wondered if it had managed to reach and establish itself here.

          In 2017 I was very new to the world of odonata and was simply going out there and hunting any insect I could with my trusty bridge camera and snapping away. Later I would get back and pop the results up on the computer screen to see if I had anything, and, if so, then open the book and try and find out what. During the autumn I heard that a local Otter expert had found Small Red-eyed on both Rooksbury and Charlton lakes and had the photos to prove it. Unfortunately, in spite of requests, neither I nor anyone else has managed to actually see the photos he had, but a fire had been lit. It was the time of year for ploughing through all those I’d taken, reviewing them and editing what I would keep and what I would trash, and I had found Damselflies on both lakes that had red eyes. I set about analysing what I had, always with the foolish optimism that would be the lucky little bear that had accidentally snapped the rarity.

          Astonishingly, I found that I had caught a mating pair at Charlton Lake:

          Having discovered their presence there, come the next year, the hunt was on. Unfortunately, fate was not with me. In 2017 there had been plenty of emergent and floating vegetation right up to the bank near the car park of the lake. In 2018 that had all gone and the nearest such vegetation was yards away and well out reach of any camera I had. Anton Lake looked extremely good as a potential site, having large areas of floating and emergent vegetation, but there, too, it was at least 6-10 yards away from the bank. As I suggested to the area Dragonfly recorder, only half in jest, we need a boat. Forget a bigger one, we just need a boat!

          The boat was not forthcoming … but rain was.

          The water level of Andover’s lakes began to rise quite quickly and, although I have understanding of why, this seemed to encourage the spread of emergent vegetation and the growth of an aquatic moss that seems to affect all three of Andover’s lakes. By last year this became obvious, but it still wasn’t close enough, then, this year it looked as if it was.

          On Monday 19 July I visited Charlton Lake and sat down for a while on the edge of the bank, by the car park, to see if there were Damselflies of any type with red eyes … and there were. I fetched the camera from the car and started taking photos. The insects weren’t as close as I would have liked, but modern technology is a wonderful thing … when it works. One of its great gifts is being able to take a photograph and then, immediately, not just see if it has come out okay but also zoom right in and examine what’s there. This might seem a big “so what?” to many of you reading this but I first picked up a camera when people still remembered pinhole cameras. I grew up with rolls of film that you didn’t get developed until you’d shot the whole roll. Then you had a wait of a week until the results came back … and you couldn’t touch them up or improve them on a computer. Those were the days! Thank God we’ve moved on!

          One of the first shots I took turned up trumps:

          Yes, it’s not a great shot, it’s not very sharp and it’s not beautifully posed and composed … I know these things! It was a good two yards away and it’s been cropped to death, but what mattered was that I could see enough to positively identify it as a male Small Red-eyed. I took a stroll around that end of the lake, to try and find more and get some idea the size of the colony there, but that was the only part of the lake where the vegetation on and in the water came close enough to the bank. Incidentally, there was a lot of Emperor Dragonfly action on the lake, and I saw three females busily engaged in egg-laying, which was  excellent.

          My next trick was to visit Anton Lake, which I did the next day, in spite of not having any time to spare. The most suitable part of the lake for species I considered to be the east end, nearest Andover town, and I went and sat on a fishing pier overlooking it. I had barely touched down when a Damselfly with red eyes landed and couple of yards away on the floating moss that covered so much of this art of the lake. I snapped and caught:

          They were here! I didn’t have the time to spare to investigate properly, so I left with a plan. I was due to walk the Anton Lake transect later in the week. I would have more time and I would take a good look around. On the Thursday, that is precisely what I did. It was another very hot day and I sat on the same fishing pier, snapped, examined the photo and snapped again. Most of the insects were not coming close enough, but of those that were I managed to positively identify all 14 as Small Red-eyed Damselflies. Very encouragingly nearly all were locked in tandem as egg-laying pairs … mind you, perhaps that explains why they have spread across the country so quickly!

          Moving on around that end of the lake there were plenty of insects out over the water. It was impossible to identify them as going around the lake meant that they were silhouetted by the sun, but it was reasonable to assume that a good percentage were Small Red-eyed. Even more, the area of suitable vegetation at that end of the lake covered a good two acres. Judging by the numbers I’d seen in a very small patch, around 3 yards in diameter, this is clearly a sizeable colony.

          Identification of Small Red-eyed is difficult because they tend to be yards away. I recommend the use of a strong lens! A bridge camera with a super-zoom is a very suitable weapon. They are also very similar to the standard Red-eyed. I haven’t been able to get what I would call the definitive shot of either the male or the female, for the reason just mentioned, but I should be able to show you enough. I’m going to start by cropping in on the first photo I took of them, the mating pair:

          This focuses on the male attaching himself to the back of the female’s neck with his claspers.

          First we’ll take the female. If you look at the pale green shoulder stripe that runs along the side of the upper surface of the thorax you will see that it is complete and runs the whole length. This is a female standard Red-eyed and she clearly has a very indistinct and broken shoulder stripe. Very often the female has no stripe at all:

          Moving on to the male here is another I took at Anton Lakes:

1 – circles the last segment of the abdomen, section 10. Unlike the standard Red-eyed the blue colour that circles this section is broken by black. This can also just be made out in the cropped photo of the mating pair.

2 – shows a “blob” of blue colouration that reaches up from underneath the abdomen on section 8. The standard Red-eyed does have some colour reaching up but in the Small Red-eyed it is more marked.

3 – highlights a similar swell of blue colour on section 2 that runs along into section 3. The standard Red-eyed has nothing like this.

4 – focuses on the side of the upper thorax where, as with this specimen, there is a green shoulder stripe. In this case short but it can stretch along the whole length as with the female. The Standard Red-eyed male doesn’t have this

          This is a standard Red eyed male, compare and contrast:

          I have since visited Rooksbury several times, search for the insects there, but with no luck at all. On the other hand I have seen very few Damselflies with red eyes round there at all lately, so I shall persevere.

          Good hunting!

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