Sunday, 29 December 2013

Glanvilles Wootton and beyond ...

The Dalean legacy (Part 2) ...



Black-veined White, Aporia crataegi, 10th June 1815 (Figure VI)

Dale's school days were spent between Enborne and his family home at Glanvilles Wootton in Dorset (Brown, 1980). For butterflies, the surrounding Dorset countryside was extremely productive territory. The Black-veined White, Aporia crataegi, which he had already come across at Enborne, was found at Glanville's Wootton in the years 1813, 1814 and 1815. The last specimen he took, a female, was on 10th June 1815. This is still in the Dale collection (Figure VI). This species then disappeared from the area and was not seen again at Glanvilles Wootton (Dale, 1890).

In his diary dated 1812, he notes a number of records for machaon, the Swallowtail, which was first seen at Glanvilles Wootton during 1808, and occurred commonly every year until 1816 (Brown, 1980). The last specimen he took was on Newland Common, which was close to the manor house, on 17th August 1815 (Dale, 1890). This is still in the collection, and has a date label in Dale’s handwriting (Figure VII). He also found two larvae on wild carrot (Brown, 1980). These records undoubtedly relate to the continental form, gorganus, which is highly mobile migrating throughout most of Europe breeding as it goes (Asher et al., 2001); thus making these records especially rare and notable. The British form, britannicus, being confined solely to the Norfolk Broads (Thomas and Lewington, 2010).


Swallowtail, Papilio machaon, 17th August 1815 (Figure VII)

During the first part of the nineteenth century, the Mazarine Blue, Cyaniris semiargus (referred to by Dale at that time as Papilio cymon), was not uncommon in a number of localities in England and Wales. Glanvilles Wootton appears to have played host to a strong colony. Dale first recorded it in his diary on 22nd June 1808. In addition, it was recorded once in both 1811 and 1812, it was common in 1813, 1814, 1815 (one being taken as late as 1st August) and 1816, scarce in 1817 and 1818, common in 1819, 1820 and 1821, scarce in 1822 and 1823, common in 1825 (twenty specimens being taken by Dale on 13th June), scarce in 1828, 1830 and 1831, common in 1834 and 1835, only one seen in 1836, a few in 1837, none recorded in 1838, scarce in 1839 and 1840, and in 1841 a pair on the 19th June, being the last ever recorded in Dorset (Dale, 1890). The exact locality where they occurred was in a section of the estate known as Mullett's Long Ground; a hayfield adjoining a copse, and situated between the Manor House and the Iron Age hill fort to the south known as Dungeon Hill. It was also taken on this hill in 1839. Other localities in Dorset where it was found include Middlemarsh, where one was taken by L. Denny on 4th August 1814; at West Parley, in the extreme southeast of the county in 1816, and again on 28th May 1833. Records also exist from Loders, near Bridport, on 27th July 1811, and at Powerstock and Has[z]elbury Bryan (Brown, 1980).

The following specimens (Figure VIII) are from the Dale Collection and are the same examples as figured on Plate 1 of E. B. Ford's, Butterflies, 1945.


Mazarine Blue, Cyaniris (Papilio cymon) semiargus, (Figure VIII)

In the summer of 1819, after graduating from Sidney Sussex College, Cambridge, Dale travelled to Whittlesea and Yaxley Meres in Huntingdonshire [Cambridgeshire] for the first time. His main objective was to look for the Large Copper, Lycaena dispar (referred to by Dale at that time as both Papilio and Chrysophanus dispar), which it was rumoured had been found there. He was unsuccessful, but whilst searching the Fens, Dale met a boatman, a Mr. T. Speechley, and he asked him to keep a lookout for a ‘red-looking butterfly’. On 4th August 1819, Speechley took a female dispar, the locality being a part of the fen called Trundle Mere. He wrote to Dale to inform him of his success and sent the dispar, together with a number of machaon in a box to a Dr. Leach at the British Museum, with instructions that they should be forwarded on to Glanvilles Wootton. This butterfly, the first to be taken in Whittlesea Mere (Brown, 1980), is still in the collection and bears the label: Whittlesea Mere, July, 1819 (Figure IX).

