industries. The name Old Moor may derive from an archaic meaning of moor, referring to a marshy area that was more difficult to cultivate than the alluvium of the flood plain. It had been enclosed as a farm by 1757, when it was owned by the Marquess of Rockingham. History The Dearne Valley was formerly a major coal mining area, with several accessible seams of high-quality coal, and in 1950s more than 32,000 colliers worked in its 30 pits. The coal industry dominated the area, and its waste rendered the River Dearne lifeless, although a few isolated wetland areas remained, monitored by local birdwatchers. The miners' strike of 1984 was the first sign of a national programme of pit closures in the UK that led to all the Dearne Valley mines being closed by 1993, with the loss of 11,000 jobs in the industry. About of the former Wath Manvers Colliery, including a coking plant and marshalling yard, was left as the largest derelict site in western Europe. The ground was heavily polluted and needed to be restored by covering it with clean soil deep enough for trees and scrubs to become established. To achieve this, of material was removed from the adjacent Old Moor, thereby creating a new wetland at that site. The Wildfowl & Wetlands Trust (WWT) were originally intended to run the proposed reserve, and planned a large lake for wintering wildfowl. The Royal Society for the Protection of Birds (RSPB) suggested adding reed beds to help the then-struggling bittern population; only 11 males were present in the UK at one point in the 1990s. The WWT was at that time also working on its London Wetland Centre, and pulled out of the Old Moor project since it lacked the resources to cope with two large projects. The creation of the reserve fell to Barnsley Metropolitan Borough Council, which offered the site to the RSPB in 1997. At that time, the bird charity was more interested in preserving established habitats than creating new sites, and declined to take on Old Moor. The reserve eventually opened in 1998 as part of the regeneration of the Dearne Valley, and was then developed further with the help of a lottery grant of nearly £800,000 in 2002. By 2000, the reserve had only 10,000 visitors annually, and was making a financial loss before being taken over by the RSPB in 2003.