COUNTY: CUMBRIA SITE NAME: RIVER EDEN & TRIBUTARIES

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1 Date notified: 29 May 1997 File Ref NY52/5 COUNTY: CUMBRIA SITE NAME: RIVER EDEN & TRIBUTARIES Status: Site of Special Scientific Interest (SSSI) notified under Section 28 of the Wildlife and Countryside Act 1981, as amended. Local Planning Authorities: Eden District Council Carlisle City Council Lake District Special Planning Board Cumbria County Council National Grid Reference: NY Length of River SSSI: 410 km Ordnance Survey Sheets 1:50 000: 85,86,90,91,98 Date notified (under 1981 Act): 1997 Other information: Geological Conservation Review Sites at Stenkrith Beck, Hilton Beck and River Belah are being notified as part of this site. The site interest includes the following habitat and species listed in the EC Habitats and Species Directive (92/43/EEC): Floating vegetation of plain and sub-mountainous rivers - Annex I White-clawed crayfish Austropotamobius pallipes - Annex II, V Atlantic salmon Salmo salar - Annex II, V Brook lamprey Lampetra planeri - Annex II River lamprey Lampetra fluviatilis - Annex II, V Sea lamprey Petromyzon marinus - Annex II Bullhead Cottus gobio - Annex II Otter Lutra lutra - Annex II, IV White-clawed crayfish and otter are also protected under Schedule 5 of the Wildlife and Countryside Act 1981, as amended. Schelly Coregonus lavaretus is also protected under Schedule 5 of the same Act. This site overlaps with the following existing SSSIs: Spadeadam Mires, King Water, Irthing Gorge, Gelt Woods, Geltsdale and Glendue Fells, Janny Wood Section, Swindale Beck, Appleby Fells, Smardale Gill, Scandal Beck & Stone Gill.

2 Description and Reasons for Notification Key Features The Eden is an outstanding floristically rich, northern river on sandstone and hard limestone. The diversity of aquatic plants is amongst the highest of all rivers in Britain. The aquatic flora includes uncommon species and those at the geographical limit of their British distribution. Some of the headwaters of the Eden comprise one of the most important British sites for the native white-clawed crayfish. The river is also of high invertebrate interest for species associated with river shingles and sandbanks. The fish fauna includes Atlantic salmon, bullhead and all three species of lamprey found in British rivers. The Eden supports a high diversity of breeding birds associated with riparian habitats. The sand martins nesting in the river banks collectively comprise the largest colony in Cumbria. It is also of regional importance for wintering wildfowl and otters. Geology and Topography The catchment of the River Eden includes headwaters running off the Yorkshire Dales, the North Pennines and the eastern fells of the Lake District. The main stem of the Eden rises in the Yorkshire Dales, flowing over Carboniferous limestones, sandstones and mudstones. Downstream from Kirkby Stephen the gradient lessens and the Eden meanders over a broad valley of sandstones, mudstones and glacial deposits of alluvium and boulder clay. From Lazonby the river then flows through steep-sided sandstone gorges and valleys until it flows out onto the Carlisle floodplain. The catchment on the west side of the Eden arises from the Lake District fells. There are two major standing water bodies, Ullswater and the impounded Haweswater Reservoir. The presence of these water bodies, and the herringbone pattern of the catchment tributaries, means the River Eden has a fairly stable flow regime not given to sudden peaks in flow. Streams flowing into the main stem of the Eden from limestone are calcareous, whilst those flowing off the Pennines and the Lake District fells are more acidic. The nutrient status of the Eden also gradually changes along its length as nutrient loadings naturally increase in the lower reaches. Aquatic Flora The variations in the physical and chemical character of the Eden result in an unusual and exceptionally rich aquatic flora with 184 plant species recorded. Upstream from Appleby, the aquatic flora is typical of nutrient poor, rapid upland rivers. Bryophytes and algae are the main components with, for example, the liverworts Marsupella, Nardia, Scapania, Solenostema and a variety of filamentous green algae and diatoms. In the splash zone mosses are abundant, including Brachythecium spp, Racomitrium aciculare and Schistidium alpicola. Downstream from Kirkby Stephen the gradient lessens, the flow is less turbulent and the river is characterised by large gravel beds. The quieter areas between the gravel beds support the first flowering plants, with species such as alternate-leaved water milfoil Myriophyllum alterniflorum appearing in the river. Below Appleby, the middle reaches of the Eden support an aquatic flora characteristic of sandstone and limestone rivers. The Eden is particularly unusual in the number of nationally uncommon species it supports. In the slower flowing sections this includes curly pondweed Potamogeton crispus, perfoliate pondweed Potamogeton perfoliatus, and various-leaved pondweed Potamogeton gramineus. There are also three species towards their northwestern limit in Britain: flowering rush Butomus umbellatus, opposite-leaved

