Natural History of Upper Teesdale

7 - Fauna

Sheep, mostly Swaledale, are the most obvious mammals in Upper Teesdale and graze over much of the open upland areas. Many of the other mammals of the Upper Dale are inconspicuous or nocturnal, such as roe deer, badgers and hedgehogs. Smaller mammals such as voles and mice are abundant, and bats.

The Dale has a large number of bird species recorded, many breeding, but most leave the area in winter, the notable exceptions being the two grouse species. Woodlands at lower altitudes have the expected mixture ofsmall birds breeding, including the smallest British bird, the goldcrest which has a preference for conifer plantations.

Many of the interesting vertebrates living in Upper Teesdale are dependent on numerous invertebrates for food and many of these are abundant, with over 1,400 species recorded. The abundance of the invertebrates cannot be exaggerated and in simple terms for each sheep seen on the uplands in summer, there are tens times their weight of invertebrates hidden in the soils. Some of these invertebrates are extremely rare elsewhere in England and several have been described as species new to science.