ON THE STATUS OF PONDS AND GREAT CRESTED NEWT TRITURUS CRISTATUS IN SUFFOLK

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ON THE STATUS OF PONDS AND GREAT CRESTED NEWT TRITURUS CRISTATUS IN SUFFOLK TOM LANGTON, GEORGE MILLINS AND CATHERINE LANGTON Summary Suffolk pond numbers are re-evaluated, with the most recent (1999) estimate of over 22,635 ponds remaining found to be based upon data in which approaching 40% of pond grid reference locations appear to be erroneous.

Applying adjustments provides a revised estimate of 11,500 ponds in 2007 plus or minus 1000 ponds. However, the number of ponds that still hold water for 4–7 months per year (or ‘wet ponds’) is estimated at around 9240. Recent Suffolk Wildlife Trust surveys found that over 80% of all ponds had low water volume, were heavily silted and in a highly degraded state, but there is a possible slowing of pond loss rate since 1990. By relating the percentage occupancy of ponds by the European protected amphibian species Great crested newt Triturus cristatus to the probable ‘wet’ pond numbers for Suffolk, 1000 breeding ponds plus or minus 250 ponds are judged to remain.

The status of standing freshwater ponds and their aquatic wildlife in Suffolk is described as being in crisis, with little immediate prospect of significant funding to reverse the trend of continued decline. This is despite the clear and longstanding government obligations over 25 years to ensure conservation action is undertaken. Recommendations for action to conserve Suffolk ponds are given.

Introduction The English counties of Suffolk and Norfolk, together with Cheshire and parts of its adjoining counties are the parts of England and Wales with highest pond densities (Rackham, 1986). While the building of large numbers of garden ponds in recent decades has offered a widespread additional habitat for many plant and animal species, the older, and sometimes ancient, ponds that typify much of the British lowlands remain the vital standing water network. A core component of this wildlife asset are the ponds of the East Anglian Claylands, within which many of the Suffolk ponds and particularly the South Norfolk and High Suffolk Claylands Character Area pond supercluster (sensu: Grayson, 1993) are located.

Defining and categorising small water bodies from a historic and nature conservation perspective has proved difficult (Rackham, op. cit.). A working definition for ponds, used by the group Pond Action in the early 1990s was ‘water bodies between 1 square metre and two hectares surface area that hold water for up to four months per year’ (see Wood et al., 2003). While this categorisation includes most garden ponds, it does not include the smallest pre-cast, plastic-lined ponds or old porcelain sinks sunk in the ground, so absolute definitions are clearly difficult. The Lowland Ponds Survey (Williams et al., 1996) defined ponds for that study as those between 25 m2 and 2·0 ha surface area and holding water for at least four months of the year.

Ordnance Survey maps do not include small modern garden ponds, built mainly with artificial liners over the last 40 or so years. Garden ponds have become increasingly numerous, especially in conurbations and there may be two million of them in the UK (Froglife, 1999). Many thousands of these are

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now established in Suffolk, mainly concentrated in larger towns, but also spread out in village and farm gardens. Ponds that are smaller than five metres in span, are likely to be relatively shallow. Without artificial liners they tend to dry out unless they receive a constant water supply from their catchment area throughout the year. A few exceptions exist for ponds in places such as forestry plantations, industrial sites and old airfields where they may be deep and steep sided to store water for fire fighting or to take storm water. The high surface area to volume ratio of smaller ponds means that evaporation dries them out more frequently than the relatively stable and slower-fluctuating water levels of larger ponds. Temporary pools on water meadows and fens also dry out due to variation in soil water retention and water table levels.

However, permanent ponds and ponds holding water between winter and late summer (usually 4–7 months or more) represent the greatest proportion of the permanent or semi-permanent freshwater pond volume, These permanent ponds provide habitat which is of the greatest direct importance for the majority of fish and amphibians, a large variety of aquatic invertebrates and many bird, mammal, and reptile species. These groups use ponds for breeding, as shelter and/or feeding habitat and they are equally valuable for many aquatic plants.