The following year, 1820, Dale commissioned Benjamin Standish to go to the fens and collect dispar for him. The locality, Trundle Mere, in Yaxley Fen, was shown to him by Speechley, the boatman. The trip did not appear to have been very successful, as Standish was there for six days in early August before he saw his first dispar. In all he took 12 specimens (Brown, 1980). Later in the month, on 21st August, he returned and took several more. The news soon spread around that this butterfly was worth money and two dealers came up from Cambridge and caught a large number, which they took down to London and sold for 3-4 shillings a dozen. The Standish family, which consisted of the father and two sons, were likewise very active. They were successfully charging ten shillings each for set specimens (Brown, 1980). As a cost comparison, farm labourers were earning around nine shillings a week (45p) in 1830 (Tolpuddle Martyrs' Museum, 2013). Dale himself went up to the Fens in 1826, 1827, and again in 1833 (Brown, 1980).

Dale had a correspondent, J. Henderson, of Peterborough, who wrote to Dale between 1826 and 1845. The following is an extract from a letter dated 4th March 1830: 'Such immense numbers of the larvae of L. dispar have been taken during the spring of 1828-29 that I fear the habitat will be totally destroyed. They are taken by every labourer residing near the Fen. I went to the Fens one day last summer when the insect was on the wing but found them very scarce indeed’, (Henderson, 1830). Later that spring, Henderson returned to the fen to look for larvae but was unsuccessful. Henderson reared dispar from larvae in 1835 and 1836. In June 1841 he sent Dale some pupae, but said that drainage was ruining the fen (Henderson, 1841). By 1843 it was confined to just one locality where the ground had not either been burnt or ploughed (Brown, 1980).


Large Copper, Lycaena dispar dispar, July 1819 (Figure IX)

It is of course all too easy to blame collectors for the demise of a particular species or race; although the greediness and irresponsible actions of some of them undoubtedly played a significant role in the loss of the beautiful Large Copper endemic to the British Isles, Lycaena dispar ssp. dispar, (Feltwell, 1995; Ford, 1945). In the case of the Large Copper, the changing fenland management and, in particular, the drainage and remodeling of the fens for agriculture, unquestionably played a significant role in its demise due to critical habitat loss. This, coupled with the lack of any protected status for the butterfly and the habitat it depended on, pushed the British subspecies into extinction in the Fenlands around 1851 (Dennis, 1977).

To the Lepidopterist the name of Dale will always be associated with the discovery of a butterfly new to Britain, Thymelicus acteon, the Lulworth Skipper. It is recorded, that on the 15th August 1832, Dale, having journeyed around twenty miles on horseback from Glanvilles Wootton, reached Durdle Door, near Lulworth Cove. Here he found considerable numbers of acteon along the cliff tops (Dale, 1832; Dale 1890; Brown, 1980). However, it was not until John Curtis reported Dale’s discovery in Volume 10 of his British Entomology, published in 1833, and named it the Lulworth Skipper, that the discovery was announced in print. Curtis wrote, ‘We cannot often hope to record the addition of a Butterfly to our British Fauna, but this species was discovered at Lulworth Cove in Dorsetshire, last August, by J. C. Dale, Esq. through whose liberality it now ornaments most of our cabinets: it was found upon Thistles, and was very local’, (Curtis, 1833). There are 22 specimens of acteon in the Dale collection, though it is difficult to determine exactly which of those are his initial discoveries; cabinet labels referring only to Burning Cliff, Lulworth and Swanage.

Dale passed away on the 6th February 1872. The last entry, in his diary covering the period 1860-1872, reads: ‘Wm. took G. leucophaearia and a Tortricodes his last writing’, after which his son Charles has written, ‘Feb 6th J. C. Dale died, thus at last his diary comes to an end after a brilliant career of 64 years. His end was peace. Aged 80 years and 2 months’ (Dale, 1872). He is buried at Glanvilles Wootton churchyard (Grave Index 366), the grave being just to the right of the entrance.



