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The Society's Insect Conservation Committee is chaired by Prof Jeremy Thomas OBE and oversees our conservation activities. We also publish an international journal dedicated to conservation and diversity issues: Insect Conservation and Diversity

You can read about the Society's newest conservation initiative below.

The Royal Entomological Society’s nature reserve for insects

The Royal Entomological Society jointly owns Daneway Banks SSSI with the Gloucestershire Wildlife Trust. Daneway Banks in the Cotswold’s Sapperton Valley and its 40 acres of prime limestone downland, together with 2.5 acres of ancient beech, yew, hawthorn and hazel woodland, have long been considered exceptional for biodiversity even by the high standards of Cotswold grasslands. It is a very special Site of Special Scientific Interest, famed not only for supporting large populations of Endangered Species but also for the sheer variety of scarce, local or unusual insects and plants that breed in remarkable abundance within its boundaries.  In addition, in 2014-17 it supported the second largest population in the UK (and possibly the world) of the Large Blue butterfly, our only species of insect to be listed as a globally ‘Endangered Species’ by the International Union for Conservation of Nature.

Daneway Banks was formally launched as a jointly owned nature reserve by HRH the Prince of Wales in July 2016. 

HRH The Prince of Wales seated with Ellie Harrison (GWT President) on a bench carved with illustrations of the Large Blue butterfly’s life cycle, during a tour of Daneway Banks with Prof Jeremy Thomas, Chairman of the RES Conservation Committee (centre) and Gloucestershire Wildlife Trust CEO Roger Mortlock. Image: Paul Nicholls
Adult Large Blue laying eggs on the flowerbuds of wild thyme. Image: David Simcox


From the RES Presidencies of Charles (1915-16) and Walter Rothschild (1921-22) onwards, The Royal Entomological Society has established an enviable record in advocating and pioneering the conservation of insects. In its first half century, the emphasis was on re-establishing the extinct Large Copper butterfly to the British Isles, protecting the Large Blue, and working alongside Charles Rothschild’s fledgling Society for the Promotion of Nature Reserves, the precursor of today’s County Wildlife Trusts. With the growth of these and other dedicated conservation societies, and the establishment in 1949 of the government’s Nature Conservancy, the RES’ focus shifted towards influencing policy and good practice rather than carrying out practical conservation itself. For example, in the 1960s the RES established and serviced the ‘Joint Committee for Conservation for British Insects’, and remains a key partner of its successor ‘Invertebrate Link’, an enormously important forum for co-ordinating, nurturing, influencing and promoting the conservation of insects.

During the 1970s-80s the RES oversaw and hosted the selection and publication committees for the British Red Data Books: Insects. More recently, the RES has been the global leader in propagating the scientific knowledge that underpins insect conservation, exemplified by two ground-breaking international symposia: The Conservation of Insects and their Habitats (1989) and Insect Conservation Biology (2003), and its journal Insect Conservation and Diversity (2008-).

Notwithstanding this shift in emphasis, RES Council and its Conservation Committee have explored an aspiration in recent years that our Society should also, in some measure, return to its roots by making a significant contribution to practical conservation through owning and maintaining a show-case nature reserve that was of national or international importance for insects. The opportunity arose in 2014, when the Gloucestershire Wildlife Trust approached the RES to explore co-ownership of Daneway Banks, a site they had rented since 1968 but which was now offered for sale. In addition to halving the capital cost, GWT would benefit from the expertise of RES Fellows in management recommendations, monitoring and scientific and educational input, whilst RES would help save and (co-)own a reserve that not only made a tangible contribution to insect diversity but was also amenable to entomological research and educational activities.

Information about the site

The wildlife of Daneway Banks SSSI     

Consisting of a series of south-east facing slopes and flatter strips overlying Jurassic limestone and some Fuller’s Earth, Daneway Banks is a beautiful downland as well as a species-rich one. The main sward is classed as Bromus erectus - Brachypodium pinnatum grassland (National Vegetation class CG5a), interspersed with patches of scrub and woodland, and occasional cliffs and scree from small abandoned quarries.

