A selection of some of the key items of interest from 2009 are described below.
Advice and help:
has been given to many individuals and organisations including specimen identification, and advice on conservation and habitat management. Specific examples include:
(a) Management advice was given to the Gloucestershire FWAG on the conservation of Helicella itala (figure 1) living on Cleeve Common, near Cheltenham.
(b) Guidance and literature was sent to the London Wildlife Trust on management plans for Isleworth Ait Nature Reserve (an island in the River Thames near Kew) with regard to important populations of Pseudotrichia rubiginosa and Alinda biplicata.
(c) Advice was supplied to ‘Environ’ on possible risks of a housing development near Debden in Suffolk, to populations of Vertigo angustior living close by at Martlesham Creek.
(d) Argyll and Bute Council were provided with molluscan suggestions to include in their Local Biodiversity Action Plan (LBAP). Three candidate species Vertigo geyeri, Margaritifera margaritifera and Atrina fragilis were proposed (all three species are UK BAP priorities and the latter two also receive protection under the Wildlife & Countryside Act, 1981). The only known populations of V. geyeri in Western Scotland live on Islay (figure 2) and there are many rivers in this region supporting healthy populations of M. margaritifera. There is also good reason to believe that several, only partially studied, river-catchments in the area are likely to reveal further populations of this mussel. The fan mussel A. fragilis (figure 3) has been recoded at various locations off the Argyll coastline (e.g the Loch Sween area), but is threatened (as are many other marine molluscs) by beam trawling and scallop dredging in the area.
(e) The Sussex Wildlife Trust was given assistance in the interpretation of an environmental impact assessment (produced by a consultancy company) relating to water level restoration plans for Chingford and Burton Mill Ponds LNR, Petworth. Fens around these ponds support many invertebrates of national conservation importance including the largest (and possibly only remaining viable) Vertigo moulinsiana population in Sussex (figure 4).
(f) Information was provided to ecologists working to avoid negative impacts on populations of Helix pomatia understood to be present living on embankments threatened by widening schemes on the M25 motorway.
(g) Information was given to the UK Hedgerow Habitat Action Plan Steering Group on rare and BAP priority molluscs potentially associated with hedgerows (for more information visit www.hedgelink.org.uk ).
(h) Natural England were provided with information relating to recent worrying reports of molluscan declines and losses (e.g. Helicella itala. Monacha cartusiana) at several key chalk grassland SSSI and other sites throughout the Sussex Downs. In most cases problems relate to habitat neglect or possible mismanagement.
(i) In June 2009 MJW attended a meeting at Amberley Wild Brooks organised by the Sussex Biodiversity Partnership who own grazing marshland on part of the Brooks. The meeting, which was attended by local landowners, farmers, and representatives of the RSPB, Natural England and the Sussex Wildlife Trust (figure 5), was initiated to discuss ditch management strategies to maintain overall biodiversity and to retain such endangered molluscs as Anisus vorticulus, which lives in some ditches in this area.
The production of molluscan wildlife reports continued in 2009 with the inclusion of entries in February, June and October. Perhaps the ‘star’ item of the year came with the reported discovery of the ghost slug Selenochlamys ysbryda at a number of sites in and around Cardiff. This new species to science, is thought to have been introduced to the UK from the Caucasus.
Other key items included news of (1) Caecum armoricum discoveries in Sussex, (2) Marstoniopsis insubrica living in Norfolk, (3) a considerable range extension of Pseudanodonta complanata in the River Wye and also many new records of the mussel in the Llangollen Canal (4) the surprising new vice-county record of Pisidium tenuilineatum for Cambridgeshire and (5) the discovery, in the Brecon Beacons, of the most southerly known population of Vertigo geyeri in the UK. In addition to the item on Caecum, marine entries were rather dominated by ‘sea slug’ items. These included the increased number of new sea hare Aplysia punctata records from the south coast (possibly linked to climate change) as well as new discoveries of Doris ocelligera, Trapania tantanella and Discodoris rosi. Finally an attempt was made to publicise the ambitious OU Cepaea ‘megalab’ initiative in good time for readers to make an individual contribution to this Darwin Year event.