The fate of naturally formed ponds and the bulk of those built by humans, largely between the 16th–19th centuries is of increasing concern to nature conservationists and landscape historians. A fundamental starting point to their conservation is the accurate assessment of their numbers, distribution and density. Estimates of GCN populations have tended to be calculated by using the frequency of occupation percentage from a surveyed sample area, and extrapolating it to a whole region by multiplication with the number of ponds present for that region. An accurate assessment of pond numbers is clearly important for such purposes.

There have been two published reports that include estimated pond numbers for Suffolk. The first was based on work carried out by the Suffolk Wildlife Trust (SWT, 1990 a–c). The SWT study used 1:10,000 scale Ordnance Survey maps and ground verification of sample areas by fieldworkers to estimate numbers of mapped ponds and their actual numbers in the field. As a part of that study, GCN presence/likely absence was checked for surveyed ponds, using egg search and night time torch counting of adults at the pond edge. The surveys were carried out during the breeding season to give greatest opportunity to detect pond occupation by newts. The Suffolk Wildlife Trust estimated GCN population numbers in 1990 and 2005, but from relatively small samples. A second pond number estimate was carried out by English Nature (Sibbett, 1999), using data supplied from the Ordnance Survey records office. Further details of the surveys are as follows: SWT survey (SWT 1990) This study (referred to as the ‘SWT study’), was carried out in the late 1980s.

The entire 1:10,000 scale Ordnance Survey (O.S.) maps for Suffolk were reviewed by the SWT Manpower Services survey team to count the number of ponds. ‘Mapped pond’ numbers were determined sheet by sheet, employing

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Figure 1. A change in clay colour shows the former location of a great crested newt breeding pond, identified by a Suffolk Wildlife Trust survey but in-filled around in the late 1990s in Peasenhall. over 125 days of research time. The OS maps used were of 1920s origin with updates between1950 and1979. These maps were known to not necessarily reflect exact pond numbers at the time (late 1980s) and were considered a likely over-estimate of ponds present. This is because the cartographic removal of in-filled ponds is not always carried out, ponds infilled or drained many years ago are sometimes still shown. The scale of the maps allows identification of some tiny water features such as wells and is generally used in the production of 1:25,000 scale maps. The SWT survey did include mapped moats, counting them as one pond unless clearly fragmented into separate water bodies. The study provided an initial estimate of 15,400 mapped ponds for Suffolk, with a downwards adjustment for pond loss. The approach used is comparable with many other baseline pond surveys of this type for nature conservation purposes e.g. Greater London (Langton, 1985), Greater Manchester County (Grayson, Parker & Mullaney, 1991), Herefordshire (Brian & Harding, 1996) and Cheshire (Boothby & Hull, 1997).

To get an estimate of pond loss and the likely remaining pond numbers, three survey areas were evaluated by SWT by comparing mapped ponds with those present on the ground. In the three areas combined, 29 out of 111 ponds visited (26%) were no longer present although it was considered that the

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Ipswich area survey was untypical with a higher pond loss rate of 43% due to intensive house building. Applying a Suffolk-wide ‘minimum’ pond loss rate of 20% to the SWT map counts of the late 1980s, the estimate of remaining ponds for Suffolk reduces to 12,320 ponds in the year 1989.

English Nature Report (Sibbett, 1999) This study (referred to as the ‘EN study’) used electronic data supplied by Ordnance Survey from their main database. The method used was to request a list of the number of times the word ‘pond’ appeared and its grid reference, together with its Parish of origin. In the study this list was considered a good, but not exact, representation of the extent of rural ponds in Suffolk. The report estimated that Suffolk contained 22,635 ponds in 1999, treating each data point given by O.S. as a separate pond. This count did not include water bodies annotated with the word ‘moat’ or ’ditch’.

At the time of the drafting of the EN study report, the big difference between its findings and those of of the previous SWT survey was notable.

The present authors, prompted by their own knowledge of continued pond infilling and neglect, have investigated the reasons for the different estimates and the likely current trends in pond and GCN numbers in order to assess the immediate needs to prevent further losses.

Re-appraisal of the 1999 study Ordnance Survey data.

