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Malham Tarn at Sunrise Copyright Dan Cook

Malham Tarn NNR – Conservation and Monitoring

Why monitor at Malham Tarn?

The National Trust’s National Nature Reserve at Malham Tarn is a very special place with an amazingly rare and dramatic array of plants and animals from the really unusual Tarn Fen (unique assemblage of fen plants and insects) to raised bog, orchid-rich wet flushes and limestone pavement and the tarn itself with crayfish, otters and many breeding birds. However there are a number of threats, including nutrient enrichment, erosion of the peat bog and from aerial depositions and climate change.

Aim of the work at Malham Tarn

The project is specifically addressing the concerns about nutrient enrichment from the catchment and atmosphere as well as the erosion of the peat bog. In addition, it is setting up long-term monitoring systems to ensure we can pick up trends and alter the management of the site if necessary.

Achievements at Malham Tarn

Work in recent years has greatly reduced nutrient (especially nitrogen and phosphorus) inputs to the Tarn and Fen and has restored the hydrology (water relations) of most of the raised bog by blocking old ditches and preventing damage from burning and grazing.

Who is involved in monitoring Malham Tarn?

The National Trust is working closely with many partners – including the Field Studies Council, the Yorkshire Dales National Park Authority, Natural England, University researchers, ecological contractors and many local volunteers.  The National Trust would welcome interest from new volunteers to help with biological recording and monitoring.