Observations of the Small Copper butterfly at Tangham, Autumn 1994

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Suffolk Natural History, Vol. 31

OBSERVATIONS OF THE SMALL COPPER BUTTERFLY AT TANGHAM, AUTUMN 1994 RICHARD G. STEWART The Forestry Commission area at Tangham, east of Woodbridge, has a series of habitats, including coniferous plantations, deciduous woodland, grassland, scrub, heathland and the peat-filled fen wetland along the Tang Valley. Ponds have been developed along the river Tang, three of these forming part of the 'Phoenix Trail'. * The area has a good ränge of butterfly species, including colonies of white admiral, speckled wood and grayling; 23 species have been recorded since 1993. On previous Autumn visits I recorded individual specimens of the small copper, Lycaena phlaeas. Although this species does not overwinter in adult form it is often late-flying. Beaufoy (1947), remarks 'The small copper is triple brooded, and emergence from the chrysalis takes place, usually, in the months of May, July and September . . . in a very warm late summer there may even be a partial fourth generation in October, whose eggs hatch before the onset of winter'.

My visit on September 18th 1994 largely followed the füll length of the Phoenix Trail, with diversions to explore the rider beyond the two Are ponds and the bridge pond. Initially, small coppers were observed on ragwort, Senecio jacobaea, with a maximum of eight butterflies on one plant. The clumps of bell heather, Erica cinerea, were another nectar source, being particularly abundant along the rides above the three ponds. A final detour was made to explore the füll length of the eastern edge of the plantation of Corsican pines due East of the Tang Valley. This strip of rough grassland, approximately 30 ft in width, contained flowering hawkweed, genus Hieracium, wild chamomile, Chamomilla recutita, and ragwort. These nectar sources, in a sunlit position during my recording, accounted for 56 small copper sightings, just over 50% of the total of 111 recorded. Of these 32 were in flight or on the ground (referred to in future counts as FG), and the remaining 79 were on the following nectar sources: ragwort (27), bell heather (16), wild chamomile (17), hawkweed (14), creeping thistle, Cirsium arvense, (4) and blackberry, (1).

The second visit, on September 22nd, was also in sunny conditions, but with stronger wind. The same route was recorded but the rides above the three ponds were followed onto the wider forest track until the areas of bell heather ended.

This undoubtedly accounted for the increased total of small coppers recorded (370), 210 being on bell heather. The other nectar sources recorded were ragwort (26), hawkweed (23), wild chamomile (20), yarrow, Achillea millefolium, (6), creeping thistle (5), gorse, (1) and soapwort, Saponaria officinalis, { 1). FG accounted for 78.

The third visit was on September 25th. My wife and I searched the same areas in as much detail as the three hours at our disposal permitted. Again the weather was sunny and we counted a total of 433 small coppers, including some along the rides east of the woodlark conservation area. Subtracting the 193 FG, the remaining 240 were observed on the following plants: bell heather (170), ragwort (22), wild chamomile (15), hawkweed (12), yarrow (10), creeping thistle (6), blackberry flowers (4) and soapwort (1). The butterfly went

Trans. Suffolk Nat. Soc. 31 (1995)

SMALL COPPER AT TANGHAM

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directly from this soap wort to white campion Silene alba.

Only ten small coppers were observed on yarrow, but this plant was not abundant Six small coppers were feeding on two sunlit flowers and a subsequent conversation with Rob Macklin, the RSPB Warden at North Warren, revealed that late-flying small coppers there were using yarrow as their main nectar source.

The three Visits were restricted in time and consequently although courtship behaviour was noted it was not observed in detail. No attempt was made to monitor the prevalence of the small copper's food plants, common sorrel, Rumex acetosa, sheep's sorrel R.acetosella, and docks, Rumex. On the third visit my wife observed several of the aberrant form caeruleopunctata, which has a series of blue spots along the bottom edge of each hindwing.

These numbers far exceed my previous observations of this butterfly and any similar records from other County sites will be welcomed for comparison.

Other butterflies were relatively scarce at the site. Those recorded dunng the three Visits were: small white (2), red admiral (2), grayling (2), common blue (3) and Single sightings of small tortoiseshell, comma and speckled wood.

By the time of the next visit, November 4th, the combination of muchreduced nectar sources and restricted sunshine which was soon eclipsed by cloudy and cold conditions, produced a count of just five small coppers, four on the remaining flowers of bell heather and a tattered fifth specimen clinging to ragwort. Mainly as a consequence of reports by Wilfrid George of small copper sightings in November from the Aldeburgh area and along the Sailor's Path, I made a final visit to Tangham on November 16th. By concentrating on the few flowers of bell heather still surviving I eventually located one small copper butterfly, clinging to a flower. It was comatose but stirred feebly when gently stroked.

These November sightings are exceptional and coincide with the fact that the first half of November was the wärmest since records began in 1659. Again late records of the small copper would be welcome and other observations of its presence at Tankham in previous years. Finally, I thank Richard Davis, Environment Forester at Tangham for his help during this study.

References Simpson, F. W. (1982). Simpsons Flora of Suffolk. Suffolk Naturalists' Society, Ipswich.

Beaufoy, S. (1947). Butterfly lives. Collins, London.

Thomas, J. & Lewington, R. (1991). The butterflies of Britain and Ireland.

Dorling Kindersley, London.

(

Richard G. Stewart, 63 Belstead Road, Ipswich IP2 8BD

Trans. Suffolk Nat. Soc. 31 (1995)

Plate 7: Phoenix Trail, an area of mixed habitats in the forest at Tangham, east of Woodbridge. (p. 16).

£ Plate 8: Small Copper, Lycaena phlaeas L„ one of the butterflies found along the Phoenix Trail. (p. 16).