Dale's final diary entry before his death, 6th February 1872 (Figure X)

Dale’s entire collection is housed in the Hope Department of Entomology, Oxford. The Dalean collection was received at Oxford in 1906, after being bequeathed, with additions, by his son Charles William Dale (1852-1906). The original collection comprised of seven cabinets of British Lepidoptera, three cabinets of foreign Lepidoptera, five cabinets of British Coleoptera, 14 cabinets of British Hymenoptera and Diptera, four cabinets of Odonata and seven or eight cabinets of shells, birds eggs, etc.; the Odonata and Orthoptera have been transferred to modern cabinets in the general collection for safety. The collection contains a number of Lepidoptera types, described by J. Curtis and collected during Sir John Ross's second voyage in search of a north-west passage, 1829-1833, a few Selys Odonata types, some syntypes of Walker Chalcidoidea, a number of Haliday specimens, insects collected in France by Curtis in 1830, and some taken by F. Walker in Sweden and Norway in 1836. There are also four drawers of Wollaston beetles from Madeira, Cape Verde, Canary Islands, and St Helena, and five drawers of shells from the Atlantic Islands. Two Bronze celts, which had formed part of the Dale Collection, were transferred to the Ashmolean Museum in 1961 (Smith, 1986).

My thanks to Darren Mann and James Hogan of the Hope Department of Entomology for their generosity in providing time and unrestricted access to the Dalean collection, to Katherine Child for her image capture skills, and to Kathleen Santry, Head of Archival Collections and Librarian at the Oxford University Museum of Natural History, for providing access to Dale’s archives. To Phil Everitt and Peter Eeles, my thanks for their editorial comments and encouragement. To Tony Ladd, my thanks for his expertise in the black art of image manipulation. Finally, but by no means least, my thanks must go to James Charles Dale himself for leaving such an important treasure trove of entomological literature.

Images copyright OUMNH. Photographed by Katherine Child, Hope Department of Entomology, Oxford.


References:

1872. Entomologist’s Monthly Magazine. 8, pp. 255-256.
1872. Petites Nouvelles Entomologiques. Paris: E. Deyrolle. 49, pp. 197.
1892. The British Naturalist. 2: pp. 156.

Asher, J., Warren, M., Fox, R., Harding, P., Jeffcoate, G. and Jeffcoate, S., 2001. The Millenium Atlas of Butterflies in Britain and Ireland. Oxford: Oxford University Press, pp. 84-87.
Brown, S. C. S., 1980. J. C. Dale of Glanvilles Wootton. Dorset: Dorset Natural History & Archaeological Society, Dorset County Museum, pp. 1-15.
Curtis, J., 1833. British Entomology. 10: 442.
Dale, C. W., 1890. The History of our British Butterflies. London: John Kempster & Co, pp. 2-11, 56-58, 59-62, 217-222.
Dale, J. C., 1808. Calendar for the years of 1807-1812.
Dale, J. C., 1815. Entomological Diary for 1815.
Dale, J. C., 1832. Entomological Diary for 1808-1835.
Dale, J. C., 1842. Entomological Diary for 1835-1865.
Dale, J. C., 1872. Entomological Diary for 1860-1872.
Dennis, R. L. H., 1977. The British Butterflies – Their Origin and Establishment. Faringdon, Oxon: E. W. Classey Ltd, pp. 97-100, 104.
Feltwell, J., 1995. The Conservation of Butterflies in Britain (past and present). Battle, East Sussex: Wildlife Matters, pp. 55-69.
Ford, E. B., 1945. Butterflies. London: Collins (New Naturalist), pp. 142, 166-169.
Henderson, J., 1830. Letter to J C Dale dated, 4th March 1830.
Henderson, J., 1841. Letter to J C Dale dated, 14th June 1841.
Newman, E., 1872. The Entomologist. 6: pp. 56.
Smith, A. Z., 1986. A History of the Hope Entomological Collections in the University Museum, Oxford with lists of Archives and Collections. Oxford: Clarendon Press, pp. 72-73.
Thomas, J. and Lewington, R., 2010. The Butterflies of Britain & Ireland. Gillingham, Dorset: British Wildlife Publishing, pp. 39-42.
Walker, J. J., 1907. Some Notes on the Lepidoptera of the Dale Collection of British Insects, now in the Oxford University Museum. Entomologists Monthly Magazine. 43, pp. 93-101, 130-134.
Westwood, J. O., 1872. The Transactions of the Entomological Society of London.

Oxford University Museum of Natural History. www.oum.ox.ac.uk (Accessed, 26 November 2013).
Tolpuddle Martyrs' Museum. www.tolpuddlemartyrs.org.uk (Accessed, 26 November 2013).

