Notul. odonatol., Vol, I. No. 5, 85-96. June I. 1980 92 pp.

Proceedings of the First Meeting of British Dragonfly Recorders,

London, April 7, 1979

Compiled by D.G. Chelmick

”Bredon”, High Beech Lane. Haywards Heath, Sussex, United Kingdom

The status and distribution of the British published in 1978 and included all records

Odonata received up to May 1977. By the end of 1978

The Provisional Atlas for was so much additional information had been Notul. odonatol., Vol. I, No. 5. pp. 85-96, June I, 1980 93

Ireland and the received that it was felt necessary to update British Isles (excluding the maps. This was carried out during the Channel Islands) is 2660. Records have now

and 1979 and been 1161 of these. winter early spring of it was received from Express- these maps that formed the basis of this ing the squares recorded for each species as session. would like sincere of the total recorded I to express my a percentage squares. thanks to Bill and Bob Merritt who carried out the majority of the updating work and Table I also to David Parker from whose notes much

of this summary derives. Recorded

Cat. No. squares

The British list Current No. of published infor- of spp. as % mation on what constitutes a British species total is unclear and considerable discussion took place. It was generally agreed that all species 1 5 > 38% recorded from the British Isles should be in- 2 11 18-30%

cluded but that vagrants should be classified 3 5 8-14% as such. The Provisional Atlas for Odonata 4 6 4- 7%

(Heath. 1978) includes 44 species. Three of 5 11 <2.5% these are migrants only; Sympetrum flave- 38 lutai post 1961

olum (L). S. fonscolombei (Sel.), and S. breeding spp.

vulgatum < L.). Three further species have not

and all been seen for many years are, in pro-

extinct; of British fauna bability. they are Coenagrion ar- the status the can be categor-

C. and Table I. matum (Charp.), scitulum (Ramb.) ised as shown in Unfortunately it is

Oxygastra curtisii (Dale). Additional vagrant impractical to produce such a table for pre-

which be the 1960 data. We species, must added to list, are can, therefore, draw no con-

5 records whether the fauna as follows: species with isolated clusion as to pattern of our

from mainland Britain namely, Gomphus is changing. However, with the latest data, flavipes (Charp.). Aeshna affinis (Vander L.), we can look at individual species and con-

Hemianax ephippiger(Burnt.), Somatochlora sider their status. alpestris (Sel.) and viridis (Vander L ); Of the 21 species recorded in categories

the 1-3 all 4 3 further species recorded only from but showed an increase in

Islands recorded of between 34 Channel namely fusca squares and 50%. This

(Vander L.). (Fabr.) and Cro- compares with an overall increase of 43%.

cothemis erythraea (Brulle). In categories 4 and 5. 10 species increased

In conclusion the British List comprises 52

species. 38 currently breeding ( Table II Kirby probably only in Ireland). 3 former

breeding species now extinct and 11 vagrants. % increase

recorded „ Cat. in recorded - The status of the British Odonata In the Species No. squares Provisional Atlas (HEATH. 1978) there are a ((1977-1979)1977-1979) total of 4977 species 10 km square post 1961

records for Great Britain (excluding Ireland BrachytronBrachylron pratense 4 27% and the total Channel Islands). This is pro- Ceriagrion tenellumlenellum 4 26% duced by counting all black dots for each Sympetrum sanguineum 4 23% The species. latest maps (produced February CoenagrionCuenagrionpulchellum 4 12% 1979) have added a further 2115 records which Libellula fulva 5 8% represents an increase of 43% in under two AeshnaA eshna isosceles 5 nil years. Lestes dryas 5 nil The total number of 10 km in the squares 94 Notul. Vol. No. odonatol., I, 5, pp. 85-96, June I, 1980

by between 47 and 133%, which probably scarce only where FMT is less than 0.6° C.

the The for of who indicates under-recording in past. Finally, those us have always

remaining 7 species, however, increased by wondered why Leucorrhinia dubia (Vander

between 0 and is has been from 27% only. 1 1 these species that L.) never recorded the splendid

must be considered vulnerable and of Dorset and the New Forest, it they are bogs may

listed in Table II. It is encouraging that none simply be that the winters are notcold enough.

of these has shown a real decline. Mention, Discussion of habitat requirements and

be of however, must made the situation re- ecology of individual species proved to be

Lestes This and and garding dryas. has not been lively informed only a brief summary

A number recorded in the mainland of Britain since of salient points can be given here.

and that of the of 1972, it is generallyfelt a combina- observers noted occurrence Platy-

ofclimatic conditions tion and major drainage cnemis pennipes (Pall.), generally a riparian

schemes Eastern have in England brought species, in large colonies on lakes. Dr M.J.

about its extinction. It remains a British Parr gave an explanation of the female colour

breeding species from Irish colonies alone. varieties of both Ischnura elegans and Ceria-

consider those tenellum that he Finally, we must species grion (de Vill.) explaining was

interested in which, even though they appear to be stable, hearing from any observers

in such small number of that about colonies of the latter which occur a squares possessed

vulnerable. PER RING & of the all red female they are still a high proportion rare

FARRELL (1977) considered species occur- form,erythrogastrum.

Dr N.W. Moore ring in 15 or less 10 km squares to be rare explained the attempts

enough for inclusion in the British Red Data he had made reintroducing C. tenellum at

Book for vascular plants. Four species of Wood Walton Fen N.N.R. in Cambridgeshire.

fall into this number Pools created in the acid dragonfly category (with were remnant peat

and introduced from of recorded squares), viz. Coenagrion mer- adults athreatened site in

curiale Somato- Dorset. The of adults (14), Aeshna coerulea (12), next generation appear-

ed chlora arctica (II), and Coenagrion hastula- two years later, but the colony was wiped

in tum (4). In conclusion, of the 38 breeding out 1976, possibly as a result ofthe drought.

