A Review of British Lepidoptera for 1970

A REVIEW OF BRITISH LEPIDOPTERA FOR 1970 BARON DE W O R M S

THE early weeks of 1970 followed very closely the pattern of its predecessor with very little wintry conditions. In fact most of January and February were extremely mild with all the early geometer moths appearing well up to Standard times, but the lepidoptera received a severe setback inthefirst half of March which was unusually cold with heavy snowfalls during its opening days.

However, the Yeilow-horned (Achlya flavicornis Linn.) was out by the middle of the month, though the sallow blossom was only just starting at the end of March which brought with it one of the chilliest Easter periods for many years, but during a few warmer days in the third week of March the Orange Underwing (Archiearis parthenias Linn.) was well on the wing in East Kent. The first hibernating butterflies in particular the Brimstone (Gonepteryx rhamni Linn.) also began to fly at this period, rather a late date.

April proved a comparatively mild month which saw the appearance of the first White butterflies during its final week, but real summer arrived during the first ten days of May with temperatures well into the 70s. All the spring butterflies came out with a rush, including the two Pearl-bordered Fritillaries (Clossiana euphrosyne Linn, and C. selene Linn.) which were both more numerous than usual. A feature at this period in May was the number of hibernating females of the Pale Pinion (Lithophane socia Hufn.), in parts of southern England, seldom a common insect at this time of the year. The Orange-tip (Anthocharis cardamines Linn.) was also quite plentiful during May, which did not produce any migrants of note, except for a few Painted Ladies (Vanessa cardui Linn.) which were far from plentiful.

June opened with some glorious weather. In fact the first two weeks proved to be one of the wärmest periods in recent years with the thermometer in the 80s daily and even reaching the phenomenal figure of 100°F. in the shade in the Lake District on 1 Ith June. This remarkable spell brought forth all the summer lepidoptera in a spate. A good many local species among the moths were in abundance, in particular the Alder Moth (Apatele altii Linn.) and the Beautiful Snout (Bomolocha fontis Thunb.).

The butterflies too appeared in unusual quantity over most of the country, though it was largely the southern counties which provided the more interesting species. The Holly Blue (Celastrina argiolus Linn.) had another good season with relative abundance over all its ränge. The latter part of June though less settled than the first half of the month, saw a remarkable emergence of some of the Hairstreak family. In its restricted haunts in the Midlands, the Black Hairstreak (Strymonidia prutii Linn.) was more numerous than it had been for a great many years, while its near relative

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the White-lettered Hairstreak (5. w-album Knoch.) was in quite prodigious numbers in early July, appearing in a number of localities where it had not been observed before. Even the Purple Hairstreak (Thecla quercus Linn.) was also in exceptional plenty in oak woods all over the south. The larger fritillaries too were equally plentiful, especially the Dark-green (Argynnis aglaia Linn.), even in Ireland, while in the New Forest area, the Silverwashed (Argynnis paphia Linn.) and its female form / . valesina had a very prolific season. It was another good year in succession for the Purple Emperor (Apatura iris Linn.) in most of its special haunts in the southern region of the country. Throughout July there was a remarkable butterfly population reported in most parts of England and the moths too were in no less profusion at this period. Such species as the Blackneck (Lygephilapastinum Treits.) was swarming especially on the Suffolk coast. It was also a good year for most of the Wainscot family including the White-collared Wainscot (Nonagria neurica HĂźbn.), a Suffolk speciality. August was for the most part yet another fine month bringing with it a very prolific emergence of the late Blues, chiefly the Chalk-hill (Lysandra coridon Poda) which was in much better numbers than usual on many southern downland regions as also was its near relative the Adonis Blue (L. bellargus Rott.) towards the end of that month. In spite of this comparative abundance of some of the most local resident species there was a distinct lack of the commoner migrants, those which normally arrive at this time of year. In fact it is doubtful if there was an authentic record of the Clouded Yellow (Colias croceus Fourc.) for the whole extent of the southern counties. The Red Admiral (Pyrameis atalanta Linn.) too, was quite a rarity except in the extreme south-west and the same can be said of the Painted Lady ( Vanessa cardui Linn.) whose presence was very sporadic throughout the country this season. However, the late summer and early autumn which brought some very warm weather, provided, as so often at this time of year a fair number of the migrant species. Foremost among these was the Convolvulus Hawk Moth (Herse convolvuli Linn.) of which there was quite an influx in the south-western areas with a sprinkling in the more easterly regions of the British Isles, though not many seem to have penetrated far northwards. At the same period several of the Death's Head (Acherontia atropos Linn.) were reported in the south as well as a few of the little Vestal (Rhodometra sacraria Linn.) and the Small Mottled Willow (Laphygma exigua HĂźbn.), but the Common Silver-Y (Plusia gamma Linn.), so often in great plenty in the later months of the year, was, in fact quite a rarity.

