Mammals including badger, otter, red squirrel, mink, fox, stoat, hedgehog and deer are a common sight. The Vartry Reservoirs are known for wintering waterfowl. Good numbers of duck can be seen in the winter with the most common being mallard, widgeon and teal. Other ducks such as pochard, tufted duck and goldeneye occur in smaller numbers. Waders like lapwing and curlew are commonly seen around the shores of the lake and on adjoining agricultural land. Mute and whooper swans also frequent the reservoirs during the winter. Other common species include little grebes, cormorants and grey herons. If you are lucky, you may spot kingfisher. During summer, keep an eye out for grey-crested grebes which breed on the lakes.
Many birds breed and nest in the uplands: red grouse, peregrine, merlin, skylark, meadow pipit, common snipe and whitechat. Common visitors are hen harrier, golden plover, wheatear and stonechat. Grey wagtail and dipper are commonly seen at upland streams.
Deer are a common site in the Wicklow Uplands. The species most commonly seen are Skia hybrid which is a cross between the native Irish Red Deer and the Japanese Sika Deer. Sika Deer are originally from Japan and they were introduced to Ireland by Lord Powerscourt in1859 at his estate neat Glencree, Co Wicklow. Unfortunately they escaped from captivity and in Wicklow interbred with the native Red Deer. The result is that now all the deer in Wicklow are hybrids, a mixture of Red and Sika Deer. In autumn, rutting Red stag road, the Sika stag whistles while the Sika hybrids can make a curious mixture of both sounds – sometimes starting with a whistle and ending in an attempted roar.