3 pondweed Groenlandia densa and horned pondweed Zannichellia palustris. Water crowfoots dominate the faster flowing reaches with the species Ranunculus fluitans, R. penicillatus, R. aquatifs and R. calcareous present. Among the bankside plants, whorlgrass Catabrosa aquatica, lesser water-parsnip Berula erecta and pink waterspeedwell Veronica anagallis-aquatica are the most notable. In the lower reaches the algae Hildenbrandia rivularis, Nostoc parmelioide and the lichen Collema fluviatile appear in the river. The uncommon hybrid pondweeds, Potamogeton x olivaceus and P. x cooperi are found towards Carlisle. Riparian habitats Throughout the River Eden there are stands of riparian alder or willow woodland associated with backwaters and seasonally flooded channels. The least undisturbed riparian habitats are found on the River Irthing where there are areas of alder swamp on gravel and shingle. The channel here is actively migrating and changes annually with the erosion and deposition of large gravel and shingle banks. These woodlands have an alder Alnus glutinosa canopy with a dense tall understorey dominated by nettles Urtica dioica with frequent butterbur Petasites hybridus, cleavers Galium aparine and hogweed Heracleum sphondylium. The wettest areas support small patches of greater tussock-sedge Carex paniculata. Floodplain alder woodland is widespread in Britain but examples are confined to undisturbed flood plains. Many of the remaining stands of floodplain woodland only occur as isolated, nutrient-enriched fragments. The stands on the Irthing are the largest known areas of this type in Cumbria. Swamp dominated by lesser pond-sedge Carex acutiformis, with bittersweet Solanum dulcamara, gypsywort Lycopus europaeus and water mint Mentha aquatica, is an integral component of the Irthing flood plain. This swamp occurs at the base of natural amphitheatres formed by previous meanders of the river. Lesser pond-sedge swamp has a limited national distribution with extensive stands largely restricted to the Fens, Broads and around the Cheshire meres. The Irthing sites are the most extensive in Cumbria. Where the River Eden meanders over floodplain there are fragments of old channels and ox-bow lakes. Very few of these important riparian habitats remain undisturbed from drainage or other land operations. The few remaining examples on the River Eden are important habitats for aquatic plants, for example, water plantain Alisma plantagoaquatica, branched and unbranched bur-reed Sparganium erectum and S. emersum and lesser water-parsnip. Invertebrates The headwaters of the River Eden comprise one of the most important remaining sites in Britain for the native white-clawed crayfish Austropotamobius pallipes, a species characteristic of calcareous streams with high water quality. Stream systems on the Eden which support native crayfish include the Lowther system, River Eamont, the Leith and Lyvennet, Hoff and Helm Becks, Briggle Beck, Scandal Beck and the River Belah. There are also crayfish in the main channel of the Eden between Temple Sowerby and Kirkby Stephen. The Eden is also of high invertebrate interest for species associated with river shingles and sandbanks. Of particular interest are the shore bug Sadula fucicola and the leaf beetle Hydrothassa hannoverianna, both of which are nationally rare. Six nationally scarce

4 species have also been recorded, including the ground beetles Bembidian schuepelli and B. fluviatile; found on sand by northern rivers, and Asaphidian pallipes. The flies Loncoptera meijeri, Camspicnemus marginatus and Rhaphium fractrum, found at the edge of the Eden, are also nationally scarce. Fish The fish fauna of the River Eden includes Atlantic salmon Salmo salar, bullhead Cottus gobio, sea lamprey Petromyzon marinus, river lamprey Lampetra fluviatilis and brook lamprey L. planeri. The principal salmon spawning and nursery grounds are found on the main river between Temple Sowerby and Kirkby Stephen, the Caldew, Irthing, Gelt, King Water, Eamont, Lowther, Scandal Beck and the Pennine becks: Briggle, Crowdundle, Milburn, Trout, Hilton and Belah. Bullhead have been recorded from most of the river reaches included in the SSSI, apart from the Irthing above St Mary's Vale and the Gelt above Gelt House. There are extensive sea lamprey spawning and nursery grounds on the main channel of the Eden from Carlisle upstream to Warwick Bridge, Wetheral and Armathwaite. Brook and river lampreys are widespread in the Eden catchment. The Eamont, Trout Beck, River Belah and Hilton Beck are particularly good. Ullswater at the head of the River Eamont supports a large population of schelly Coregonus lavaretus. This nationally rare fish is found in four lakes in the Lake District, of which - Ullswater is the largest. The other large lake in Cumbria known to support schelly, Haweswater, is impounded for water supply. The Ullswater system is also notable as a natural lake/stream system supporting salmon populations. Birds The River Eden supports a diverse assemblage of breeding bird species associated with rivers and adjacent wetland habitats. The breeding waders are particularly notable with redshank, curlew, oystercatcher, snipe and common sandpiper. There are also dipper, grey wagtail and kingfishers on the lower reaches. The Eden and its tributaries, especially the lower Eden, support high numbers of nesting sand martins. The natural sandy banks of the river act as one unit which collectively supports the largest number of breeding sand martins in Cumbria. The Eden valley also provides habitat for over 1% of the national population of wintering whooper swans. However, the main feeding grounds of the swans are on cropland and improved grassland areas which are outside the SSSI boundary. The swans congregate at two distinct sites in the middle reaches around Culgaith and Crosby-on-Eden further downstream. The middle reaches are also of regional importance for wintering wildfowl particularly surface feeding ducks and geese. Otters The River Eden system is of regional importance for otters Lutra lutra. The lower Eden, River Irthing and King Water are important strongholds for otters within the catchment. These river stretches have the best remaining areas of undisturbed riparian habitat and associated features favoured by otters. At the present time otters are slowly spreading into the middle and upper reaches of the catchment.

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