September as usual added a few migrants, notably a Camberwell Beauty (Nymphalis antiopa Linn.) in the London area, an American Painted Lady (Vanessa huntera Fab.) in North Devon, and a Clifden Nonpareil (Catocala fraxini Linn.) in Hampshire, but October did not bring with it any spectacular immigration

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such as happened in 1969, though a few of the Delicate Wainscot (Leucania vitellina Hßbn.) and the White-Speck (L. unipuncta Haworth) appeared during this month in the southwestern approaches. It was during late September that further specimens were taken on the east coast of a remarkable and large noctuid moth of which an example was first noted in this region in 1968, though its actual identity was only established somewhat later. It might be termed the Large Frosted Orange (Gortyna lunata Freyer) which is new to the British list. However, it is interesting that abroad it is said the species feeds almost exclusively in the sterns of the Hogs Fennel (Peucedanum officinale) which according to the botanical maps is a plant with a very restricted ränge on the coasts of Essex and Kent.

To sum up, 1970 with several very warm periods proved a very good season for most of our indigenous butterflies and was a fairly prolific one for the moths as well, but somewhat unaccountably it turned out one of the leanest years for the migrant species since the last war.

Baron de Worms, M.A.,

F.R.E.S., Three Oaks, Shores Woking, Surrey.

Road,

CONSERVATION OF REPTILES AND AMPHIBIANS J . W . STEWARD

IN recent years it has become widely recognised that the wildlife of this country, as of many others, is being increasingly threatened.

This is seen as part of a general problem of protecting the environment as a whole, and already a fair amount of research and a number of specific measures have been instigated to this end.

Proper research is obviously of paramount importance at this stage, since suitable planning must be based on adequate information, and the margin of safety for many species is already too narrow to allow for serious mistakes. The British reptiles and amphibians have suffered more than is generally realised, the amphibians particularly by pollution and destruction of breeding sites and all of them by widespread changes in their habitats.

Populations in most areas have declined considerably this Century, and in some places disappeared altogether. Realising this, the British Herpetological Society in 1969 set up a Conservätion Committee to study the position and formulate proposals for ensuring the survival of the British species. The first decision which had to be made was which species to regard as British.

