The site includes two large pools, several ponds, rhynes, grazing marsh, hay meadows and hedgerows. It provides a habitat for a wide range of plants and animals. Great crested newts (Triturus cristatus), water voles (Arvicola amphibius), grass snakes (Natrix natrix) and brown hares (Lepus europaeus) have been seen and there is evidence that otters (Lutra lutra) are moving in. A wide variety of birds are making their homes on the site, including barn owls (Tyto alba), and it is visited by large number of migratory birds which use the Severn Estuary on their journeys. These include: curlew (Numenius arquatus), dunlin (Calidris alpina), redshank (Tringa totanus) and shelduck (Tadorna tadorna). The tidal range results in the estuary having one of the most extensive intertidal wildlife habitats in the UK, comprising mudflats, sandflats, rocky platforms and islands. These form a basis for plant and animal communities typical of extreme physical conditions of liquid mud and tide-swept sand and rock. The estuary is recognised as a wetland area of international importance and is designated as a Ramsar site. Parts of the estuary have also been designated a Site of Special Scientific Interest. The SSSI includes most of the foreshore upstream from Cardiff and Brean Down and most of the upper estuary as far as Sharpness. The Ashlands also provides a green link between the estuary and the Gordano Valley which has been designated as a national nature reserve.