NCC Received 25/07/2017
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Invertebrate Survey of site at Barton-in-Fabis Nottinghamshire undertaken by Richard Wright NCC Received 25/07/2017 on behalf of PleydellSmithyman Limited September 2015 Contents 1 Introduction 2 2. Habitats 2 3 Methods 2 4 Results 3 5 Discussion 6 6 Recommendations 6 7. References 7 Appendix 1 Complete list of species recorded 8 Appendix 2 Site plans 16 Received Appendix 3 Site habitat photographs 18 NCC 25/07/2017 1 1. Introduction The survey was carried out by Richard Wright, an experienced self-employed specialist invertebrate surveyor. An assessment was first made of the habitats present and the potential of the site for invertebrates. A survey was then carried out using methods considered most appropriate for the likely invertebrate assemblages. The specimens were identified and the results examined using Natural England's ISIS application to determine actual assemblages present. The species list was examined for any species deemed to be of conservation concern, i.e. those included in national or local BAPs, or designated as nationally scarce. Recommendations are made in this report for maintenance of the invertebrate interest of the site. 2. Habitats On the first visit the habitats present on the site and their potential invertebrate interest were assessed using the Phase 1 habitat survey map supplied. The major habitats present were : arable farmland with some uncultivated margins improved grassland semi-improved flowery grassland marshy grassland Received hedgerows small areas of broad-leaved woodland small areas of scrub NCC 25/07/2017 tall ruderal herbs a large pool, a small pond and a ditch From these habitats it was considered that the semi-improved and marshy grassland, together with wetter areas along the ditch and pool margins, were most likely to be of particular interest for invertebrates. While all habitats were surveyed, particular emphasis was placed on these. 3. Methods The site was visited on three occasions, 15th May, 12th June and 7th August, 2015. Weather conditions on each visit were dry, warm and suitable for survey. On the first and last visits, the whole site was walked and surveyed using a sweep net and beating tray. On the second visit, attention was confined to a representative sample of what were considered to be the most significant habitats as noted in 2. above. Fifty pitfall traps, ten lines each of five traps, were set on the first visit and emptied and removed on the second. Two lines of traps were set in the Barton Flash area, area 2 on Fig 2 in Appendix 2, the remainder 2 in area 1 on the same plan. In area 1, four lines were set in the semi-improved grassland, three lines in the marshy grassland and one line along the edge of the ditch. These were considered the habitats most likely to include invertebrate assemblages of interest. Each pitfall trap consisted of a clear plastic cup of top diameter 9 cms, sunk in the ground until the lip was flush with the ground surface, and filled with saturated salt solution as a preservative.. Pitfall traps are primarily of value in recording ground-running species, particularly beetles and spiders. The two pools were sampled on the last visit. However, both were difficult to acess with Pond 1 being largely surrounded by overhanging scrub and Pond 2 by extensive wet silty ground. Constraints There were no specific constraints on the survey. The survey covered the peak periods for a wide range of species and the sample is considered easily large enough to make a good assessment. 4. Results The total number of species recorded was 365. These were distributed as follows : Coleoptera (beetles) 174 Diptera (flies) 67 Hymenoptera – Aculeata (bees, wasps & ants) 11 Arachnida (spiders & harvestmen) 41 Hemiptera (true bugs & leafhoppers) 34 Received Lepidoptera (butterflies & moths) 11 Others 27 NCC 25/07/2017 The particularly large percentage of beetles is mainly because these were the dominant group in the pitfall traps. This number of species is considered more than adequate for a robust site assessment to be made. Analysis using ISIS ISIS is an Excel based application developed by Natural England to identify invertebrate assemblage types and scores each assemblage type according to its conservation value. ISIS is based on a definition of an assemblage as a suite of species occurring in the same piece of homogenous habitat. Two levels of assemblage type are recognised by ISIS: Broad Assemblage Types (BATs): These are characterised by species that are more widespread; Specific Assemblage Types (SATs): These are characterised by stenotopic species that are habitat specialists and considered to have intrinsic conservation value and are generally found on sites with conservation interest. SATs are more narrowly defined in terms of habitat type than BATs and each SAT is nested within a parent