Invertebrate Link and The Invertebrate Conservation Trust (Buglife):
Membership of Invertebrate Link and Buglife continues to provide useful contacts with members from other NGOs and governmental organisations (e.g. Natural England, Countryside Council for Wales, Royal Entomological Society) concerned with invertebrate conservation.
The UK Biodiversity Action Plan: Terrestrial Mollusc Steering Group (7th Meeting Worcester 15.10.2009)
This steering group reconvened after a five year gap, during which time much had happened on the UK BAP front. Those attending included three members of the Conchological Society (figure 6). Since the previous steering group meeting in 2005, the 2007 UK BAP review had reconfirmed all of the existing terrestrial BAP molluscs (Vertigo moulinsiana, V. geyeri, V. genesii, V. angustior, Quickella arenaria) as well as adding Vertigo modesta and Truncatellina cylindrica. The Group agreed that these two additional species should be added to its remit. The meeting started with a review of how each of the original terrestrial BAP species had been faring throughout the UK and Eire. The most significant news included:
(a) England: In Upper Teesdale the important populations of V. genesis had been monitored and appeared to be in good condition.
(b) Scotland: SNH had produced a leaflet advising landowners on the sympathetic management of V. geyeri sites on Islay, whilst a new V. angustior SAC had been announced by the Scottish Parliament for the recently discovered population on Garron Point, Aberdeenshire.
(c) Wales: News of newly discovered BAP molluscs included V. angustior from dunes and upper saltmarsh in the Pembrey area (Carmarthenshire); V. geyeri from the Breacon Beacons (at its most southerly known UK site) and V. moulinsiana in a fen in Radnorshire. CCW had initiated monitoring of V. geyeri at fens on Anglesey, whilst also embarking on the Anglesey and Llyn Fen LIFE project, which aims to improve a large area of fen including the three known sites for V. geyeri in N. Wales
(d) Northern Ireland: Monitoring of a number of V. geyeri and V. angustior populations had taken place.
(e) Eire: Evelyn Moorkens presented a PowerPoint summarising the situation regarding V. geyeri, V. angustior and V. moulinsiana in the Republic. Work was underway on these species at all SACs (Special Areas of Conservation) together with a similar number of non- SAC sites supporting these snails. It was reported that in Ireland, of these three Vertigo species, V. moulinsiana was faring the worst. Evelyn had also introduced an Access database to store a wide range of information on each species including links to a Vertigo GIS ‘layer’. Such a resource is an ideal to way allow the integration and reporting of various conservation interests in each SAC.
When the steering group was first established its primary purpose was to oversee national molluscan BAP targets, to identify areas of responsibility for the implementation of targets, to liaise with relevant Habitat Steering Groups and to coordinate reporting of annual BAP progress.
Since the group last met the administration of the BAP process has changed in a number of ways. Firstly BAP responsibilities are now devolved to home country level and secondly species conservation will mostly be achieved by county biotope (e.g. ‘coastal’ ‘upland’, ‘wetland’ etc) steering groups. These new changes therefore presume that, except in special circumstances, individual species steering groups are no longer needed. The Group felt, however, that as most of the species under our consideration are present in more than one broad habitat type (see table below), then our role is still important in:
(a) maintaining an overview of the conservation of each species so that country biotope groups can be advised of conservation actions;
(b) to consider research requirements;
(c) to contribute to country BAP & EC Directive reporting.
