Haslemere Bioblitz 2019 Report
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Haslemere Natural History Society Haslemere BioBlitz 2019 Report Introduction The first Haslemere BioBlitz took place in the period 28-30th June 2019, targeting the area within 1km of Haslemere Town Hall, and was organised by Haslemere Natural History Society (HNHS). There was particular focus on the grounds of Haslemere Educational Museum and the National Trust’s Swan Barn Farm, with support from those two organisations. The intention was to involve invited experts, HNHS members and the general public in the search for as many species of macroscopic organisms as possible. The purposes of the event were both a) scientific – to establish a base-line of data and potentially to discover species of conservation significance; and b) educational – to involve and enthuse people in the study of our local biodiversity. Methods Schedule The event compiled records of species sighted in the period 10.00am Friday 28th June to 10.00am Sunday 30th June. Records from HNHS members, invited experts and the general public were welcomed for the whole of that period, but there were thematic events on these days for HNHS members and/or the public that also generated data. On 28th June, the weather was sunny but breezy. 29th June was very warm, and was followed by a warm, humid night. Field Techniques In addition to general observation and searches, the following focussed techniques were used: Camera trap: an infra-red “trail camera” was used in the Museum grounds and in woodland close to Swan Barn Farm. Bat detectors: heterodyne detectors were used during a bat walk at Swan Barn Farm; an ultra- sound recording and automatic diagnosis system was used overnight at a Haslemere house as well as during the bat walk. Moth traps: a Skinner trap with actinic light source was sited at the Museum on the first night, and then adjacent to Swan Barn Farm on the second night; a Robinson trap with Mercury vapour bulb was sited just inside woodland close to Swan Barn Farm on the second night only. Pitfall traps: a number of plastic cups were sunk under trees in the Museum’s grounds. Sweep nets: these were deployed largely along hedgerows and in meadows during insect-themed public and HNHS events in the Museum grounds and on Swan Barn Farm land. Pond “dipping”: nets were used in the large pond in the Museum grounds. Small mammal footprint tunnel: a cardboard tube with ink pads to record small mammals was baited with sunflower seeds (for rodents) and cat food (for hedgehogs) and deployed in the Museum grounds, but was destroyed by a domestic cat. Omissions Small mammal traps such as the Longworth were not used due to the chance of mortality; as the footprint tunnel failed, there was no survey of small mammals. A survey of lichens was intended at key sites (such as St Bartholomew’s churchyard), but did not occur due to time constraints. Some mosses and fungi were noted, but the time of year is not the best for these groups, so detailed surveys were not planned. Other groups were not well surveyed due to limitations of expertise and time; these included the smaller diptera and parasitic wasps. An authority on earthworms was invited but was unable to attend. Personnel The following were the main contributors to the species list, with their principal areas of expertise. (The indicated initials are used in the following text and Appendix). Matt Bramich (MB): moths June Chatfield (JC): gastropods Scotty Dodd (SD): insects Mike Lawn (ML): insects and birds Keith Lugg (KL): isopods and myriapods Simon Moore (SM): arachnids Judith Moss (JM): vascular plants Martyn Phillis (MP): bats Andy Swan (AS): vascular plants Results Biological Data 512 species were recorded; these are listed in the Appendix. This includes a few specimens that were not identified to species level (whilst ensuring no double-counting). A summary of the observations in major categories of organisms follows. Mammals: The 14 species of mammal found included seven species of bat detected by MP, including the rare Western Barbastelle. The overnight camera trap yielded a fox in the grounds of the museum and a badger in woods near Swan Barn Farm. Birds: The 27 species seen did not include any surprises. Hirundines were notably absent, and just one party of seven Swifts were observed. Other notable absences were House Sparrow and Chaffinch, both species still recovering after regional population crashes. Lepidoptera: Among the 86 species recorded were ten common species of butterfly, of which only the Meadow Brown was seen in numbers. Hopes of finding Purple Emperors or White Admirals were not realised. The moth records were nearly all from light traps, and the vast majority of these were from Swan Barn Farm on the second night (the light trap at the museum yielded just four species). The moths included the spectacular Privet Hawkmoth and a number of less common species, such as