FIELD NOTES
APRIL 2002 continued....
ARTICLES
The Large Red Damselfly
- a Herald of Spring
For many , the sound of the Cuckoo or the sight of the first Orange Tip butterfly means that Spring has arrived; for me, it is the first time I see a Large Red Damselfly. It is normally the first dragonfly reported in spring, sometimes as early as mid April. 'Large' Red is something of a misnomer because , although robust when compared with the incredibly fragile Small Red (not found in Hertfordshire) , it is a delicate needle-like insect. Its abdomen is no more than 25-29mm and hindwing only 19-24mm long.
Although small it is not insignificant . Its distinctive bright red and black markings, which are unlike any other dragonfly seen in Hertfordshire, make it easy to identify. Its name, however, like those of so many of the British Dragonflies, is prosaic and unimaginative. In Latin it is Pyrrhosoma nymphula, 'the Flame-bodied water nymph', a name that captures the spirit of this fiery flying jewel.
Damsels in your garden - The Large Red is common and widespread throughout Britain and continental Europe. It occurs in a wide range of habitats, including acid bogs, quieter stretches of fast streams and rivers, well vegetated ponds, canals and ditches. In Britain it is less common in chalky districts, like north Herts around Royston, and has declined in areas of intensive cultivation. It is often seen at garden ponds in most parts of the County, with recent records from Cheshunt, St Albans, Borehamwood, Bushey, Harpenden, Hertford and Hitchin. The considerable increase in numbers of garden ponds, partly due to the availability of fibreglass and PVC liners, has made them an important habitat for this and several other dragonfly species.
Unpolluted ponds with good marginal, emergent and floating vegetation in sunny but sheltered positions (and preferably without fish) are suitable for dragonflies. If you have a pond , take a look at it in early to mid May when the small, dark larvae of the Large Red are preparing to emerge. They live among waterweeds and bottom debris and usually take 2 years to develop.
In their second spring, most respond en masse to rising temperatures and increased day length, so that adult emergence occurs over a short period of about 3 weeks. This is a survival strategy to ensure that the maximum number mature at the same time, which enables them to find mates more easily. Continued bad weather during emergence and flight periods can endanger success. A smaller unsynchronised emergence later in the summer helps to counteract this risk and a few are still on the wing until September.
The larvae are normally well hidden among waterweeds, but prior to emergence will become more visible near pond edges or can be seen basking in warm shallows. Emergence often occurs early in the morning, when larvae climb the stems of emergent plants and begin the transformation from a drab water dweller to a bright ethereal flyer. The larval skin splits and the adult insect heaves itself free, leaving the fragile husk of its former self clinging to the plant.
The newly emerged (teneral) insect is pale in colour (it may take several days to reach full adult colouration) with small crumpled wings. Its nondescript hue helps to hide it from predators until it has pumped fluid into its wings; but it cannot fly and is very vulnerable to predators, such as birds, spiders, ants and to bad weather; mortality at this stage is high.
The discarded larval shell (exuvia) can be identified down to species level and is important evidence of breeding. Collecting exuviae is an important part of the survey work for the Herts Dragonfly Group's Atlas project and I would be pleased to receive exuviae from HNHS members for identification. ( Old photographic film containers are suitable for ensuring they survive postage.)
The process of emergence is fascinating to watch and easy to photograph. When the teneral damselfly takes its maiden flight it goes away from water and, while immature, can be found feeding among garden borders, in sunny patches in woodlands or along hedge margins, sometimes in large numbers. Typical prey will be small moths, Alder flies and Mayflies.
Adults take 6-15 days to mature, after which the mature adults return to water to reproduce. Males often perch on waterside vegetation or fly out to investigate potential competitors or mates. Mature adults live on average about a week, although some may survive 35-45 days.
Prior to mating , males transfer sperm from primary genitalia at the end of the abdomen to secondary genitalia on the underside of the abdomen just behind the thorax. When they find a female , they normally take her in flight by clasping her behind the head and after a short flight in tandem perch together, while the female bends her abdomen round to join with the secondary genitalia of the male for sperm transference to occur.
Mating takes about 15 minutes and females insert eggs into tissues of submerged plants or underneath floating leaves with the male in tandem. Mating and egg laying is frequently observed at garden ponds.
Records please! - As well as exuviae , I would also like HNHS members to send me records of adults of Large Red and other species observed at garden ponds (and elsewhere) to add to the distribution data for the Atlas. The minimum information needed is your name, date and location of the observation (preferably with a six figure grid reference). Numbers seen and any breeding behaviour observed is also very useful. Please send exuviae and records to Christine Shepperson, 63 Station Road, Smallford, St Albans, AL4 0HB, Email: shepperson@herts.ac.uk.
Places to look - If you do not have a pond or would like to look for Large Reds in the wider countryside , I list a selection of sites where the Large Red Damselfly has been seen over recent years .
| Site | Grid |
| |
| Astonbury Wood Ponds | TL275213 |
| Ayot Green Village Pond | TL220139 |
| Bencroft Wood Pond | TL329064 |
| Berrygrove Wood | TQ133981 |
| Brickendon Village Pond | TL323079 |
| Bricket Wood Common | TL132008 |
| Highfield Wood Pond | TL348084 |
| Hoddesdon Park Wood | TL355085 |
| Chipperfield Common | TL048013 |
| Chorley Wood Common | TQ033965 |
| Park Street Gravel Pits | TL150032 |
| Hadham Mill Pond | TL429176 |
| Hertford Heath NR | TL350105 |
| Silvermeade NR , Broxbourne | TL372063 |
| Lemsford Springs | TL223122 |
| Patmore Heath NR | TL443257 |
| Potten End Village Pond | TL017088 |
| River Colne , Colney Heath | TL201059 |
| River Gade , Water End | TL033107 |
| River Lea , Stanborough | TL230105 |
These attractive and fascinating damselflies will be emerging very soon; I hope you will go out in search of the 'the Flame-bodied water nymph'and look forward to receiving records and exuviae.
Christine Shepperson
Joint County Dragonfly recorder
Page Seven
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