Bringing Geology to Life in Halton. Report 3, December 2008

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2 Bringing Geology to Life in Halton Report 3, December 2008 Cover illustration: Bluebells Hyacinthoides non-scripta., a species of conservation interest in Halton. Courtesy of Steve McWilliam

3 Introduction At the end of report two, the next steps for taking Bringing Geology to Life in Halton were outlined. Having created an inventory of geological sites of interest in Halton, the next stage is to compile data on the biodiversity for the sites and then select the sites which are to be given display boards. Biological Records for Geological Sites in Halton The Record database already holds over one hundred thousand species records for Halton. Throughout 2008, this database has been augmented by the addition of new and up to date species records specifically for sites of geological interest. From this data, species lists have been created for all the sites of geological interest in Halton; an important task as it provides information on the biodiversity of the sites and any notable or protected species. This process also feeds into the Local Wildlife Sites system for Halton, which is administered by the Borough Council and provides information on the natural history of various sites of interest across the Borough. Two of the sites covered by this project have been identified for the production of Local Wildlife Site citations, which will use the species lists and the geological information compiled by Bringing Geology to Life in Halton to create documents that are used to inform planning and development decisions. The two sites in question are Halton Castle and Liverpool road former Quarry, Widnes, and the citations themselves will be completed by the end of December The full species lists for all the sites covered can be found in the appendix, but the report itself will summarise the most interesting species recorded at each site. The order of the sites is the same as that of Report 2, and the map at the beginning of that report can be used locate the sites. The summary of the species themselves includes a note of species that appear on national designation lists. These lists are the United Kingdom Biodiversity Action Plan, the Natural Environment and Rural Communities Act (2006) and the Wildlife and Countryside Act (1981). For more information on what these lists mean, see the appendix. More generally, by looking to see what lists recorded species may fall under, a picture can be gained of how significant a site is for wildlife. Species appear on the various lists because their population is declining and under threat, and as a result action needs to be taken. Some species are singled out for specific legal protection (such as badgers and bats) or the hunting, trapping or disturbing of these species is controlled. These species appear on the Wildlife and Countryside Act of Sites 1. Rock Park, Sewell Street, Runcorn This is a well recorded site, with 128 different species having been recorded. The records are well spread between plants and invertebrates and with a few birds also being recorded. One of these birds, the house sparrow, is one of the most significant species to be recorded at the site. This bird has undergone a noticeable decline in recent years and for this reason it is a UK biodiversity action plan species. It is also protected under the Wildlife and Countryside Act of 1981.

4 Rock Park is a recreational area and many of the species recorded for the site reflect this. There are records of trees and the common shrubs and plants that are often found in and around public parkland such as bramble and white clover. Although a well recorded site there are few species that suggest that this site is of high value for Wildlife, with the house sparrow being the only species of particular note. 2. Glacial Erratic, Palacefields Avenue, Runcorn. Although the geology at this site is not remarkably varied and interesting, the species records are certainly noteworthy. The site is wooded, with a nearby pond and this is reflected in the species list, with plants such as hazel and common duckweed present. There are also aquatic invertebrates present (e.g. Azure damselfly) but no terrestrial ones. Vertebrates are represented by fish (presumably in the nearby pond) amphibians and birds. The common frog and smooth newt are two protected amphibians recorded at the site and the song thrush is a protected bird. Although the song thrush is not on the UK BAP list, it is worth noting that Halton Borough council also operates a BAP list of its own which includes the song thrush. In total there are sixty eight species records for the site, and three of these are of protected species. A less well recorded area than Rock Park, the area around the glacial erratic has more records of protected species, suggesting that it may be of more interest to wildlife conservation. However, it is hard to see how these species relate to the geology itself and may be more closely connected to the nearby pond. 3. Halton Castle, Runcorn Halton Caslte is situated on a sandstone outcrop and is surrounded by bramble scrub, houses and gardens. There are only 27 species recorded here, and none of them are of any particular note. The surrounding habitat is well represented by the records, with species such as bramble, hawthorn and stinging nettle appearing in the species list. 4. Manchester Ship Canal Bank There are 33 species recorded for this site, some of which are particularly interesting from a conservation point of view. The records are mostly of plants and birds, but there are two species of spider recorded and one snail. Within the list of plants there are three (Sea Purslane, Sea Plantain and Sea Aster) which are maritime species and survive in salty conditions. When these plants are found inland, it is often because the local geology has created an unusually saline environment. However, the existence of these species at the Mersey Ship Canal bank owes more to the proximity of the site to the Mersey estuary than the geological conditions. The interesting animal species that are recorded here are smooth newt, dunnock and linnet. All three are protected species and dunnock and linnet are noted for conservation concern. The presence of these species is probably due to the adjacent nature reserve which is managed particularly for wildlife. 5. Weston Piont Expressway

