CARAVAN CLUB ECOLOGICAL SITE APPRAISAL
General Information Site Name and County: Low Park Wood Caravan Club Site, Cumbria Grid Reference: SD 509 878 Area: 8.09 hectares Date: 18/06/06 Recorder: Vilas Anthwal, JUST ECOLOGY Weather Conditions: Overcast, warm.
Low Park Wood Caravan Club Site
Site Description The site is located approximately between 20-40m above sea-level and comprises a mainly wooded habitat on the west bank of the River Kent. The topography of the site is moderately sloping east facing banks in the west of the site, leveling out to a flat river flood plain in the east of the site. The site has 161 pitches on hard standing surrounded by fragments of amenity grassland. Maintenance buildings are concentrated in the south-east corner, with the exception of two toilet blocks, and caravanning pitches are distributed fairly evenly across the site. There several are woodland walks running throughout the site. Context The site is within the Cumbria Fells and Dales Natural Area (www.englishnature.org.uk) and more specifically is within the Morecombe Limestones part of this Natural Area. This comprises the limestone country surrounding Morecambe Bay which extends from Furness to Carnforth. The landscape is characterised by upstanding blocks of limestone with scars, cliffs, scree and limestone pavement, separated by fertile valleys and broadleaved woodland. There is species-rich limestone grassland, often with pockets of limestone heath and juniper scrub, and the limestone pavements are obvious nature conservation features. Semi-natural woodlands are characteristic of this area and where these form mosaics with the grasslands and pavements they can be particularly important for invertebrates such as butterflies. Lime-rich marl lakes, a rare habitat in Britain, are also found in these limestone areas. The head of the Leven and Kent estuaries, which form part of Morecambe Bay, have extensive areas of lowland raised mire. However, many of these have been cut over for domestic peat or reclaimed for agriculture. At Leighton Moss reclaimed peatland has been re-flooded and the areas of open water and reed-bed that have developed support rare birds. Adjacent to the site there is one SSSI (Site of Special Scientific Interest), River Kent and tributaries SSSI. Further afield (but within 3km) is the Scout and Cunswick Scars SSSI. The Scars are made up of a complex of limestone habitats which support a very rich fauna and flora including a number of rare and local species. The main habitats present in this SSSI are unimproved calcareous grassland and areas of dry dwarf shrub heath with scattered trees and shrubs, woodland, open water and fen. The assemblage of habitats can be regarded as unique in Cumbria (www.englishnature.org.uk). The nearest designated site, River Kent and tributaries SSSI, support nationally important populations of whiteclawed crayfish Austropotamobius pallipes. One of the headwaters also supports one of the largest populations of fresh water pearl mussel Margaritifera margaritifera in England. The rivers main tributaries have their catchments in the south eastern Lake District fells. On the higher ground these drain from rocks of Ordovician and Silurian age. Natural mineral enrichment provides the calcium necessary for growth of crayfish. Downstream from Kendal, the main channel of the Kent flows through a series of limestone defiles and gorges. This stretch is influenced by calcium-rich limestone springs. White-clawed crayfish are found throughout the river system, from the headwaters of the Rivers Kent, Gowan, Mint and Sprint downstream to the lower reaches of the main Kent channel near Sedgwick. The Kent is the only major river system in England where populations of white-clawed crayfish can still be found throughout the catchment, wherever there are suitable habitats and at high densities. Within the Kent catchment, crayfish are found
in the lower reaches near sea level up to at least 250m above sea level in the headwaters of the Rivers Kent and Mint. Dubbs Beck, the headwater of the River Gowan, also has populations in two small reservoirs. The Kent system presents a variety of habitats for crayfish. This includes extensive areas with a loosely structured but stable stream bed of cobbles and stones. Crayfish are also found in the more unstable, turbulent reaches of the upper Kent and Sprint wherever there are small areas of cobbles and stones at the edge of channels. In the lower reaches, and particularly through Kendal, there are extensive beds of water crowfoot Ranunculus spp and alternate-flowered water-milfoil Myriophyllum alterniflorum providing a further habitat and food source for crayfish. In the headwaters of the River Gowan, populations are found in streams less than a metre wide with only a few centimetres depth of water. This contrasts with the lower stretches of the main Kent channel where crayfish are found in much