The O.S. data used for the EN study was obtained. OS grid references for the word ‘pond’ supplied were examined at a number of locations in Suffolk familiar to the authors. Samples from the EN study of tetrads (2 × 2 km) were selected to represent a range of pond densities and geographic locations (n = 16) across East Suffolk. The tetrads examined were: Pakefield TM58J, Sotterley east TM48S, Sotterley west TM48M, Shadingfield TM48H, Redisham TM48C, South Bramfield TM37V, Minsmere TM46T, Yoxford TM46E, Tunstall TM35M, Monewden TM25J, Brandeston TM26K, Monk Soham TM26H, Saxtead TM26M, Dennington TM26T, Dennington TM26Y and Dallinghoo TM25S. Within these tetrads, the ponds shown on the current (1999 revisions) O.S.1:25,000 scale maps were identified and counted. The same tetrads were examined on colour aerial photographic/satellite imagery to examine the relationship between the number of ‘ponds’ on the OS file used by EN, the number of ponds marked on OS maps and the numbers seen on the aerial images. Aerial images used were those shown on the online 2007 Google Maps website, representing photographs/aerial images from the later years of 1990s. The web site has a zoom facility to enlarge the ground images onscreen to a high magnitude for close inspection of land features at great detail.

A number of adjustments were made due to limitations of this method.

Ponds that were not clearly visible under tree aggregations and closed woodland were considered still to be present. This leads to an over-estimate of pond numbers, but it is the same method as that used by Ordnance Survey when updating without ground verification (Roberts, pers. comm.). Both the ponds that are clearly no longer present (lost ponds) and newly formed ponds within each tetrad were noted, as were the positions of places reported to be

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Figure 2. Remaining fragment of Great crested newt pond in Yoxford parish that has been gradually infilled with rubbish and spoil over previous decades. marked ‘pond’ with a grid reference identification number, that were away from trees but not visible on the O.S. maps or on the aerial images. A small number of field checks were made to attempt to locate features listed as ‘ponds’ in the O.S. database that were not identifiable as such on aerial images.

The 16 tetrad (64 km2) samples examined were found to hold approximately 920 of the O.S. ‘pond’ location grid references used in the EN study. Of these, 644 (70%) were found to be represented on the current (1999) map revision of the1:25,000 scale maps. Using aerial images from the late 1990s, of the 644 mapped ponds, 70 ponds (11%) were unambiguously no longer present, these being mostly ponds lost within arable farmland. The total mapped ponds remaining within the tetrads in 1999 was a maximum of 574, representing 62% of the 920 ‘pond’ locations originally listed by the EN study. This is referred to as a maximum because all woodland ponds were considered still present. Variation was considerable, with ponds located on aerial images present at between 35% and 88% (median 58%) of grid references supplied to the EN study.

Out of O.S. database listed positions for the word ’pond’ 276 (30%) could not be ascribed to a pond by 1:25,000 scale maps or aerial imagery. On close scrutiny of the 10 figure reference points, two types of location were revealed

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that suggested multiple occurrence of the word ‘pond’ for the same water body. These were places where two or more similar grid references were given for a single pond and those where multiple (up to six) grid references were given for ponds (often the larger water-bodies) crossing O.S. 1 km grid lines.

Other categories for locations found to be unoccupied by ponds included some in the middle of cropped land which could be old ponds not mapped in recent years and locations placed along, or at the corners of, field or woodland drainage ditches.

‘Pond’ O. S. grid reference checks in Parish samples All of the O.S. grid references for the word ‘pond’ within three Suffolk parishes; Bramfield, Great Cornard and Great Waldingfield were examined against aerial images and O.S. maps with selected site inspections to determine how well the data reflected the current situation on the ground. Grid reference locations from the EN study were checked on the aerial images.

Some ’lost’ ponds still appeared as slight variations in crop surfaces indicating where they once stood. Several locations were dry points along ditches, sometimes low points where water may once have collected, and where, for example, the ditch had been blocked or where ditches met at a boundary corner. In one woodland ditch examined, despite heavy infilling with twigs and leaves, water staining showed that at least at some point in the year water stood in the ditch corner for a period of time, possibly several months.

Of a total of 199 grid references for the word ‘pond’ in the three parishes, 138 ponds were located as definite or possible ponds, some 69% of the referenced ponds. The 31 % of ‘missing’ O.S. ‘pond’ locations were of five types. Most were duplicate locations; one or more grid references for a confirmed pond, the references being within a few tens of metres of each other. A smaller numbers of points were for places with no pond visible on map or photograph. Also small in number were confirmed in-filled ponds (between 2 and 10 ponds per parish) and for apparent drainage ditch locations.

