The Border Rivers-Gwydir Catchment occupies an area of approximately 50,000 square kilometres.
The principal rivers that drain the inland slopes of the eastern highlands are the Dumaresq, Severn and Macintyre with the Gwydir River in the south west of the Catchment.
The Gwydir River is a major river of the Murray-Darling system that has undergone significant change with the construction of Copeton Dam in 1976. Much of the knowledge about fish and fish habitats of this system had not been recorded and as such current efforts by the Department to improve fishing in the river were hampered by the lack of baseline information.
A project was developed to document what fish and fish habitats were present before the dam was constructed in particular by gathering the oral histories of recreational fishers in the Gwydir catchment.
The key objectives of the project, which ran from November 2001 to April 2002, were to trial a method for documenting historical changes to fish and fish habitat within degraded rivers and to raise awareness of the natural resource management issues affecting native fish populations and the riverine ecosystem amongst the community.
A book Fish Everywhere - An oral history of fish and their habitats in the Gwydir River was the key output from the project. It summarises the views of residents on a variety of fish and fish related issues. It also presents up to date information on the biology of native fish and on the key issues such as cold-water pollution, fish passage, river regulation and riparian zone management.
This project was supported with a grant from the Natural Heritage Trust's Murray-Darling 2001 Fish Rehab Program.
Since its distribution in 2003 the book has proved to be a huge hit with recreational fishers and people who spend time on their rivers - not just in the Gwydir Valley.
The aquatic ecological community in the natural drainage system of the lowland catchment of the Darling River has been greatly modified since European settlement, through activities such as river regulation, the introduction of non-native species, agricultural practices and over-fishing. Many aquatic habitats are now degraded, and many native species have experienced declines in their numbers and distribution - some to the point where they are now listed as threatened.
This ecological community is listed as an endangered ecological community in NSW, meaning that it is likely to become extinct in nature in this state, unless the circumstances and factors threatening its survival and evolutionary development cease to operate.