among the scarcer mammals found on the reserve, and otters have returned to the now-clean rivers. Other mammal species targeted for monitoring during the creation process include the brown hare and the pipistrelle. The alder leaf beetle, formerly believed extinct in the UK, has colonised the Dearne and other local river catchments, probably introduced when the pollution-tolerant Italian alder was planted on restored land. Other uncommon insects found at Old Moor include the great silver water beetle, the longhorn beetle Pyrrhidium sanguineum, the dingy skipper butterfly, and a day-flying moth, the six-belted clearwing. Nationally scarce nocturnal moths include the cream-bordered green pea and chocolate-tip, while the red-eyed damselfly and red-veined and black darters are notable among the Odonata. Several rare flies have been recorded, including three species, Parochthiphila coronata, Calamoncosis aspistylina and Neoascia interrupta, otherwise known in the UK only from a few sites in the East Anglian fenland. An unusual plant gall found on creeping bent was caused by the nematode Subanguina graminophila. Scarce plants include yellow vetchling and hairy bird's-foot trefoil. Marsh orchids flower in grassy areas in the summer, and the same species, along with the bee orchid, has colonised the verges of the adjacent Manvers Way. Other scarce plants found in the area include hairlike pondweed, pond water-crowfoot and greater pond sedge. Threats and opportunities The Dearne Valley is a natural washland with a capacity of , and as such it can normally absorb overflow from its river. The floods of 2007 overwhelmed the storage capacity and covered the whole of Old Moor to hide-roof level, only the visitor centre being untouched. In the longer term, the reserve might be adversely affected by climate change, perhaps leading to alterations in the populations of woodland species. More positive effects may arise as the local environment improves, with habitat creation occurring beyond the reserve and better accessibility. A survey by the DVLP showed that 44% of respondents said that they liked to visit the local wildlife reserves, with another 17% mentioning waterways and lakes. When asked what they liked about the Dearne Valley area, 35% of replies said nature and wildlife. The success of Old Moor has led to the creation of similar RSPB reserves close to urban areas at Rainham Marshes east of London, Newport Wetlands in South Wales, and RSPB Saltholme on Teesside. References Cited texts External links Official site Constructed wetlands Old Moor RSPB visitor