Overall a similar pattern was obtained comparing the tetrad pond results with the parish pond results giving confidence in the findings. A small number of unmapped ponds were located, these being of varied size and representing up to about 1% of the remaining ponds.

In five of the tetrads a note was made of the number of extant mapped ponds that were too heavily shaded to determine (from aerial imagery) the continued presence of standing water, or that were located in remote locations within arable crops (generally 50–200 m from the nearest wood, grassland or hedge). Of the 145 ponds concerned 43 (30%) were classed as totally shaded or with water not visible from the aerial images and 22 (15%) located within arable field locations rather than natural or semi-natural habitat.

Ordnance Survey consultation Ordnance Survey were contacted to enquire about possible reasons for finding more references to the word ‘pond’ in the data supplied for the EN study than there were on the maps and aerial photographs, and also the multiple closely aggregated grid references for individual ponds. O.S. indicated that the revision of pond locations in rural areas is mainly carried out from aerial

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Figure 3. Newly excavated pond at Earth Holes Wood, Thorington in 2007.

Pond created as a part of land restoration following sand and gravel extraction.

imagery. Cartographic text including use of the word ‘pond’ is derived from their Land-Line data base which supplies their current MasterMap database.

The Landline database is made up of1km square units or ‘tiles’. Where the features on the edges of tiles meet, text is placed on both sides of the tile edge to ensure that if only one of the tiles is being used, it will still have the text information. Duplicate, triplicate or quadruplicate printing of the word ‘pond’ or ‘ponds’ may occur for those ponds that are located on tile edges, as the text is printed on each 1 km tile. Samples of ponds crossing lines were checked against the O.S. database used for the EN study and showed that larger ponds on grid squares that split over just two tiles had multiple grid references associated with them. The word ‘pond’ could appear four times or more in MasterMap if one pond falls across a junction of four different tiles. Further, for no apparent reason, some ponds had the word ‘pond’ written both inside the pond and outside the line demarcating its edge, even in ponds which did not cross grid lines.

In summary, analysis of the O.S. database using the word ‘pond’ to determine actual locations of ponds either currently existing or no longer present, appears to create an over-estimate of around 30%. These records appear to be largely duplicate references to single ponds. Another 10% of

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records refer to infilled ponds, possibly some filled several decades ago, ponds that have never existed or that are dry/seasonally flowing ditches described as ponds as a function of past recording techniques or recording error. Some may possibly be ponds within or along ditches that have been filled in or silted up and that are not visible today as ponds. The percentage accuracy of using the word ‘pond’ was very similar with the parishes and tetrad analysis. The frequency of these factors however varies from area to area. The O.S. database used for the 1999 EN study does not include a small proportion (around 1– 2%) of presumably both old and newly created ponds that are mapped but apparently without electronic supporting data.

Change in pond numbers and condition Pond persistence There is some evidence that woodland and parkland areas have retained more ponds and natural depressions than farmland, where natural undulations have been smoothed out. However, many woodland ponds, with or without water, are likely to be in a highly silted state and in some cases are present but not easily visible on the ground. Of the 46 ponds in Wolves wood near Hadleigh for example, few hold permanent water under a full tree canopy but may do so when the ponds are exposed during the early stages of open coppice rotation around the pond (R.S.P.B., pers. comm.). At the Groton Wood Suffolk Wildlife Trust reserve near Boxford, 13 ponds are shown on the reserve maps.

Three of these are enlargements of dry boundary ditches between the wood and arable land. Three others hold 200–500 mm depth of water. Of the other seven, two are damp or with just a few mm of water, and the other six are dry hollows. In summary, for these two woodlands just a few ponds remain wet and the majority are in a relatively redundant state for most pond wildlife species, for most of the time. These examples show that at any one time, only a small proportion of the ponds in woodland, perhaps locally as low as 10%, contribute to the ‘wet’ pond stock. This is not to say that mainly dry, semiseasonal or ‘autumn/winter’ ponds do not have intrinsic nature conservation value of their own.