deeper water amongst boulders and shattered bedrock. The main channel of the River Kent has extensive reaches with undisturbed riparian habitats of woodland and tall riparian vegetation. Much of the river system is lined with tall, marginal vegetation of reed canary-grass Phalaris arundinacea, hemlock water dropwort Oenanthe crocata and associated tall herbs and grasses. The submerged roots of these plants, and the diversity of habitats created by the riparian vegetation, provide excellent refuges for crayfish. Apart from the quality and extent of habitats, the Kent is an excellent river for crayfish for a number of other reasons. The Kent and its tributaries have generally high water quality. With a short distance from the headwaters to the mouth of the river, and heavy rainfall on the catchment fells, the river has a high degree of flushing. This maintains the river bed relatively free of silt and algal growth. This means the spaces between and under river stones and cobbles provide excellent habitat for crayfish and their invertebrate food. Finally, the Kent catchment is free from introductions of non-native crayfish and there is no record of crayfish plague. Although white-clawed crayfish is still present throughout most of its natural range in England, there are only three catchments where this once common freshwater crustacean can still be considered to be abundant and widespread. These are the Eden and Kent in Cumbria and the Wye on the English/Welsh border. In other catchments, populations are small and scattered or under threat from non-native crayfish and crayfish plague. Apart from the impact of non-native crayfish, declines in water quality, loss of natural riparian habitats and river channel modifications have all led to declines in crayfish populations. Freshwater pearl mussels are also found together in one of the upper tributaries. The Kent system supports one of only two populations of pearl mussel in England which are currently known to be recruiting young mussels. Freshwater pearl mussels can live for over 100 years. Their life cycle is however complex and in part dependent upon the maintenance of a healthy salmonid population. Populations of freshwater pearl mussels are aging and declining across their European range. This is attributed to pollution, alterations to river channels, changes in flow regimes, exploitation and decreasing salmonid numbers. The populations within the UK are now considered to be of international importance.
Habitat Information Broad Habitats Present: Broad-leaved Woodland, Improved Grassland. BAP Priority Habitats Present: Upland Ashwood with National Vegetation Classification (NVC) affinities: W8 Fraxinus excelsior- Acer campestris- Mercurialis perennis woodland. Subsidiary Habitats Present: Tufa springs. Grassland Communities: There were no extensive areas of grassland and the site had a predominantly woodland character. Where grassland was present it was confined to small mown clearings and the edges of caravan pitches (Figure 1). The sward here was re-seeded as amenity grassland dominated by Perennial Rye Grass Lolium perenne and Common Bent Agrostis capillaris, and herbs such as Daisy Bellis perennis, Creeping Buttercup Ranunculus repens and Greater Plantain Plantago major.
Figure 1 Mown grassland at the woodland edge
Some parts of the woodland are kept open and the flora in these areas resembles woodland glades and rides. Such habitats are considered within the woodland section of this report. Woodland:
The woodland on site is a fairly homogenous stand of mixed broadleaved tree species with rare coniferous trees. The canopy of the majority of the woodland on site was fairly closed except for the access roads and managed clearings. Woodland cover was an estimated at 80% for the whole site. Although topography changes from sloping to the west to flatter to the east, the woodland habitat type remained fairly uniform throughout with small areas of localised flushing. Frequent species in the canopy included Ash Fraxinus excelsior, Sycamore Acer pseudoplatanus, with occasional Wych Elm Ulmus glabra and rare Beech Fagus sylvatica. Some parts of the site included rare Scots Pine Pinus sylvestris, a species that often planted as plantation or specimen trees. The under-storey and scrub under the deciduous woodland areas was fairly open to the east of the site, becoming much more dense upslope in the west. Canopy cover was estimated at approximately 40% including Hazel Coryllus avellana, Elder Sambucus nigra, a maple acer sp., Red Currant Ribes rubum and bramble Rubus fruticosus agg.. Red Currant is considered to be a possible indicator of ancient woodland habitat. There was some evidence of Ash regeneration in the woodland, which should be encouraged, however there was also a large amount of invasive Sycamore regeneration. The woodland supported a excellent mixture of characteristic woodland ground-flora. Of