The coastline of Yell includes numerous Voes where Otters and various seabirds are common. Brown trout can be found in the inland waters.
Mammals
Yell claims to be the "Otter Capital of Britain". The shore is low-lying and the peaty soil is soft, making it ideal for excavation burrows. The long days in summer also make spotting these largely nocturnal creatures in daylight more likely than on the British mainland. Hugh Miles' documentary The Track of the Wild Otter was shot on location at Burra Ness at the mouth of Busta Voe; it gained awards and was produced for the BBC. Grey and Common Seals are also regular visitors to Yell's coast. Yell occasionally receives the odd Arctic visitor besides the tern; in 1977, a stray Bearded Seal was recorded. Normally these creatures only live on the pack ice. The island has its own subspecies of field mouse, as do some of the other Shetland Islands.
Birds
A population of Arctic Terns, known locally as Tirricks, migrates to Shetland from Antarctica during the summer. As swallows are sometimes seen as harbringers of summer elsewhere, in Yell and Shetland, it is the tirricks or terns that fulfil this role. Other birds that regularly visit Yell include Great & Arctic Skuas, various terns, Eider, Whimbrel, Red-throated Diver, Dunlin, Golden Plover, Twite, Lapwing and Merlin Falcons. The Eigg, and Ern Stack in the north west of Yell, is the last known nesting site of Shetlandic Sea Eagles, which were recorded there in 1910.
Flora
Yell has many of the usual plants found in northern European moorland, especially heather in abundance, including two carnivorous plants, the butterwort and the sundew. The gorges in the island, such as the Daal of Lumbister provide an important environment for some of the few trees on the island, since they are untouched by sheep grazing. Before human colonisation, it appears that Yell was wooded to some degree, at least with dwarf trees and shrubs. In the gorge at the head of Gloup Voe, Dog Roses and Honeysuckle can be found. As the peat preserves old plants and pollen to some degree, due to its anaerobic nature, it is possible to get some sense of the former vegetation of the island. For example, it is known that 40,000 years ago, before the advent of the last Ice Age, and probably any human habitation, that Oak, Scots Pine and Mediterranean heathers were growing here. The remains of these plants have been preserved in layers of ancient peat, which were in turn buried by the boulder clay left by glacial moraines.
Places to Visit on Yell