Welsh Mountain ponies (and Norfolk Horn Sheep) from the Butts Ram Rare Breeds Centre graze Daneway Banks from autumn to early spring. Image: Jeremy Thomas

From mid-autumn to spring, Daneway Banks is grazed by Norfolk Horn sheep and Welsh Mountain ponies from the nearby Butts Farm Rare Breeds Centre, themselves an attractive feature of the site. By late winter the sward is predominantly short (with scattered taller patches) revealing an ant-scape of thousands of Yellow Meadow ant hills – known locally as emmett casts - seen at their best when casting long shadows in the winter sun. The land is then left ungrazed through spring and summer, allowing a succession of flowers to bloom and set seed, and for insects to breed, in a sward that remains sparse and heterogeneous on its infertile soils. By mid-April, much of Daneway turns pale yellow with the blooms of cowslips matched by Kidney vetch on thinner soils.  These give way, respectively, to the deeper yellow and pinks of rock-rose and wild thyme during June, and by high summer marjoram and harebells in abundance make a purple-blue backdrop to the cerise of pyramidal orchids.

Some of the less common plant species on the site

Interspersed among these prominent species grow a diversity of other calcareous plants. Of special interest are two national rarities, Cut leaved Germander Teucrium botrys and Cut-Leaved Selfheal Prunella laciniata.  Other Red Data or Nationally Notable plants include Frog Orchid Coeloglossum viride, Fly orchid Orchis insectifera, Musk orchid Herminium monorchis, Green-winger orchid Anacamptis morio (in hundreds), Greater butterfly orchid Platanthera chlorantha, Slender bedstraw Galium pumilum, Dwarf rock-bristle Seligeria pusilla, Angular Solomon’s-seal Polygonatum odoratus, Meadow saffron Colchicum autumnale, Hound’s-tongue,Cynoglossum officinale, Dwarf spurge Euphorbia exigua, and Sainfoin, Onobrychis viciifolia . Most, if not all, of these plants have increased, and in some cases reappeared after long absences, under ‘Large blue management’.

Some of the rarer insect species on the site

The diverse flora coupled with a warm but heterogeneous microclimate and soil structure supports an abundance of common and rare insects, which in turn are host to predatory and parasitic species. Insect life is noticeably abundant on the site. Among known rarities breeding in good numbers are four striking Diptera:  Inane hoverfly Volucella inanis, Dotted bee-fly Bombylius discolor, Western bee-fly B. canescens and the Downland Villa Villa cingulata. The last is especially welcome since it was not reported from the UK during the second half of the 20th century, but has recently reappeared on a handful of calcareous sites, mainly in the Chilterns. The population at Daneway is exceptionally large, and the striped adults are readily seen flicking eggs onto the bare ground of paths and scrapes during high summer.

Other notable insects include the Hawthorn jewel beetle Cionus nigritarsis, Cryptocephalus aureoles, Variimorda villosa, glow-worm Lampyris noctiluca, Roesel’s bush-cricket Metrioptera roesolii, and the largest known UK population of the ant Myrmica lobicornis. Moths include the Knot grass Acronicta rumicis, Forester Adscita statices, Drad looper Minoa murinata, Shaded broad-bar Scotopteryx chenopodiata and Sulphur pearl Sitochroa palealis. Notable butterflies are the Small blue Cupido minimus (in abundance) Dark Green and Small pearl-bordered fritillaries (the latter breeding in small numbers extending from the neighbouring Siccaridge Wood reserve), Dingy skipper, Grizzled skipper, and regular sightings of Marsh fritillary from a permanent colony nearby. The Duke of Burgundy Hamearis lucina is currently absent from Daneway but expected to return to breed on the abundant cowslips, many of which now exist in optimum growth-forms for its specialist larvae.