Pond creation and restoration County Council pond restoration schemes ran from around the late 1980s until 2000 under a Landscape Conservation Grant Scheme. This mainly funded the de-silting of ponds at a rate of around 20 per year. European funding using European (Objective 5B programme) monies enabled an increased rate of pond de-silting and creation between 1999 and 2003. In this period Suffolk County Council reports the grant-aiding of the de-silting of 140 sites: 127 ponds and 13 moats. About half of the pond de-silting was in the Suffolk High Claylands in the north-east of the county. A further 17 ponds were created in that area. In terms of overall effort, an approximate annual average of 26 ponds/moats were de-silted in Suffolk between 1990 and 2003, using government sourced grant-aid.

Efforts by private landowners have probably more than matched government-funded projects in number, and particularly in dry/drought years when pond desilting may be many times the average but many have been

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Figure 4. Newly excavated pond at Dews Farm, Bramfield in 1997. stocked with ornamental fish or fish for angling. There are also some parish initiatives contributing to pond restoration. In Sibton, since 1998, the parish group ‘Trees, Hedges And Ponds In Sibton and Peasenhall’ (THRAPISAP) have restored about 10 key ponds, doing one or two each winter (R. Norton, pers. comm.). Pond creation occurs sporadically and there have been some local gains. At Dews Ponds SSSI/SAC in Bramfield, six new ponds have been created since 1997 and three more are planned in 2008. At Thorington Pit, Thorington, following sand and gravel extraction, six new ponds have been created and three enhanced since 2002 with designs suitable for expanding the great crested newt population present as a part of the general woodland and acid grassland landscape restoration. Other ponds may have been created or restored in Suffolk following mitigation for pond loss or disturbance to GCN habitat, licensed by English Nature and DEFRA but figures for these are not yet available. Assuming a 50 year cycle of pond de-silting, up to 250 ponds need management every year in order to ensure that ponds with a range of successional stages are maintained and to avoid the build up of a huge backlog of late successional ponds, many of which require attention.

Pond loss The EN study in 1999 suggested that ponds were lost proportionally across Suffolk, despite the SWT survey having previously noted considerably increased losses in the Ipswich area. There are few figures for pond loss rates

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in general, but those for great crested newt ponds probably reflect the general pond loss trend, at least until recently. The rate of pond loss over the decade 1989–1999 is not known precisely; a range of anecdotal indicators suggest that it was probably between 1–2% per decade overall, but with much variation across the county. This is a considerable reduction in the loss rate experienced in the 1980s and particularly the period 1945–1980 when average annual pond losses are likely to have exceeded 1%. However, the 1989–1999 rate still represents 10–20 ponds lost per year and exceeds conservation activity levels to create new ponds, resulting in a continued net decline in pond numbers. It is felt that the national Lowland Pond Survey reported national pond loss rate of 7% between 1990 and 1996 (over 1% per year) is not applicable to Suffolk. It may be the result of factors not acting in Suffolk, or it may be a consequence of the sampling squares selected having included squares with unusually high pond losses combined with extrapolation from a small sample size.

Funding Some District and Borough Councils have had pond schemes that, like the County Schemes, finished in anticipation of Stewardship schemes replacing them. However, the extent to which agri-environment schemes (including Higher Level Stewardship) will operate effectively is now in question, not least because land owners may now only restore ponds on condition of being accepted into Higher Level Stewardship (HLS) schemes. The monetary link between pond upkeep and grant aid has been established, but not funded to any significant extent, and this may be a very damaging development if funding is not now applied to the new system. Correct application of funding should be strategic and based upon pondscape management principles rather than a scattergun approach following random applications by landowners to agri-environment schemes. A recent bid to a Landfill Tax Credit scheme to establish another demonstration project in Suffolk did not go forward, partly for administrative reasons relating to the considerable lead time needed to engage landowners.