Saturday, 28 December 2013

James Charles Dale

13th December 1791 to 6th February 1872

The Dalean legacy (Part 1) ...


James Charles Dale, circa 1864, (Figure I)

James Charles Dale (Figure I) was born at Iwerne Minster, near Blandford, Dorset, on the 13th December 1791. Born into a family of wealthy landowners he spent much of his adult life studying entomology. He was undoubtedly one of the most influential entomologists of his time, and his collections, spanning numerous insect orders, are probably the single most important and comprehensive to have ever been compiled in the British Isles.

In his early years, whilst attending Wimborne Greene Preparatory School, Dale was given a specimen of the Clifden Nonpareil, Catocala fraxini, reputedly taken by the Reverend W. Stovey (Rector of Hinton Martell, 1785-1799) at Boveridge, near Cranborne, around 1740, and whose son was a fellow pupil at the same school (Dale, 1808, cited in Brown, 1980). This specimen is still in the Dale collection (Figure II). When just nine years old, Dale captured a specimen of the Queen of Spain Fritillary, Issoria lathonia, at West  Orchard, near Sturminster Newton. The capture of this rarity, one of the very first to be taken in this country, and the earlier gift of fraxini, must have been a great encouragement for him to take up the study of entomology, a passion that would last his lifetime (Brown, 1980).


Clifden Nonpareil, Catocala fraxini, circa 1740 (Figure II)

After attending Wimborne Grammar School, in 1807 he was sent for private tutoring with the Reverend Thomas Shepherd, MA, who had a school at Enborne, near Newbury in Berkshire (Brown, 1980). In the same year Dale commenced his entomological diary, which was to continue every day without break for 64 years, the last entry being on the day of his death in February 1872.

In total, Dale’s daily journals and detailed books of records, which are accessible, by appointment, at the Library of the Oxford University Museum of Natural History (OUMNH), comprise an impressive 57 volumes. In addition, there are over 5000 letters from around 287 correspondents, excluding societies (Smith, 1986). They form one of the most important historical legacies left by any British entomologist. Reading through his diaries and correspondence, as I have been privileged to do on many occasions, has provided me with a captivating window into both his mind and era. Several pages from his journals of 1815 (Figures III and IV), 1832 (Figure V) and 1872 (Figure X), are shown below and highlight a number of British rarities and events including (i) Mazarine Blue (cymon), (ii) Swallowtail (machaon), (iii) Scarce Swallowtail (podalirius), most probably collected by the Rev. Dr. Abbott of Bedford, who died in 1817, and purchased after his death by Dale (Dale, 1890; Walker, 1907), (iv) Large Copper (dispar), (v) Bath White (daplidice), (vi) Large Blue (arion), (vii) his discovery, new to Britain in 1832, of the Lulworth Skipper (Thymelicus acteon), and, not least, his death in 1872.


Dale's diary for June 1815 (Figure III)


Dale's diary for July 1815 (Figure IV)


The discovery of Thymelicus acteon, 15th August 1832 (Figure V)

To be continued ...

Tuesday, 8 October 2013

100 not out ...

Acheta domesticus

Commonly known as the house cricket, Acheta domesticus occurs in the British Isles as a non-native species. It most likely originated in the hot, dry desert regions of Southwestern Asia, but has spread throughout the world. It is not well adapted to surviving the northern European winter, hence most British records come from artificial environments, such as those found in kitchens, bakeries, boiler houses, glasshouses (such as the female example below) and other areas where it is especially warm; though it can occasionally be found outdoors during the summer months on rubbish dumps and compost heaps, where the fermenting waste generates heat. There are very few outdoor records in the UK.

A. domesticus hides in crevices during the day and becomes active during the late afternoon and into the hours of darkness. The chirruping of the male, produced by rubbing the two front wings together, attracts the female cricket. After mating, several hundred eggs can be laid over a period of a few weeks. Whilst out of doors the eggs are usually laid in a shallow pit in soft earth, in artificial environments the eggs are typically deposited in moist debris in cracks and crevices. They are highly temperature sensitive, being inactive below 20°C, and developing through the nymphal stages most rapidly at around 35°C. High humidity is known to be important. With this in mind, the nymphs usually experience 7-9 moults before reaching maturity; which can take between 5 weeks to 4 months.