Rare vertebrates are not a feature of Daneway banks, although the more widespread species may be common. The site supports Common toad Bufo bufo, Grass snake Natrix natrix, Adder Vipera berus (in high numbers for the Cotswolds), Slow-worm Anguis fragilis, and Common lizard Zootoca vivipara. Breeding Birds include Skylark Alauda arvensis, Yellowhammer Emberiza citronella, Song thrush Turdus philomelos and Bullfinch Pyrrhula pyrrhula. Buzzards are ubiquitous overhead, and the downs frequently echo to the croak of raven. Dormice breed across the road but have yet to be reported from Daneway.

The Large Blue butterfly, Maculinea arion

The Royal Entomological Society has a long association with the Large Blue butterfly: it is thus fitting that we now (co-)own a major site. The classic experiments by E.B. Purefoy, T.A. Chapman and F.W. Frohawk that revealed how its larvae, after briefly feeding on thyme flowerheads, live underground as social parasites eating Myrmica ant grubs, were first published in Trans./Proc. Ent. Soc. Lond. in 1915-19. Then in 1931, when insect conservation was almost unknown, the RES established the ‘Butterfly Valley’ reserve at The Dizzard, Cornwall, to protect one of the Large Blue’s finest sites. For 8 years butterfly collectors were excluded, but unfortunately the local farmer Mr. Samwin was also barred from swaling (gorse-burning) and grazing the site, and the colony became extinct. Undaunted, the RES led the calls for constraint among collectors throughout the 1940s and ‘50s, and in the 1948 sponsored a survey of West Country sites by Capt. R.A. Jackson. In 1963, represented by Graham Howarth, the RES was one of five founders of The Joint Committee for the Conservation of the Large Blue Butterfly, the consortium that still leads the national programme to restore this species. And in 2002, the Society commissioned a portrait of the Large Blue as a present to its patron, The Queen, in celebration of her Golden Jubilee.     

The Cotswolds was one of three main regions (of six) where the Large Blue butterfly bred before its extinction as a UK species in 1979. Although a classic collecting ground for this most coveted of butterflies, the credentials of only 11 out of c.32 Cotswold ‘sites’ rest on more than a single record, and just four of them, including Daneway Banks, have records spanning more than 50 years. The earliest account for it at Daneway, or indeed anywhere in the Cotswolds, was by R.E. Trye in 1858; the last definite one is for 1947, although it probably persisted until 1951 when, according to Peter Crow, “a schoolmaster from Minchinhampton helped ‘clear out’ the locality by inviting parties of boys at the school to Large Blue catching excursions”. In fact collectors are unlikely to have been more than the final straw for a population that, like all others, was in steep decline due to the progressive abandonment of the Large Blue’s unproductive swards by farmers, and later through the loss of rabbits to myxomatosis.

The story of the Large Blue larva’s chemical and acoustical mimicry of – and dependency on - a single species of Myrmica ant rather than any of its three more common congeners (or Lasius flavus) as was previously supposed are told in RES symposium volumes 19 and 21.

The story of the restoration of appropriate habitat for the Large Blue by a consortium of 14 scientific and conservation organisations, directed by David Simcox and Jeremy Thomas, to currently c. 100 UK nature reserves and other sites, and the successful re-introduction of a near identical race of Large Blue from Sweden in 1983 (Devon) and 1992 (Somerset and Gloucestershire), is also too familiar to describe in detail here. By the time of the 25-year celebration of its re-establishment, the butterfly had spread to over 30 sites, mainly in Somerset, and although most were small satellite colonies, the core populations were exceptionally large for this rarity, exceeding known numbers anywhere else in the world.

We struggled, however, in the Cotswolds. There, the early introductions to Rough Banks and Barnsley Warren failed because the adult butterflies emerged too late to synchronise with flower-bud production of thyme, leaving the females to oviposit on occasional late-flowering plants growing in the coolest spots within sites, i.e. the only places where M. sabuleti was absent! We had taken them an isotherm too far. In Somerset, where spring and summer local climates were ~1.5 oC cooler than the source sites in Sweden, the synchrony was imperfect but adequate; in the Cotswolds, where temperatures were a further half degree cooler, it was not.           