There is a need to emphasise the importance of pond creation as well as large scale pond restoration/de-silting. This may be a difficult balance to manage in practice but an important one. If large scale de-silting schemes get off the ground it will be important not to destroy in an uncontrolled way, ponds that might hold sediments with, for example, pollen or sub-fossil bone or shell records, that have archaeological value or that are places where late successional wildlife interest remain unrecorded. Properly managed pond restoration requires a series of checks and surveys to ensure this (see Langton et al., 2001). In many cases careful pond creation in appropriate locations is quicker, cheaper and holds fewer risks to wildlife. In practice, creation and restoration projects can be managed to best effect in tandem, especially when restoring pond clusters and pondways (sensu: Grayson et al., op. cit) where replacement of lost ponds as well as restoration is a strategic necessity.

Re-assessment of pond and newt numbers for Suffolk Pond numbers Both the SWT and EN studies failed to discriminate between freshwater and brackish or saline ponds. Examination of the O.S. maps indicates that this is

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likely to represent hundreds of ponds, including, for example, most of the dozens of ponds on Orford Ness, some of those at Minsmere and along the numerous creeks, saltmarshes and mudbanks of east coast rivers. There are probably many O.S. references in the EN study where temporary and permanent isolated or semi-isolated, brackish and saline waters are identified as ‘pond’ by the O.S field methodology/nomenclature and these were not discounted by either the EN or SWT studies.

The assumption that ponds under trees/woodland are all still present as viable ponds creates a considerable, but unquantified, overestimate. Both the proportion of ponds still present, and their state of wetness, are unknown quantities. The ancient Wolves Wood and Groton Wood examples used in this appraisal may not be typical of all woodlands.

A revision of the estimate for ponds present in Suffolk in 1999, based upon the findings of the tetrad study (in this appraisal) suggests a 38% reduction in number from the EN study, from 22,635 ponds to 14,033 ponds. However, further adjustments are required. The EN study did not include the cartographic text word ‘moat’ that comprises several hundred ponds in the SWT tally. There are reported to be around 770 moats in Suffolk (Dymond & Martin, 1989). Some are dry but others broken into separate sections so there is no precise figure for wet moats. Assuming that parts of moats were not named as ‘ponds’ by O.S,. adjusting upwards for moats may contribute a ‘guess-estimated’ additional 500 water bodies to the freshwater pond numbers in Suffolk.

With corrections for inaccurate grid referencing, the EN study estimate initially falls very close to the 1990 SWT estimate of 15,400 mapped ponds for Suffolk The EN study considered that the SWT review used maps that might not include all of the ‘ponds‘ known to Ordnance Survey due to their “small size, difficulties in plotting clusters of ponds or insufficient space” and that “the information of the digital database is more accurate than the information on paper maps produced from it.” The first statement will require further research to determine how much size has affected inclusion on maps. It raises a question of the cut-off size for ponds to be included in analysis, and the inclusion of garden ponds and dry or temporary ponds/wet depressions in the ground. The existence of numbers of small ponds between the smaller sized rural ponds and garden ponds size does not actually occur in the field to any great extent and that the conclusion drawn in the EN study to explain the number of ‘pond’ grid references is unsubstantiated. The few unmapped ponds found from grid references were generally larger than 5 m in diameter. The second statement regarding the greater accuracy of the digital database is now known to be incorrect. Applying adjustments to the SWT estimate suggests the number of ponds in Suffolk in 1999 was probably close to 12,320 ponds with the EN study based adjustments indicating slightly more but not having been subject to ground truthing. The revised estimate for ponds in Suffolk in 2007 is 11,500 plus or minus 1000 ponds. The actual number of ponds that still hold water for 4–7 months per year or ‘wet ponds’ is likely to be less than this and will relate to the overall proportion of ponds in woodland/under dense trees and their status, which requires further research. The ‘wet pond’ estimate for 2007 is 9,240 but could be lower.

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Newt numbers To get some idea of GCN pond survival over the decade from 1990 to 1999, a sample of the GCN breeding ponds recorded in the SWT GCN Site Register from 1990 was reviewed by sampling to see how many of them still appear on the late 1990s aerial satellite/photographic images. These records were a combination of the current Suffolk Biological Records Centre (SBRC) records and those collected by the Suffolk Wildlife Trust field survey work in the late 1980s (mainly 1987–1989) . Sixty two records were randomly sampled and checked, this being about half of the records on the GCN register for 1990.