Though omnivorous scavengers, A. domesticus shows a preference towards vegetable matter. They themselves are commercially reared as food for pets such as amphibians, arthropods, birds and reptiles. In Thailand, they are also farmed for human consumption where they are commonly eaten as a deep-fried snack.


Friday, 23 August 2013

Mixed identity ...

Gynandromorphism

In Man, the destiny of the reproductive glands to develop into either male (testes) or female (ovaries) is determined by the sex chromosomes. The sex of all other parts of the body is controlled indirectly by hormones produced by these glands. These hormones circulate through the body via the bloodstream. The sex chromosomes that are present in all the cells play no part in this process. In insects, however, the situation is very different.

In the early cellular developmental stages of butterflies the sex chromosomes present in every cell decide and control the sex of that particular part of the body. The sex of a butterfly is initially determined by the number of Z chromosomes present in the zygote, the fertilized ovum: if two Z chromosomes are present it will be a male; if only one it will be a female. The zygote subsequently divides and each of these cells will go on to develop into right and left sides of the body. At every cell division there is always a very small possibility of a Z chromosome being lost in the process, causing an imbalance between the autosomes (any chromosome that is not a sex chromosome) and remaining sex chromosome. The resulting cell left with just one Z chromosome changes to being female in character and all further development is along those lines. An individual organism that contains both male and female tissue is termed a gynandromorph. This is the most commonly accepted method by which gynandromorphs arise.

Gynandromorphism in the Lepidoptera is most often associated with wing coloration. Should these features appear combined on the same wing as a mosaic it is referred to as a mixed gynandromorph. But sometimes an insect is bisected, such as the individual below, with one side of the body including the wings being either entirely male or entirely female. These remarkable and rare individuals are termed bilateral gynandromorphs. In many species of butterfly where extremes of sexual dimorphism occur, spectacular gynandromorphs can sometimes arise, particularly where one half is male and the other female.

My thanks to Alec Harmer for his assistance with this article ...


Brimstone, Gonepteryx rhamni (bilateral gynandromorph). Image copyright OUMNH.

Thursday, 15 August 2013

Chasing clouds ...

Clouded Yellow (Colias croceus)



The Clouded Yellow (Colias croceus) is primarily an immigrant to the UK, originating from North Africa and southern Europe, with numbers varying greatly from year to year. Each season, we normally see at least a few reaching our shores and, occasionally, they arrive in large numbers; such as the estimated 36,000 that appeared during 1947 when good numbers of much rarer migrants, such as Bath White (Pontia daplidice) and Pale Clouded Yellow (Colias hyale), were also recorded.

In more recent years, it has been shown that this species has successfully overwintered in the south of England. However, it is believed that the majority of individuals perish, since both larva and pupa of this continuously-brooded species are easily killed by damp and frosty conditions. In good seasons, C. croceus can produce up to three generations in the UK. In flight, the orange-yellow colour is quite distinctive, and unlike any other species. The pale helice form, occurring only in the female, is a creamy white, rather than yellow in colour and may lead to confusion with other similar species.

This strong-flying species always settles with its wings closed and so the dark borders on the uppersides of the wings are only clearly visible when in flight or when viewed backlit at rest. There is no elaborate courtship and, having mated, the female is subsequently able to lay an extraordinary number of eggs; up to 600 have been recorded from a single female.

Two females from 2013 above ...

Monday, 12 August 2013

Precious metals ...

Surrey Downland, 30-31 July 2013

The Silver-spotted Skipper (Hesperia comma) is a warmth-loving species. Its range contracted during the 20th century due to a reduction in grazing stock as well as the onset of myxomatosis in the early 1950s, which severely affected rabbit populations; the butterfly requiring closely-grazed chalk downland sites on which its primary larval foodplant, Sheep's-fescue (Festuca ovina), grows. Recent years have been more promising and this is one of the few species that is increasing its range. It is still relatively-local, with current strongholds being located in the Chilterns, Hampshire, the North Downs between Guildford and Reigate, East Sussex and south-east Kent. It occurs locally in my own county of West Sussex and is currently showing a positive trend for expansion into adjacent suitable habitat.