Dr Moore species. 11 can be considered vulnerable and then went on to explain his dis-

of three warrant more intensive recording and study covery new colonies for Lestes dryas

in future. in Ireland, noting that the habitat, heavily

vegetated lowland dykes, was very similar

The distribution and ecology of the British to that where he had known the insect in

Odonatai— This discussion session opened Sussex in the I940’s.

the felt with consideration of the possible relation- Moving to Anisoptera, it was that

ship between distribution and environmental colonies of Brachytron pratense (Mull.) on

acid factors, particularly temperature. Overlays pools were the exception and that the

of environmental factors for use with dis- preferred habitat was lowland dykes. Details

tribution used of of maps (I.T.E.. 1978) were to were given surveys carried outon one our

illustrate the discussion. The most interesting most local species, Aeshna isosceles (Mull.),

factors appeared to be the February Minimum whose breeding colonies are threatened by

and July Mean Temperature isotherms (FMT drainage schemes.

and JMT). For example, Ischnura pumilio Graham Vick gave details of his Scottish

carried in which indicated (Charp.) and Coenagrion mercuriale (Charp.) survey out 1978 that

FMT A. do not occur where is less than 2.2° C, coerulea (Strom) was fairly widespread in

whilst C. hastulatum (Charp.) breeds only in Wester Ross, breeding in sheltered boggy

often with Somatochlora that part of Scotland where FMT remains pools arctica (Zett.) below and Leucorrhinia dubia. The indicator 0.6° C. Turningto our more widespread plant

for this species, C. puella (L.) and Calopteryx splen- species habitat was the sundew, Dro-

JMT below The showed that dens (Harr.) become rare as drops sera anglica. survey also

I5°C, and Ischnura elegans (Vander L.) is Somatochlora metallica (Vander L.) and Cor- 1. No. 85-96, June I, 1980 95 Notul. odonatol., Vol. 5, pp.

locali- dulia aenea(L.) were still present in Scotland valuable in pinpointingexact breeding and Eve Aeshna Harry reportedon acolony of ties of rare and local species.

about 150 miles cyanea (Mull.)near Inverness, north of its usual range. The Mapping Scheme

The final session took the form of an open

The collection and study of Odonata exuviae forum, the discussion ranged from such

the of the Channel (contributed by G.S. VICK) subjects as inclusion

four and how The study of exuviae offers advantages Islands in the scheme, vagrant species

the to the field odonatologist. Firstly, it allows they should best be indicated on maps and

all whether him to work in weathers, secondly it en- finally more detailed habitat informa-

the the ables him to determine precise breeding tion should be requested on recording

that habitat localities of particular species, an extensive card. It was generally agreed

collection can be made without affecting data would be desirable and that ultimately

number populations and finally, a of species there should be some more quantified ap-

often ob- rather than can be found which are difficult to proach to recording simple pre-

the lines serve as adults. sence or absence, possibly on of

It is important, when searching for exuviae, SCHMIDT (1979).

examine casual to vegetation very closely; Finally the master species map produced

This observation at a distance is rarely successful. by Bill and Bob Merritt was examined.

The of from stems emergent plants such as Reed- map indicated every species recorded

Bur Reed ( each 10 km Of the 1161 recorded mace (Typha spp.) Sparganium square.

7 spp.) and Yellow Flag ( Iris pseudacorus) are squares only 395 had records of species or

In shucks On the other total of 29 usually very productive. boggy areas more. hand, a squares

found the can often be on heatherand particularly had 20 or more species recorded; maxi-

ossi- 27 on stems of bog asphodel ( Narthecium mum currently standing at species from

For fragum). riparian species, particularly a square in Surrey. This county must be con-

gomphids, tree trunks and overhanging sidered the best recorded in Britain, with no

much favoured and it is often 20 or branches are fewer than 7 squares possessing more

worthwhile searching in bushes well above species. All remaining above 20 species

water level as some species move a consider- be found in southern England, squares are to able from distance water to find a safe emer- the most northerly being Berkshire.

gence point.

J„ 1978, Notul odo- Exuviae can be collected and stored References BELLE,

loosely in tobacco tins or pill boxes for natol. 1 (2): 31-32; - HEATH, J..[Ed ], 1978.

If later identification. they are dry then, with Provisional alias of the of the British

of few Inst. Ter- the addition a grains of naphthalene, Isles. Pi. 7. Odonata Dragonflies,

they will keep indefinitely. For identification restrial Ecol., Huntingdon; 1.T.E., 1978.

be detach the purposes it may necessary to Overlays of environmental and otherfactors

for examination. Dis- labium or lamellae closer for use with Biological Records Centre

This is achieved Hun- best by brushing relaxing tribution Maps. Inst. Terrestrial Ecol.,

the fluid or water on organ and then removing tingdon; LONGFIELD, C„ 1960, in. PS.

fine Lamellae best it with tweezers. are exam- Corbet, C. Longfield& N.W. Moore, Dragon-

and PER- ined by floating them in water trans- flies, pp. 33-54, Collins, London;

ferring them to plain glass microscope slides RING & FARRELL, 1977, British Red Data

or even glass 35 mm photographic slide Books. Pi. I. Vascular plants, Soc. Prom.

with mounts. The latter can then be used a Nat. Conserv.; SCHMIDT, E.. 1979, Odo-

slide projector and the lamellae examined natologica 8 (1): 63-76.

easily.

These used techniques were extensively in

Norfolk 1978 during survey work in both and

Scotland. On both occasions they proved in- Received November 19. 1979