The check was made to see if the ponds were still showing on the late 1990s aerial images, although their continued suitability for great crested newt could not be checked, just the continued survival of the pond. Results showed that 50 (81%) of the ponds were either definitely present (n = 37) or under woodland canopy and probably still present (n = 13). Of the 12 remaining records one was a pond definitely lost to infilling and one part in-filled, the rest being ponds not in woodland but not visible under tree canopy and requiring field visits to assess. These are presumed to remain but further checks are needed. Five ponds near to GCN ponds had been lost but it was not possible to state whether this had been done since 1980, nor whether they were occupied by GCN. Within 100 m or so of the edge of three GCN ponds, there was terrestrial habitat reduction for house building. Another three ponds were partly in-filled or damaged and two had been fully restored. Two new shallow lakes had also been created.

The GCN records review suggests that, for this small sample at least, the loss of recorded GCN ponds over the decade 1989–1999 was running at a rate of slightly over 1% per decade and known GCN pond partial infilling at up to around 3% per decade. While new pond/lake creation was running at about the same low rate as pond loss it is not clear if the new large ponds/lakes are of any value to GCN. Restoration of recorded GCN ponds appears to be running at up to 3% per decade although there are concerns that restored ponds may have had fish added to them. Ground checks in 2007 revealed that at least one pond had been carefully restored for GCN by a farmer in knowledge of their presence, but one had been too intensively restored/over-deepened.

Elsewhere in Suffolk and subsequent to the 1990 analysis, the authors have noted one (previously unrecorded) GCN pond being almost completely infilled having been slowly filled since the 1970s, two GCN ponds being partly (about one third) in-filled, one with soil and one with rubbish, and one shallow pond within 50 m of a known GCN breeding pond being in-filled. Another five GCN breeding ponds identified since 1990 are known to have been desilted, but afterwards stocked with fish (Carp & Rudd). This includes one instance where the de-silting was part-funded by a Council grant.

The pond survival checks conducted by SWT in the late 1980s were accompanied by GCN pond occupation surveys carried out by trained volunteers. For the survey, 82 of the 111 ponds remaining were surveyed and GCN occupancy was at 4¡9% in that sample. Smooth newt was twice as apparent at 11% occupancy. The more recent SWT Suffolk Ponds Project survey sample of 500 ponds (Meade, 2005b) found GCN occupancy in 10% of

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ponds. This survey has been extended to around 1000 ponds and GCN occupancy rates have fallen below 10% (Hawkins 2006) level. A major concern is that many ponds created in recent years have been stocked with fish by owners, largely unaware of the limitations this brings to the aquatic species capable of surviving fish predation in small closed waters. Surveys by Suffolk Amphibian and Reptile Group members have found that ponds created using grant aid have a limited value to wildlife due to fish stocking, a factor apparently uncontrolled during the period of additional funding.

Applying a 10% pond GCN occupancy rate to the 2007 Suffolk pond number estimate and the probable wet pond numbers for Suffolk, gives a figure of 1000 breeding ponds plus or minus 250 ponds. The range caters for the uncertainty of the exact status of woodland ponds. As a final note it is worth mentioning that the recent SWT appraisal of the size of GCN populations (number of individuals per pond) is generally considered to be very small due to the highly degraded state of many remaining ponds (D. Casey, pers. comm.). Small populations may result in inbreeding and further problems for species recovery resulting from isolation, fragmentation and genetic bottlenecking of GCN and other pond species.

Future conservation measures and recommendations The EN study and a figure of ‘over 22,000 freshwater ponds in Suffolk’ has been quoted in a number of publications since it was produced in 1999, (Meade, 2005a; 2005b, Suffolk Wildlife Trust 2004) and seems to have been generally promoted as a ‘good’ representation. The more likely situation, as described here, now requires articulation to county and national interest groups as there is good evidence that pond conservation status and conservation needs have been seriously underestimated. The condition of standing freshwaters for aquatic wildlife in Suffolk can only be described as being in crisis, the result of inadequate nature conservation action. This review finds that pond numbers and GCN populations continue to decline and, while the loss rates may have slowed to some degree in recent years, net losses in pond numbers need to be halted as a priority and pond management and creation needs to be addressed on a large scale.