It was decided that priority must be given to the twelve truly native species, these being the Adder Vipera b. berus, the Grass Snake Natrix natrix Helvetica, the Smooth Snake Coronella a. austriaca, the Viviparous Lizard Lacerta vivipara, the Sand Lizard Lacerta a. agilis, the Slow-vvorm Anguis f . fragilis, the Common Frog Rana t. temporaria, the Common Toad Bufo b. bufo, the Natterjack Toad Bufo calamatia, the Crested Newt Triturus c. cristatus, the Smooth Newt Triturus v. vulgaris, and the Palmate Newt Triturus h. helveticus. Considering their total ranges in Europe and Asia as a whole, none of these species can be regarded as rare, but the British populations have been isolated from the Continental ones for at least some 7,000 years and have presumably undergone genetic Variation which must one day prove to be of considerable scientific interest. Two others—the Wall Lizard Lacerta m. muralia and the Marsh Frog Rana esculenta ridibunda— have also been included with lower priority, since although they are introduced species, both have long-standing, viable, selfsupporting colonies in favourable areas, and there is no obvious reason why they should not continue to maintain themselves in these areas provided the habitat is not adversely altered. The Position with regard to the Edible Frog Rana e. esculenta is more obscure. At one time common in some areas, it is now limited to a few small localities, in some of which at least it is a recent introduction, and information is required to decide whether these populations may be regarded as viable. Other introduced species, such as the Midwife Toad Alytes o. obstetricans, the European TreeFrog Hyla a. arborea, Ewing's Tree-Frog Hyla ewingi, and the

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Alpine Newt Triturus a. alpestris are all either extremely local recent introductions or live under more or less artificial conditions, and therefore cannot be considered at this stage as valid members of the British fauna.

Following its initial studies, the Committee decided that three species—the Smooth Snake, the Sand Lizard, and the Natterjack Toad—are in real danger of extinction unless active measures of conservation are carried out. On a long-term basis, it would seem necessary to set up reserves where the habitat for these species can be preserved and if necessary improved. In Cooperation with local authorities and organisations, several areas have been selected where suitable measures are being put into effect for both the Smooth Snake and the Sand Lizard, but work on the Natterjack Toad is still basically in the research stage.

The Committee decided that its own proper function must be to act as advisors to l o c a l conservation bodies, rather than endeavour to carry out its own projects in isolation. There are many reasons for this, but the main one is that, particularly in a country such as this where conflicting pressures on land use are always increasing, habitat control must take into account the needs of many species and not be limited to those of one or two.

The Committee has therefore taken up contact with a number of local bodies such as County Naturalist Societies and is, as it were, offering its services as specialist advisors in respect of reptiles and amphibians. In return, it is receiving a lot of valuable help from members of such bodies in setting up the necessary S t a t i s t i c a l records covering distribution and population trends, and in obtaining straightforward zoological information on the requirements of different species.

In brief, therefore, the Committee is making an immediate proposal to County Naturalist Societies. If any of your members are particularly interested in herpetology and able to carry out O b s e r v a t i o n on a particular area, we would welcome t h e i r C o operation and would brief them on our particular requirements.

Of the above mentioned three species which are considered to be in danger only one, the Natterjack Toad, is found in Suffolk and we are anxious to obtain up-to-date information on its distribution in the County. A major factor in bringing about the decrease in numbers of some species over recent years has undoubtedly been over-collecting. We therefore make a point of not publishing information in a form which would reveal precise localities where rare species might be found. We badly need more information on populations in many areas, but there would be no point in collecting this information if it merely resulted in further collection of species we are trying to conserve. In the case of the Natterjack it is not necessary to collect any specimens to take home for

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identification: it can easily toad in the field by having back from the snout or back line develops in the tadpoles

be distinguished from the common a yellow stripe extending down the of the head to the vent. The yellow at the time when the forelegs appear.

In Suffolk it has only been recorded along the coast and members who live in that area could do useful work by looking for it. The breeding season is mainly in April, May, and June when the eggs are laid in shallow water, even in small puddles or ditches only an inch or two in depth: it has even been recorded from brackish water.

Mr. J. Longe of Huntingfield Old Rectory, Haiesworth, has consented to act as Recorder for the County and as a link between local naturalists and the Herpetological Society: all records should be sent to him.

Excellent descriptions of all the British species of reptile and amphibian, as well as useful information on habits and ecology, are given in " T h e British Amphibians and Reptiles" by Malcolm Smith (first published by Collins in the New Naturalist series in 1951, with a revised edition in 1954).

J. W. Steward, Chairman, Conservation Committee, British Herpetological Society, 77 Churchill Road, St. Albans, Herts.