Poplar Lutestring, Treble Brown Spot, Scorched Wing, Great Oak Beauty (nationally scarce), Coronet, Triple-spotted Clay and the micromoth Pandemis dumetana. The predominant general habitat affinities were damp oak woodland plus a damp grassland component. Other insects: The variety of other insect species recorded was largely the product of sweeping in the museum grounds by SD and in Swan Barn Farm hedgerows by ML. Highlights were the uncommon “picture-wing” fly Rivellia syngenesiae and the Umbellifer Longhorn Beetle Phytoecia cylindrica, both in the Museum grounds. However, the general impression of surveyors was that flying insects were not as abundant as expected. Other invertebrates: The expertise of SM was largely responsible for a list of 25 spiders, including the infrequent Pirata hygrophilus. The marshy slope below Haslemere Town Well was the source of many of these records. KL is a national authority on isopods and myriapods, and he was the major contributor to a healthy list of six woodlice, three centipede and three millipede species, but none of these were unusual. The search for terrestrial and freshwater gastropods by JC was the basis of a total of 25 species. The damp slope just referred to was a significant habitat for these, and a specimen of Oxyloma found here may prove to be the rare O. sarsi, a first for Surrey, but this is still subject to confirmation. Plants: The vascular plant list has 204 species. Of these, 33 are non-native (mostly garden escapes), which is unsurprising considering the inclusion of Haslemere town in the survey area. The list is dominated by common species, but Trailing Tormentil Potentilla anglica is a significant record – a new record for the tetrad. The botanically richest habitats were the damp meadows, ditches and streamsides. Although non-native, Himalayan Honeysuckle Leycesteria formosa and Himalayan Knotweed Persicaria wallichii are interesting and unusual records. The species list will be sent to the Surrey Biodiversity Information Centre, who have agreed to add the data to the national database. Education and Outreach The involvement of the public was disappointing, with very few tickets sold for the organised events, and few casual “drop-ins” to the Museum. The reasons for this are unclear: the advance publicity was of good quality and used diverse media. However, those who did join in (all in SD’s event in the museum grounds) had a high-quality and productive event. Hopefully, wildlife awareness in Haslemere was enhanced by the follow-up double-page article in the Herald newspaper. Summary for Haslemere Educational Museum Surveyors reported a good range of diverse organisms associated with the damper areas on the lower slopes of the grounds. The pond appears to support a rich ecosystem, including newts and the spectacular Great Diving Beetle. The Small China-mark and Bulrush Wainscot moths that were recorded as flying adults have larval stages that feed on pond vegetation. The damper lower parts of the “meadow” area (beyond the ha-ha) yielded the uncommon picture-wing fly and longhorn beetle referred to above, but the drier parts were thought to be quite disappointing. The light trap set up at the back of the Museum yielded the interesting and uncommon Lobster and Scorched Wing moths, both associated with deciduous trees, along with Heart & Club moths, which is a common grassland species; the list of just four species represents a very poor yield for the time of year. Very few birds were seen using the grounds. It is recommended that the current pond management regime is continued, but that the “meadow” could be better managed as a wildflower meadow, with consequent benefits to insects and other wildlife. This could be both an attractive feature and an educational resource for visiting children. Summary for Swan Barn Farm The most productive habitats in Swan Barn Farm’s land were the damper areas. The dominant habitat with which the less common moths were associated was found to be damp oak woodland, plus to a lesser extent damp grassland. The light traps demonstrated a healthy abundance of insects, and this is no doubt the basis for the occurrence of the seven bat species, including the rare Western Barbastelle. The drier parts of the fields were generally not very biodiverse, although it is likely that their current state represents a recovery from a history of drainage and application of agro-chemicals. There are some fine hedgerows, and the trackside ditch between the pond and the farm has a good selection of plants. However, the most interesting area, according to several specialists, is the marshy slope east of the spring/seep line (at the boundary of the Lower Greensand and Atherfield Clay) between Town Well and the museum grounds. This was the best site for arachnids and terrestrial gastropods, and it is thought that the flora, which is already interesting, has potential to develop further with sympathetic management.