Recommendations 1. Defra/UK government There is now a distinct shortfall between the need for pond and ‘protected pond species’ protection and the implementation of required measures. This is despite the backdrop of a clear legal mandate to the UK government in both the Berne Convention (for approaching 30 years) and in EU law (for over 10 years) towards GCN and other pond species. The 2005 legal judgment in Case C-6/04 Commission v United Kingdom ruled (amongst other things) that the species protection provisions in the Habitats Regulations were not compatible with the strict species protection regime required by Articles 12 and 13 of the 1992 Habitats Directive. In July of 2007, the Conservation (Natural Habitats & c.) (Amendment) Regulations 2007 were laid before Parliament requiring the Secretary of State to make arrangements for better surveillance of the conservation of species of community interest including great crested newt.

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With Suffolk as a key example of the plight of great crested newt and its habitat in the UK, and a casualty of poor surveillance, it is not unlikely that new action will be taken to encourage the UK government to meet its obligations to monitor the great crested situation far more accurately and not to continue to withhold funding for realistic and properly resourced recovery programmes.

2. Ordnance Survey The main conclusion from the EN study re-evaluation has to be the need for Ordnance Survey to update and maintain to a better level of accuracy their information on ponds. This large organisation should be encouraged to do so as a badly needed contribution to biodiversity protection in Suffolk and the UK in general. Ordnance Survey has indicated that they are currently undertaking improvements to their database that will, in time, remove the duplication discovered by this review. (A. Roberts, pers comm.) This work could be done in partnership with voluntary groups to assist field work.

3. E.A There is good evidence of need for the Environment Agency and other government agencies to enforce controls which aim to prevent the release of fish into ponds or ‘controlled waters’ without a licence and to co-ordinate the removal of fish when they are discovered. The methods for doing this may be difficult and costly at the outset but they are essential to the control of this apparently increasing problem. Public information and education is needed to create better awareness of the issues involved and to help limit fish stocking.

4. Voluntary bodies Suffolk Wildlife Trust has played an important role in researching and publicising the plight of ponds and great crested newts. With public support, the Trust has been able to provide advice on conservation needs at an individual level, but access to financial help and practical solutions has been very limited. Government help and financial support is needed on a substantial scale. A parish by parish appraisal of ponds along the lines of that used for hedgerows could be promoted to better define detailed local pond conservation needs and to inform agri-environment schemes once properly funded. In the meantime lobbying for action must be the immediate priority.

Acknowledgements Angela Roberts, Customer Service Advisor, Ordnance Survey, Southampton; John Davis, Suffolk Coastal District Council; Peter Holborn, Suffolk County Council; Rosie Norton, Thorington THRAPISAP; Suffolk landowners; R.S.P.B., Nick Sibbett, Natural England; Dorothy Casey and Juliet Hawkins, Suffolk Wildlife Trust. The original SWT surveys were part-funded by a grant from the FFPS/SEH Herpetofauna Working Group Fund, supported by the Vincent Wildlife Trust.

References Brain, A. & Harding, B. (1996). A survey of Herefordshire Ponds and their value for Wildlife 1987–1991. Transactions of the Woolhope Naturalists’ Club XLVIII, Part III.

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Boothby, J. & Hull, A. P. (1997). A census of ponds in Cheshire, North West England. Aquatic Conservation: Marine and Freshwater Ecosystems 7: 75–79.

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Langton, T., Beckett, C. & Foster, J. (2001). Great Crested Newt Conservation Handbook. Froglife, Halesworth.

Meade, N . (2005A). Great crested newt surveying with the Suffolk ponds project. White Admiral 60 Spring 2005.

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Suffolk Wildlife Trust (1990b) A conservation strategy for reptiles and amphibians in Suffolk PART1 Distribution of the native Herpetofauna of Suffolk. Prepared for SWT by C. L. Beckett and T. E. S. Langton, HCI, Halesworth, Suffolk.

Suffolk Wildlife Trust (1990c) A conservation strategy for reptiles and amphibians in Suffolk PART 2 Assessment and recommendations.

Prepared for SWT by C. L. Beckett and T. E. S. Langton, HCI, Halesworth, Suffolk.

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Tom Langton Dews Farm Bramfield Suffolk IP19 9AE E-mail: t.langt@virgin.net

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