It is easily identifiable, since it is the only golden skipper found in the British Isles that has the distinctive white spots on the underside of the hindwings, which give the butterfly its name. Like other ‘golden’ skippers, the male is distinguished from the female by the sex brand on its forewings, which is a line of specialised scent scales.

H. comma is one of the latest species to emerge, typically not appearing until late July or early August, and it is then on the wing until early September. There is one generation each year. Like most skippers, this is a fast-flying species that flies close to the ground, and can be extremely difficult to follow when in flight. Both sexes spend the majority of their time either basking or feeding, and a wide variety of nectar sources is used. The butterfly will find the warmest patches of ground on which to bask, enjoying the warmth of paths, rabbit scrapes and other patches of bare earth, which have been baked by the sun. The males rest on suitable sunlit perches, and will investigate any passing butterfly, in the hope of finding a mate. If a virgin female is encountered, the pair exhibits a tumbling courtship, with the male eventually forcing the female to the ground where mating takes place. An egg-laying female locates a suitable patch of bare ground, such as a rabbit scrape, and then walks to the edge of the patch looking for a suitable location on which to lay a single egg.

A female at rest pictured below ...

Sunday, 11 August 2013

Coridon ...

Surrey Downland, 30-31 July 2013

Simply wonderful …


I recently spent two days, with good friend Nick Broomer, searching several areas of chalk grassland on the beautiful Surrey downland; our targets, the beautiful Silver-spotted Skipper and the enchanting Chalkhill Blue. We were not to be disappointed on either count.

Although Tuesday was accompanied by persistent rain for much of the day, an early morning arrival provided ideal conditions for searching the grassland for roosting butterflies; we were not disappointed and found many hundreds, probably thousands, of roosting Chalkhill Blues over much of the hill. This included a number of nice aberrant specimens including those pictured in the two images below, referable to ab. postcaeca, Bright & Leeds (1938). The first image shows a particularly well-marked male which we observed from shortly after emergence until its first flight. Wednesday started warm, and by midday large numbers of insects were on the wing. As the sun pushed through the clouds the numbers of Chalkhill Blues increased and we were privileged to witness a magnificent display as the air and ground around us turned blue as if covered in tiny sapphires. It is difficult to estimate actual numbers, though if I were pressed to do so, there were certainly many thousands and probably many tens of thousands on the wing; possibly many more. Although I didn’t witness the peak of the Sussex Chalkhill Blue explosion last year, Wednesday’s display was an event to remember ...

A privilege to have shared with a good friend …



Wednesday, 7 August 2013

Venom ...

Pirbright Common, 30 July 2013

Vipera berus


The European adder (Vipera berus) is the UK’s only venomous snake. Though painful, adder bites are rarely fatal; with only around 14 recorded cases of death in the last 150 years. As a result of its venomous bite, the adder is a much-maligned species in most of its range. However, they are generally shy, timid and non-aggressive, and bites are most likely to occur when the snake has been disturbed or deliberately antagonised; they should therefore not be intentionally handled. Professional medical help should always be sought as soon as possible after any bite.

V. berus is the most northerly member of the Viper family and is found throughout Britain right up to the north of Scotland. It is not found in Ireland. It shows a preference for open habitats such as heathland, downland, moorland, open woodland and sea cliffs; habitat complexity being essential for different aspects of its behaviour. They rarely stray into gardens.

It is easily recognised by a dark 'zig-zag' stripe along its back. There is also a row of dark spots along each side and a ‘V’ or ‘X’ shape on the back of the head. Its orange-red eyes and vertically slit pupil are also diagnostic. Background colours vary from grey-white in the male, to shades of brown or copper in the female (pictured above). Completely black specimens are occasionally described. They typically grow to around 65cm in length, though can reach up to 90cm, and generally have a rather stocky appearance. Mating takes place during April and May and female adders incubate their eggs internally (ovoviviparous), rather than laying shelled eggs like the grass snake. Adders 'give birth’ to live young in August or September. Their litters ranging in size from 3 to 20 with the young staying with their mothers for a few days. They feed largely on small mammals such as mice, voles and shrews. Lizards, frogs, newts and nestling birds are also taken.

Adders are protected by law in Great Britain. It is illegal to deliberately kill, injure or sell wild adders.

