Rivers and streams
This encompasses any flowing water such as major rivers and their tributaries and coastal gills. Rivers and streams are dynamic systems, which exhibit a mosaic of features such as riffles, pools, shingle beds and sandbars that support a diverse range of plants, animals, fish and invertebrates.
There are few rivers which have not been physically altered by humans. Many larger water courses have been canalised or otherwise modified to reduce flood risk. These processes have resulted in degraded habitats supporting fewer species. This trend is now being reversed with opportunities to recreate naturally functioning systems being implemented. Watercourses also act as important corridors that link together other wildlife features and provide safe routes for species to move between sites.
The River Tees is the only major river in the Tees Valley. The water quality of the River Tees suffered in the 19th and 20th century from pollution associating with industrial and urban developments. Since the 1970’s, the water quality has improved, with salmon returning in recent years. Small becks, especially those tributaries in Middlesbrough, support thriving populations of water vole.