5 This large cutting has revealed a large amount of rock, but unfortunately is relatively inaccessible due to the main road that runs along side it and the fact that it is a sheer rock face. This makes recording any biodiversity difficult, hence there are only two species recorded for the site. One of these species is Danish scurvy grass, which is not a native to the UK and has been spreading along the road network over recent years. It is another plant that is able to utilise a more salty environment and spreads along road networks because of the grit salt that is applied to them in the winter. The presence of this species at the Weston Point Expressway site is due to the adjacent expressway rather than any particular geological feature. 6. A56 near Daresbury There are sixty recorded species here, comprising a mix of fungi, plants, invertebrates and vertebrates. The surrounding area is on one side, agricultural and on the other side a main road. As a result, much of the wildlife is associated with hedgerows with species such as foxglove and hogweed belying this fact. Common ragwort is another plant often found in these conditions, and this too is recorded at the site. It is particularly significant as the food plant of the cinnabar moth, which became a UK Biodiversity Action Plan species in The cinnabar itself has also been recorded at this site, and is the only species of particular note for wildlife conservation interest. There are two species of ant recorded at this site, and this may be due to the presence of the sandy soil created by erosion of the sandstone. 7. Keckwick Hill 268 species have been recorded at Keckwick Hill, owing much to the fact that it is nestled in Daresbury Firs Local Nature Reserve. The records cover flora, fauna and fungi in some depth, including more primitive plants such as mosses and liverworts. These plants are often associated with geological sites, especially particularly wet ones. The bare surface of rock is hard for larger plants to get a foothold on, and only where cracks in the rock allow the accumulation of soil can bigger plants get established. Mosses and liverworts do not require an accumulation of soil and as a result are able to grow on the surface of bare rock. Their only requirement is that enough water is available, which is often not a problem on sandstone as it is able to allow water to pass through it. Keckwick Hill is a former quarry site and as such has revealed bare rock faces which provide a niche for mosses and liverworts, allowing for the 35 different species of this group (Bryophytes) that have been recorded in the area. Daresbury Firs Local Nature Reserve is a woodland nature reserve, and as the name suggests, contains a lot of coniferous trees. There are six species of coniferous tree recorded around the Keckwick Hill area, creating a shaded woodland habitat. In shaded areas, plants such as bracken and fern are able to thrive. These too have been recorded at Keckwick Hill, and are of particular interest as they, like the bryophytes are often associated with rock exposures. Ferns can often get a foothold in the smallest of cracks and manage to survive in areas where there is a lot of shade, unlike most other plants which require a certain amount of sunlight. Geological sites are