To assist in achieving an overview, the Group considered that the Access database developed for Eire by Evelyn (see above) was a particularly valuable tool. It was agreed that it would be wise in assisting the Steering group’s work if this database could be extended to include details of each of the seven UK BAP species throughout the rest of the British Isles. Evelyn will be working with Adrian to see if a joint project can start. With regard to the two new species V. modesta and T. cylindrica, no firm actions had yet been determined by the Group in relation to specific conservation action. In consideration of Quickella arenaria, Natural England would be monitoring populations at its two UK strongholds at Braunton Burrows in Devon and Sunbiggin Tarn in Cumbria. Evelyn highlighted that Quickella, which has no formal conservation status in Eire, is in overall decline there. The Group therefore agreed to support any moves to raise its conservation status in the country.
Updating Red Lists
Work on the 2008 revision of the Red Data lists was largely completed during the year; it is hoped that, following final consultations and a meeting of the Conservation and Recording Committee in early 2010, a submission will be made to JNCC.
Rare molluscs possibly threatened by proposed developments at St Aubin’s Harbour, Jersey
In November 2009 we learnt of plans to develop St Aubin’s Harbour in Jersey (figure 8) including infilling and waterproofing of the uncemented granite blocks of two Victorian piers. These plans, together with the news that freshly dead shells of the Looping Snail Truncatella subcylindrica and Paludinella littorina had been found associated with the pier structure, were brought to our attention by Paul Chambers, a local conchologist. Both Paul and Jan Light considered that the crevices between the blocks were very likely to support live Truncatella and Paludinella. Both of these small snails live in specialised upper-shore micro-habitats (such as rock crevices) and have a very localised distribution in the UK, each being restricted to very few sites, chiefly on the south coast.
In the UK, their conservation importance is recognised by both being placed on Category 3 (rare) of the British Red Data Books, with P. littorina also being given protection on Schedule 5 of the Wildlife and Countryside Act, 1981.
Unfortunately different conservation regulations apply in the Channel Islands and the controls of the Wildlife and Countryside Act do not apply there. Both of these species were later confirmed living at St Aubin’s, making the site of particular interest; there are currently only two other UK locations where these molluscs have been recorded living together (the Fleet lagoon in Dorset and on an abandoned pier at Archirondel on the east coast of Jersey). As a result of these possible threats, the Conchological Society and later Buglife sent letters to Jersey Parliament members for Economic Development, Planning and Environment, together with the Marine and Coastal projects officer. Reassuringly, before the end of the year, we received replies to our correspondence notifying us that when the EIA (environmental impact assessment) was submitted, checks would be made to ensure that population assessments of these snails had taken place. News of this molluscan dilemma reached the local press and on 9 th December 2009 the Jersey Evening Post ran an article titled “Save our molluscs” explaining the potential environmental damage that the repair work might cause. Perhaps the paper exaggerated matters slightly by explaining that both snails were ‘critically endangered’ and suggesting that they were amongst the rarest species of molluscs in Europe! It also mistakenly claimed that both species were included on the UK Biodiversity Action Plan (BAP). At the end of 2009 no decision had been made; we wait, and will report on developments in 2010.
Associations with other organisations:
The Conservation Officer continues to attend conservation committee meetings of The Sussex Wildlife Trust. In the ‘Adastra’ magazine for 2009, I reported on the rediscovery of Gyraulus laevis for the vice-county of West Sussex, raised concerns at the problems facing Vertigo moulinsiana in the county and drew attention to the reported decline on the Sussex Downs of chalk-grassland molluscs of conservation importance (Adastra 2009, Sussex Biodiversity Record Centre, Henfield, West Sussex).
|figure 1: Helicella itala on limestone grassland.
figure 2: Vertigo geyeri habitat: loch-side fen, The Oa, south Islay.
figure 3: Atrina fragilis
figure 4:!Vertigo moulinsiana habitat: Burton Mill Pond, Petworth, West Sussex.
figure 5: Ditch management meeting on Amberley Wild Brooks.
figure 6: The UK Terrestrial Steering Group Meeting, October 2009.
figure 8: St Aubin’s Harbour, Jersey. (photo: Nicolas Jouault)