Thursday, 27 June 2013

Black magic ...

Bernwood Meadows, 27 June 2013

The Black Hairstreak (Satyrium pruni) is one of the rarest and most elusive butterflies in Britain. It is also one of the most recently discovered (1828), due to the similarity with its close cousin, the White-letter Hairstreak (Satyrium w-album).

S. pruni is not a great wanderer and an entire colony will often restrict itself to a single area within a wood, despite there being suitable habitat nearby. This inability to colonise new areas at a pace, in balance with habitat loss, may partially explain the scarcity of this species. This butterfly has a very restricted distribution that is confined to a line of clays between Oxfordshire in the south-west and Cambridgeshire in the north-east. Colonies are typically located in small woods or nearby hedgerows, where blackthorn, the main larval foodplant grows. Sites are located in sheltered but sunny positions and typically have a southerly aspect to them.

The adult stage has an extremely short flight period, being typically seen in the last two weeks of June and the first week of July. There is a single generation each year. Upon emergence, the adults spend much of their time resting high up on maple, ash or the larval food-plant, crawling over leaves and twigs, in search of aphid honeydew from which they feed. Primarily an arboreal species they will occasionally come down to feed on various nectar sources including man made attractants. As with all hairstreaks, when active, they are extremely difficult to follow. To make matters worse, the Black Hairstreak is often found in the company of both White-letter and Purple Hairstreaks and distinguishing these three species in flight is almost impossible.

A male feeding pictured below ...


Saturday, 22 June 2013

Vespa crabro ...

West Sussex, 20 June 2013

Royal appointment ...

The European hornet, Vespa crabro, is the largest European eusocial wasp; the queens averaging around 3cm in length (the queen pictured below measured 3.5cm, with a wingspan of 5.5cm). With the exception of the Median Wasp, Dolichovespula media, whose queens resemble small worker cast hornets in size and colour (D. media is yellow and black with small areas of red whereas V. crabro is a brown, red and yellowish-orange species lacking any deep black markings), it is unlikely to be confused with any other species.

Once only common in central southern England, it has now extended its range from Cornwall to Kent and northwards into Yorkshire. It has also been recorded from The Isles of Scilly, Isle of Wight and the Channel Islands. It is found in many lowland habitats, but is particularly associated with ancient deciduous woodland.

Queens emerge from their over-wintering sites in early April and nests are initiated, usually in hollow trees or similar cavities, in May with the first workers generally appearing around late June to early July. New queens and males, which emerge from the nest from September to October, mate and then disperse, with the males dying and the newly-mated queens seeking over-wintering hibernation sites. Back at the nest, which may persist into November in mild seasons, the old queen and remaining workers eventually die-out. V. crabro predates on a number of invertebrate species including other social wasps, honey bees, flies, butterflies, moths (hornets can forage in moonlight) and spiders. Prey is often taken from flowers and the vegetation of trees. In late summer and autumn, workers are sometimes attracted to exudations from deciduous trees; particularly oak. Workers, males and new queens will also visit Ivy, Hedera helix, blossom for nectar.



Tuesday, 18 June 2013

Big game ...

Iping Common, 17 June 2013

There are five species of Tiger Beetle in Britain: Cicindela campestrisCicindela hybridaCicindela maritima, Cicindela sylvatica and Cylindera germanicaOf these, the Heath Tiger Beetle (Cicindela sylvatica) and the Cliff Tiger Beetle (Cylindera germanica) are both UK Biodiversity Action Plan (UK BAP) species; meaning they are species of conservation concern and action is being taken to protect and conserve them and their habitats. Two species have been recorded in Sussex. These include Cicindela campestris and Cicindela sylvatica.

The commonest, and possibly the most attractive of the British species, is the beautiful Cicindela campestris, the Common or Green Tiger Beetle. C. campestris is a fast, long-legged, agile predator that is easily recognized due to its iridescent green and purple colouring, along with its distinctive yellowish spots on the elytra. The adults, which can be seen from April to September on dry heaths and other sandy places, fly and run actively in the sunshine.



Saturday, 15 June 2013

Grizzlies ...

