Berkshire Network for Invertebrate Conservation

Newsletter no. 3 – July 2000

Welcome to a rather brief third BNIC newsletter. The first thing to note is that we have two field meetings coming up soon - see details below. Apologies for not providing more advance notice about these, but all BNIC members are welcome to attend, and thanks to Malcolm Storey for organising them. Matt Smith reports on Berkshire stag beetle records, and there are updates on other local news. As usual I will be writing to you at the end of the summer with details of our autumn meeting, so please continue to pass on any news items or articles that can be circulated or put into the next newsletter. Thanks again to the Greenham Common Trust for funding our mailing costs.

Martin Harvey

Stag beetles in Berkshire

During 1998, the People’s Trust for Endangered Species (PTES) organised a national survey of the stag beetle Lucanus cervus. So far, PTES have been sent over 11,000 records of stag beetle sightings, mostly from the 1998 season. In total, over 70% of the surveys records came from urban areas. The stag beetles’ stronghold remains the South East of England, with a few small populations in parts of South Wales, the South West of England and areas of Worcestershire.

PTES received over 660 records for Berkshire. The resulting distribution map (below) shows the stag beetle to be confined almost entirely to the central and eastern parts of Berkshire. There are good numbers of records from areas such as Reading, Wokingham, Bracknell and Maidenhead, but none from towns such as Newbury or Hungerford. Why this should be the case is unclear. PTES are still collecting stag beetle records, and would be particularly interested in any from the west Berkshire area. Records can be sent to PTES, or via Matt Smith or Martin Harvey.

Rosemary beetles in Berkshire

The rosemary beetle Chrysolina americana is a fairly recent addition to our beetle fauna. It is originally from the Mediterranean region, the adults and larvae feed on rosemary, lavender and possibly other labiates such as thyme. It was first recorded from the UK in 1963, when a number of individuals were found in a house in Cheshire. The next record was from the RHS Garden at Wisley in 1994, when a few beetles were found on potted rosemary plants. Since then, the species has been recorded from lavender plants outside the Shell Building, Waterloo, from outside the Tate Gallery (on lavender), from Weybridge (Surrey) and from rosemary bushes outside the BENHS building at Dinton Pastures, Hurst. My own garden in Winnersh (just over a mile away from Dinton Pastures) has held a small colony of these beetles since at least 1998. I have found adult beetles on lavender, rosemary and thyme plants. Though I have not seen any larvae in my garden, I found teneral adults last August and several pairs of beetles were seen in cop, suggesting that this is a breeding colony. The beetle overwinters as an adult and aestivates during the hottest part of the summer.

Adult C.americana are very easy to identify. They have a typical rounded ‘leaf-beetle’shape and are 6-8mm long, iridescent dark green with dark red longitudinal stripes on the elytra. Adult beetles appear to be fairly immobile during the day, spending most of their time tucked in between the florets of lavender flowers or at the base of the whorls of rosemary leaves. A late summer inspection of lavender flowers or rosemary bushes may well produce more records of this attractive beetle, particularly if looked for in the western parts of the county. I would be interested to receive any details of further discoveries of this beetle in order to keep track of its spread.

Matthew Smith, 24 Allnatt Avenue, Winnersh, Berkshire.

Email: MatSmith1@compuserve.com; tel: 0118 979 4313.

BNIC survey at Windsor Great Park

BNIC members are continuing to record invertebrates at Windsor, especially in the Bear’s Rails wood-pasture restoration area. David White, David Fuller and Des Sussex had a memorable evening on 28 June, when they recorded two male specimens of the Red Data Book 1 cranefly Ctenophora ornata as well as two Biodiversity Action Plan moth species. As reported in previous BNIC newsletters, the spectacular C. ornata is known only from Windsor and the New Forest, and we believe this is the first time it has been found in the northern part of the Park. The moths were the festoon and the heart moth. The latter species is a particularly high priority as it has very few confirmed breeding sites, the best-known being in Surrey. George Tordoff and colleagues have also recorded it further south at Silwood Park in 1999 and 2000, so there is encouraging evidence of a strong population around Windsor.

Moth recording at Bear’s Rails this year has also produced good numbers of great oak beauty, in Berkshire known only from Windsor at present, as well as non-moth species such as the Red Data Book 3 narrow timber beetle Colydium elongatum, found on an ancient tree trunk by Martin Harvey during an earlier mothing evening.

New report on dragonflies of Bracknell

An excellent report by John Ward-Smith and Des Sussex summarises the status of all 28 species of dragonfly and damselfly known from Bracknell Forest Borough, and provides distribution maps. Twenty-three species are resident in the Borough, including four that are nationally rare: small red damselfly, downy emerald, brilliant emerald and keeled skimmer. The report covers the years 1995–1999. The main dragonfly sites in Bracknell are listed, and a review of conservation measures in the District concludes that dragonflies have benefited, but continuing effort is needed to maintain suitable habitats for them.

Further details from: John Ward-Smith, 11 The Ridgeway, Bracknell, Berkshire, RG12 9QU.

Meeting report: Braywick and Windsor, 2 April 2000

BNIC’s spring meeting was once again held at the Braywick Nature Centre. Some pleasant spring weather allowed us to spend some time recording in the Centre’s grounds, where we discussed the problems of maintaining dead wood habitats in a site open to public access, along with all the health and safety fears that this entails. A standing dead tree trunk at the edge of the main grass area was found to be home to the Nationally Scarce ant Lasius brunneus, and further in the grounds exit holes of the Nationally Scarce jewel beetle Agrilus sinuatus were found in hawthorn branches. The Lasius brunneus tree has subsequently had to be ‘made safe’, but BNIC recommended that any parts of the tree that were being removed should be re-positioned elsewhere in the grounds, so that the habitat can continue being used.

In the afternoon we moved on to Windsor Great Park and found a mixture of spring-flying insects, such as the longhorn micro-moth Adela cuprella (recently confirmed in Berkshire for the first time by Ian Sims and now turning up in several places) and over-wintering insects in tree hollows and trunks, including a queen hornet Vespa crabro still hibernating in a crevice in a decaying tree trunk.