the species recorded, thirteen are considered to be indicators of ancient woodland habitat. These indicator species are denoted in the following text with an asterisk. Native woodland species associated with the broad-leaved canopy included a polypody Polypody sp., (NT)1*Greater Butterfly-orchid Platanthera chlorantha, Common Spotted-orchid Dactylorhiza fuchsii, *Early-purple Orchid Orchis mascula, Enchanters-nightshade Circaea lutetiana, *Wood Anemone Anemone nemorosa, *Herb-Paris Paris quadrifolia, Wood Avens, Geum urbanum, *Common Dog-violet Viola riviana, *Solomons-seal Polygonatum multiflorum, *Bluebell Hyacinthoides non-scripta, *Wild Garlic Allium ursinum, *Dogs Mercury Mercurialis perenne and *Common Twayblade Listera ovata. In the more open areas of woodland which resembled glades and rides (Figure 2), the ground-flora also included Bracken Pteridium aquilinum, (NT) Wild Pansy Viola tricolor ssp. tricolor, Tall Fescue Festuca arundinacea, Bugle Ajuga reptans, Common Nettle Urtica dioica, Small Scabious Scabiosa columbaria and *Hairy St Johns-wort Hypericum hirsutum. Where wetter ground conditions prevailed alongside small streams on site, Square-stalked St Johns-wort Hypericum tetrapterum and *Remote Sedge Carex remota were also present. Also on site was the aggressive invasive species Himalayan Balsam Impatiens glandulifera that was becoming dominant in open parts of the site (Figure 3).
1 Near Threatened according to the Vascular Plant Red data List for GB (2005) edited by C.M. Cheffings &L. Farrel.
Figure 2 Woodland clearing on site.
Figure 3 Abundant Himalayan Balsam with Solomons-seal beneath
The woodland habitat included standing and fallen dead/decaying wood, frequently with standing pine stumps, in well lit situations favourable to decaying wood invertebrates (Figure 4).
Figure 4 Fallen dead wood
Other: In the south-west of the site there was a tufa spring running down the hill and eventually joining the network of canalised ditches on the site that associated with the on gunpowder work. The culverts of the gunpowder works are know dry for much of the year and exit in to the River Kent. The river itself borders the site and should be considered as a feature of considerable ecological consideration in its own right not the least due to its designation as a SSSI.
Grassland is extremely limited in extent on site owing to the largely wooded character of the site. Where found bordering the caravan pitches, grassland is floristically species-poor and, due to the intense mowing regime, has a low potential to support a wide range of fauna. The flora along the margin of the woodlands and in the open glade-like areas is diverse in comparison to mown sections of grassland surrounding the caravan pitches. The resultant sward has a more diverse structure creating more varied habitats for invertebrates, reptiles, birds and small mammals such voles and shrews. These habitat conditions also provided important resources for butterflies and
other nectaring invertebrate species such as hoverflies (Syrphidae) and bees (Apoidea). Woodlands on site exhibited the character of upland ashwood, a priority habitat in the UK BAP (www.ukbap.org.uk).The term upland ashwoods is used for woods on base-rich soils in the north and west of Britain, in most of which Ash is a major species. The term upland reflects the abundance of this type of woodland on base-rich soils in upland Britain, rather than the altitude at which individual woodlands occur. Upland ashwoods are found on base-rich soils throughout the uplands of north-west Britain and Northern Ireland. In Cumbria, upland Ash woodland is particularly concentrated on the limestones of Morecambe Bay (where it is locally extensive) and Orton Fells in the Cumbria Fells and Dales Natural Area. Woodland is an important feature of the limestone country around Morecambe Bay and the low fells to the north but much of the area further north and east is relatively sparsely wooded (www.english-nature.org.uk). The limestone woodlands mostly comprise Ash, Hazel and Small-leaved Lime along with Sessile Oak, Elm and lime-loving shrubs. Many of these shrubs are found here close to or at the northern limit of their distribution in Britain. They can support a rich ground flora such as those found on site. There are no precise data on the total extent of upland ashwoods in the UK, but the estimated total extent of ancient semi-natural woodland of this type is 40,000 to 50,000 ha (www.wildlifeincumbria.org.uk). Nationally, upland Ash woodland has declined in area through clearance, overgrazing and replanting with non-native species, by about 30-40% over the last 50 years. In Cumbria there are 15,593 ha of ancient semi-natural woodland 2, an unknown proportion of which is upland ashwood. On the Morecambe Bay limestone this proportion may be about 90%, but in the other areas it will be much lower. There are no precise data for loss...