West Sussex, 10 June 2013

The tiny Grizzled Skipper (Pyrgus malvae) typically occurs in small colonies of less than 100 individuals. It is found in England south of a line extended from West Gloucestershire in the west to North Lincolnshire in the east, with strongholds in central and southern England. There are scattered colonies further north and in Wales. This species is absent from Scotland, Ireland, the Isle of Man and the Channel Islands. Despite the suggestion in its specific name, malvaeP. malvae larvae do not feed on flowers of the mallow genus; though several closely related European species do feed on Malvaceae.

The adult emerges in late April, the first of the British Skipper species, and usually flies until the end of June. There is one generation each year, although there may be a small second brood in some seasons, when conditions are favourable.

This is a warmth-loving species, and both sexes bask in the sun for long periods, typically on a stone, leaf or bare earth. This is an active insect which will fly at most times the day, and even into the evening, if conditions are warm enough. The male is somewhat territorial and will chase any butterfly, irrespective of size, from its area. Females entering the territory are courted for a short period and, if the female is receptive, pairing occurs. The butterfly can be found roosting on heads of flowers and grasses during cool weather and at night.






Wednesday, 12 June 2013

New definition required ...

West Sussex, 3 June 2013

DINGY: Adjective: Gloomy and drab.

Despite its name, a freshly-emerged Dingy Skipper (Erynnis tages) reveals a most delicate pattern of browns and greys that is undoubtedly quite beautiful. Despite its decline due to changes in farming practice, this is our most widely-distributed Skipper. Colonies can be found throughout the British Isles, including northern Scotland and Ireland (ssp. baynesi) where, although scarce, is found on outcrops of limestone. It’s strongholds are in central and southern England.

And I almost didn't take my camera ...


Tuesday, 4 June 2013

Serpentes ...

West Sussex, 1 June 2013

Natrix natrix (Linnaeus, 1758)


The Grass snake, Natrix natrix, is Britain's largest native terrestrial reptile, and probably its most common species of snake. It is non-venomous and completely harmless to man; and rarely bites, even when handled.

With regards to the British subspecies, helveticaN. natrix is most easily identifiable by the interlinked black and yellow collar, which usually forms a band or ring immediately behind the head. The upper body is typically olive-green, olive-brown or greyish in colour, with a variable row of black bars along the sides; occasionally with smaller round markings along the back in double rows. The ventral scales are off-white or yellowish, with dark triangular or rectangular markings. The face has marked black bars on each side below the eye and these provide a key method of individual identification. Melanistic and albino forms are rare but occasionally arise. The sexes are similar in appearance, although females are usually larger. Males can be identified by the presence of a swelling at the base of the tail and by the fact that they have longer tails relative to females. In addition, the head of the female is much more pronounced in being triangular in appearance with the eyes deep set into the cheeks; whereas the male has an altogether more slender head with eyes that often protrude beyond the line of the face and jaw. The majority of females also tend to possess two postocular scales (behind the eyes), as opposed to the males three. The female may grow up to 1.2 metres in length (snout to vent); however, more mature individuals have been reported up to 2 metres in length. The male is generally much smaller in comparison, and individuals of around 600mm are usually among the largest specimens recorded.

Ponds, lakes and rivers are their preferred habitat. They are strong swimmers. Not only are features such as bank-side vegetation important to provide cover against their predators, there must also be readily identifiable passages of ground cover in the form of ditches, hedges or banks of brambles which lead up to the banks. If such passages are removed from the surrounding environment, then the frequency at which N. natrix will visit a particular water body will reduce.

From March, when the snakes emerge from hibernation, until mid may, they eat large quantities of small fish; mainly because these are spawning during this period and are easier for the snakes to catch amongst the weedy fringes of water bodies. From May to early July, the diet emphasis falls onto newts, and again, this is because the newts own life cycle doesn’t include a land-borne phase until after July. From July, N. natrix gradually disperses away from ponds and into forest clearings, wooded copses and longer grasses / ground cover and a higher number of frogs and toads will then be taken as a result. The frogs and toads themselves have generally moved away from the ponds by April, although some are obviously predated upon between the cross over of snakes arriving at ponds in spring and while the frogs or toads are migrating away from them. Nests of very young chicks such as moorhens are sometimes consumed (mainly to supplement an otherwise restricted diet), as are mice and voles, especially by the more mature female snakes, but these incidents are rare.