Large Blue larva being ‘milked’ for secretions by a Myrmica sabuleti worker prior its larva’s adoption into the ant nest. Daneway Banks. At this stage it weighs c 1% of its final body mass. Image: David Simcox

Daneway Banks always seemed a more promising site for restoration. At the nadir of under-grazing in the 1970s-80s, 10% of its thyme plants still remained within foraging range of Myrmica sabuleti, nowhere near enough for the Large blue yet among the highest then in the Cotswolds. Gradually, ant densities increased and thyme spread, reaching 65% co-occurrence in 1998 and >90% since 2010 under GWT’s targeted grazing. David Simcox’s and my trial introduction of Large blues to Daneway, from a thriving colony on Somerset Wildlife Trust’s Green Down, initially produced promising results in 2001-04, with growth matching model predictions. However, continuity of grazing proved elusive with the then grazier, and ceased after a severe incidence of bovine TB, causing the ant to decline and the butterfly to disappear. A second introduction by Simcox and Sarah Meredith in 2010 was successful. Exemplary management under a new grazier has achieved optimum habitat at Daneway, and by 2014-16 it already supported the second largest population of Large blue in the country, with an estimated 101, 831 eggs laid in 2016, equivalent to roughly 4,000 adults. In addition to the improved habitat, the butterfly had itself adapted better to UK conditions by 2010 after 18 generations of selection on Green Down. Adult emergences now occurred earlier and synchronised precisely with Thyme flowering. During the same period, the emergence simultaneously shifted c. 14 days later on a second site to which it had spread in Somerset, after similarly strong selection to oviposit on Marjoram - its early foodplant in southern Europe - which flowers later than thyme. We used both colonies as sources for the 2010 introduction, since both plants are widespread on Daneway, roughly doubling the number of accessible Myrmica sabuleti nests than if thyme alone were exploited. As well as increased numbers, this results in an extended emergence with an interesting double peak on Daneway, where roughly equal numbers of eggs are now laid on each plant.  Another adaptation from the Somerset populations has been of increased adult dispersal by this normally sedentary species as it spread by stepping-stone colonisation to new sites across the landscape. This attribute, together with back-up plans for emergency grazing if ever needed, make us confident of long-term success on Daneway and wider afield in the Cotswolds, as other reserves receive similar management. These, as in Somerset, should support a meta-population of Large blue colonies, in this case with Daneway at the core, with each able to repopulate its neighbours by natural dispersal should a local loss occur.       

Visiting Daneway Banks

Fellows and Members are encouraged to visit Daneway Banks, which is located at OS grid reference SO937034, half a mile west of the village of Sapperton and 1 mile north (as the insect flies) of the A419, midway between Stroud and Cirencester. The main entrance is 250 yards north of the Daneway Inn pub. Please note that apart from in Sapperton, very few parking spaces are available except in the pub carpark, which visitors are welcome to use so long as they also patronise the pub, which provides excellent food. The site is especially busy during the main Large Blue flight period, from mid-June to mid-July.

Please submit any records of insects (and other wildlife) seen to Luke Tilley ( To avoid confusion and potential embarrassment, it is essential to obtain prior permission before taking collecting equipment onto the site, and since it is an SSSI, formal permission is also required from Natural England to collect or remove specimens. For private visits, please also keep to the footpath or the additional routes indicated on the site map. Despite some inevitable constraints due to the vulnerability of this site, please visit and enjoy our wonderful new reserve.

Springtime at Daneway Banks SSSI. Image: Jeremy Thomas

The RES proudly co-owns Daneway Banks with the Gloucestershire Wildlife Trust (GWT) and would like to thank the many RES Fellows and staff, and GWT members and staff that helped and took part in the process of approving and acquiring Daneway Banks. Particular thanks must go to Prof Jeremy Thomas (RES Conservation Committee, Chair), David Simcox and Sarah Meredith (Large Blue Project Consortium) and Grundon - waste management, environmental and recycling solutions.

More information about Daneway Banks SSSI can be found on our partner’s website, the Gloucestershire Wildlife Trust

For more information about the Large Blue butterfly, please visit UK Butterflies.

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