The De Lank River features some of the most pristine habitats in Cornwall with outstanding water quality and a wealth of wildlife.
Mining
A walk along the De Lank River still reveals the remains of old tin mining streamworks. These can be found along much of its entire moorland length originally worked for tin lodes contained in its bed, banks and silts.
Freshwater Fisheries
Thousands of tonnes of granite from De Lank Quarry now occupying the rivers ancient channel prevent the free passage of migratory salmon and sea trout to the upper reaches of the De Lank River and prevent utilisation of a large area of potential spawning grounds in the rivers upper reaches. This has meant that the resident trout population in the river above the quarry obstruction is quite isolated. It is probable that these trout now represent a unique genetic type peculiar to the river.
In 1998 the fresh carcass of a very large Brown Trout was found between Delphi and Bradford Bridges. Retrieved for post-mortem this fish was found to be a hen (female) of over 3 pounds in weight aged about 10 years old. These extraordinary fish are not common but neither are they exceptional.
Impact of Recreational Activities
Members of the public sometimes construct small dams on part of the De Lank during the summer months, where easily accessible parts of the river are popular with tourists. The removal of the larger stones from the riverbed deprives plants and animals of a micro-habitat. The use of turf exacerbates the erosion of the riverbank and contributes towards the siltation of the substrate. This seemingly innocent recreation could damage stretches of one of Cornwall’s most pristine river habitats.
Conservation – Wildlife
The proposed Camel SAC will include the De Lank River. The proposed SSSI includes the De Lank River which has been identified as an outstanding example its type.
The De Lank is noted for its diverse and abundant flora and fauna. The invertebrate fauna is species rich, particularly in caddis. Nationally scarce species include the water beetle and the meniscus midge. Also of great importance are the many rare macrophytes present in the river and there is a noteworthy abundance and diversity of mosses and liverworts.
The European Otter ~ Lutra lutra
The River Camel and De Lank are an important stronghold for the otter one of Britain’s rarest and shyest mammals. Otters are regularly seen and travel the whole length of the river in their search for food, eels being their favourite prey. ‘Tarka’ the name given by Henry Williamson to the otter in his book of the same name means little wanderer. Indeed otters may travel 20 kilometres or more in a night. To cross from the North coast to the South coast otters will often use the river De Lank moving upriver until they find themselves at the source near the moors highest point at Brown Willy. From here it is a matter of crossing a couple of treacherous peat bogs and a short piece of open moorland of a few hundred metres taking them over the hill into the next catchment the source of the River Fowey.