BAT. Assemblage types are linked to species by a coding system that carries information on the closeness 3 of their relationship. BATs are identified by a two digit code and SATs by a four digit code. It should be noted that not all invertebrate groups are included in the ISIS analysis. An assessment of the value of the invertebrate assemblages present within a site is then undertaken using the results generated and the species information provided by ISIS. The species list from the site was fed into ISIS and the results follow. The site was not considered to be in Favourable condition for any SAT or BAT. Very few species were noted as being associated with any SAT, reflecting the relative lack of the associated habitats on the site. SATs are therefore not considered further. By far the largest number of species (166) was allocated to BAT F2 grassland and scrub matrix. These are generally common species found widely in the general countryside in areas such as road verges, hedgerows and open woodland. They therefore have comparatively little value in site assessment. 41 species in total were allocated to wetland BATs, these being species which were found in the marshy grassland, in Barton Flash, around the pond margins and along the ditch. 27 species were allocated to BAT F1 unshaded early successional mosaic, these being species mainly recorded from the arable field margins. Species of conservation concern Species considered of conservation concern are those designated as Red Data Book or nationally scarce and also those included in national or local Biodiversity Action Plans (BAPs). Received Six species, all beetles, are presently designated as nationally scarce, one of which is also included in the UK BAP. NCC 25/07/2017 Necklace Ground Beetle Carabus monilis (Carabidae) Biodiversity Action Plan UK list of priority species: Priority Species Present status “Nationally Notable “B”. Proposed revised status : Endangered A review of the statuses of British ground beetles is presently being undertaken by Dr. M.G.Telfer, organiser of the national recording scheme. In correspondence with the author of the present report, Dr. Telfer has indicated that he is proposing to change the status under the new IUCN guidelines to Endangered. This is a considerable elevation and is based on the fact that this large ground beetle has apparently undergone a greater decline than any other species, both in Britain and some other European countries. The habitat requirements of the species are not clear. Arable field margins are often quoted, but in the present author’s experience it is most often found in ungrazed and unmown grassland, particularly adjacent to hedgerows and woodland. There is some evidence that it is especially susceptible to the effects of pesticides and is therefore often found on less intensively managed ground. It is an annual species, with 4 adults mainly in summer. As far as the author has been able to determine from the NBN Gateway, all records for Nottinghamshire appear to be old, mainly from the 1920s, although this should be checked with the local Biological Records Centre. Sixteen specimens were found on the survey, all from pitfall traps in the semi-improved grassland shown in area 3 on Fig 3 in Appendix 2. It should be noted that : only a small part of the site could be surveyed with traps there is a large area of similar habitat on the site which suggests that there could potentially be a very large population of this beetle on the site. It should be noted that no specimens were found in the marshy grassland where the similar Carabus granulatus, a typical species of wetland habitats, was abundant. It therefore appears that C. monilis is confined to the unimproved grassland. Chlaenius nigricornis (Carabidae) Given Nationally Notable “B” status by Hyman & Parsons (1992) but this species is now known to be widespread and not uncommon over a large part of England and Wales with 725 records on the NBN Gateway. Very likely to lose its status in the review presently in progress. Associated with a wide variety of wetland habitats. A single specimen was found in a pitfall trap along the edge of the ditch in area 4 on Fig 3 in Appendix 2 Tillus elongatus (Cleridae) Received Given Nationally Notable “B” status by Hyman & Parsons (1992) revised to Scarce by Alexander (2014). Mainly in England south of the Humber. A predator of larvae of other beetles on old broad-leaved trees, and usually in hard dead heartwood. TheNCC 25/07/2017 larvae hunt nocturnally under bark and on the outside of the tree. A single specimen was swept from hogweed Heracleum sphondylium flowers near the river bank at point 1 on Fig 3 in Appendix 2. Possibly associated with old willows along the river bank. Microplontus campestris (Curculionidae) Given Nationally Notable “B” status by Hyman & Parsons (1992). A weevil associated with oxeye daisy Leucanthemum vulgare.