River Ribble (Long Preston Deeps)

Also within

North Yorkshire County

Condition (Natural England)

Habitats

Fast flowing river and stream

Geology & landscape

Geological Feature: River Terrace · Geological Period: Carboniferous · Rock Type: Alluvium, Carboniferous Limestone, Glacial Till, Limestone, Millstone Grit

Landscape processes: Fluvial, Glacial

Birds & fish recorded

Birds

Fish

Description

Area, 168.8 hectares 417.12 Description The Long Preston Deeps section of the River Ribble is noted for its unusual physical nature in that it traverses a flat flood plain in the upper half of its catchment. This contrasts with most other river systems, where the flat meandering form only develops in the lower reaches. This unusual situation, combined with the base rich water and fine river deposits, results in the River Ribble supporting a unique aquatic flora, an assemblage found here at its upstream limit for an English river. In addition, the flood plain is an important breeding area for wading birds, including snipe s, redshank and lapwing. The river catchment is dominated by Carboniferous Limestone and the river is underlain by limestone with Millstone Grit at the northern end. The base rich character of the water is illustrated by the occurrence of spiked water milfoil Myriophyllum spicatum, brook water crowfoot Ranunculus penicillatus var. calcareus and blanket weed Cladophora glomerata. The fine material on the river bed is derived from alluvium and river terrace deposits and boulder clay from the valley bottom. Species characteristic of such fine sediment and slow flowing water include yellow water lily Nuphar lutea, perfoliate pondweed Potamogeton perfoliatus, curled pondweed Potamogeton crispus, broad leaved pondweed P. natans, lesser pondweed Potamogeton pusillus, water plantain Alisma plantago-aquatica and bulrush Schoenoplectus lacustris. Canadian pondweed Elodea canadensis and river water crowfoot Ranunculus fluitans are common on the faster flowing stretches. The site is also important for the presence of the nationally rare northern spike rush Eleocharis mamillata ssp. austriaca, which grows in flooded backwaters and shallows at the riverside. The upper River Ribble is of high water quality and is a healthy salmonid migratory river, salmon and sea trout pass through the Long Preston Deeps on their way up river to spawn and the river supports a good population of brown trout. The slow flowing waters are also used by a variety of coarse fish including grayling, chub, dace, pike, roach, lamprey, minnow, bullhead and stone loach. The piscifauna is, like the flora, very atypical for this area. The meandering structure of the river produces steep sandy cliffs on the eroding banks of the meanders and these provide nesting sites for kingfisher, sand martin and goosander. The rough marshy grassland adjacent to the river which undergoes periodic flooding forms an ideal nesting habitat for waders, in particular snipe, redshank and curlew, while other areas are used by oystercatchers and lapwing. In winter, the floodland is frequented by a variety of waterfowl and waders including whooper swan, pink footed goose, wigeon, teal, shoveler, tufted duck, water rail and dunlin. Other birds such as black-tailed godwit and ruff use the area on passage.

Species mentioned

Plant communities