6 often shaded, especially cuttings and former quarries, and this provides a good environment for ferns. Of the seven species recorded at Keckwick Hill that are of particular conservation concern, six of them are birds that would be expected to be found in wooded areas, such as the song thrush and the bullfinch. The other species is a protected plant species, the English bluebell. Native English bluebells are now under threat as they are hybridising readily with a Spanish species. For this reason, they are protected by law. The sheer number of different species recorded at Keckwick hill makes it an interesting site, but perhaps more importantly than that is the fact that many of these species (such as the bryophytes) are associated with the geological conditions. 8. Blackheath Lane Ponds, Near Moore This is a small site, where the geology in question consists of a deposit of pure sand. It is near a ditch near an industrial site and only has one recorded species, the water vole. Water voles are protected and of particular conservation interest. They are found near freshwater bodies such as ditches but are unlikely to be affected much by the surrounding geologic conditions. 9. Stenhills Open Space, Runcorn This is an extensive site and features parkland scrub habitats. The large amount of species recorded for the site (273), perhaps reflects the overall size of the area. Many of the species are plants that are associated with this type of environment, such as bramble, blackthorn and the non-native invasive species Japanese knotweed. In fact this assemblage of shrubs and scrub species has largely overgrown the rock faces, making it very hard to record any species growing there (if indeed there are any). In terms of animal interest there are many species of invertebrate recorded including slugs and snails, insects and spiders. There is also a set of bird species recorded for the site, which includes robin and blackbird and other species common in urban scrub and parkland. Despite the large number of different species, none of them are of particular conservation interest and none of them are particularly indicative of the geology of the site other than some species of fern. This could be helped by the removal of some of shrubbery to open up the rock faces and provide better access to wildlife recorders. This may also create an opportunity for some interesting bryophytes to colonise the rock. 10. Red Brow Cutting This site has 85 species recorded, consisting of plants and animals. Amongst the plants are liverworts and ferns such as the hart s tongue fern. Red Brow Cutting is a moist and shady environment, providing good conditions for ferns (such as the harts tongue) to establish themselves in the cracks in the rock. From visiting the site, the relationship between the water and the liverworts growing on the rocks is clearly

7 visible. Rocks oozing water tend to be much greener with a covering of algae (species that are hard to identify and therefore not recorded) and liverworts. The habitats around the site are fields, woods and hedges. The woods and hedges provide a suitable habitat for bluebells, a protected species, whilst the surrounding fields are home to lapwings, another protected species. Whilst these species are of interest for wildlife conservation, they are not related to the geology of the site. 11. Liverpool Road Former Quarry Of the 53 species recorded at this site, most are plants. The wildlife of the area is heavily oriented towards the kinds of species found in urban areas. Plants such as white clover and dandelion are often found in urban park and grassland, and are recorded at this site. There are two UKBAP and protected species both of which are birds, and both of which are also associated with the urban environment. The house sparrow and starling provide the only real wildlife conservation interest for this area. There are no species on the species list that particularly represent the links between the biology and the geodiversity. 12. Hale Lighthouse This site consists of the rock between the Mersey estuary and the agricultural areas of Hale. These habitats are represented in the species list for Hale Lighthouse, with estuarine plants such as lesser sea-spurrey and sea milkwort living near the water, and birds such as skylarks in the fields further back. The rocks themselves have been weathered by the tide and are smooth with only algae growing on them. The sandy soils on top of the rocks provide a home for certain invertebrate species such as ants and bees. There are two species of ant and two of bee recorded here, along with other interesting invertebrates such as butterflies. One of these, the Wall, is rare species and very important for conservation. However, this probably hasn t been recorded here for a while. Other species of conservation interest come from the list of birds. Six of these species are associated with the farmland around the site, but two others, the lapwing and the curlew are also associated with the estuary and its mudflats. Selecting Sites for Display Boards Having compiled information on sites of geological interest in Halton, a decision can be made on which sites to choose for display boards. In order to aid the selection process, a discussion group was formed that graded the sites in question according to set of criteria and then discussed the outcome. The grading system used was a numerical system and was inspired by the system of auditing used by geologists to assess Regionally Important Geological and Geomorphological Sites (RIGS). Scores of one to five were given to each site for various criteria and the resulting data were tabulated. The results of this process are summarised in the table below.

8 Access and safety MSC Bank Rock Park Stenhills A 56 Road access and parking Safety of access and exposure Permission to visit Education and science Geological processes (Bedding, Weathering etc.) Human history (Quarrying and chisel marks etc.) Biological processes Total Access and safety Redbrow Kecwick Hill Hale Lighthouse Liverpool Road Road access and parking Safety of access and exposure Permission to visit Education and science Geological processes (Bedding, Weathering etc.) Human history (Quarrying and chisel marks etc.) Biological processes Total The result of this exercise was to prompt further discussion and to asses which sites may not be feasible boards due to land ownership issues. It was decided that the high scoring Keckwick Hill site, which is also close to the high scoring A56 and Redbrow cutting sites would be ideal and for display boards as it could also contain information on the other two sites. In the interests of community involvement, it is important to spread the project over Runcorn and Widnes, so the highest scoring Widnes site has also been chosen as an ideal candidate for placing of display boards.