Rabbit Oryctolagus cuniculus
Rabbits are not native to Jersey. Introduced in the 12th or 13th Century this abundant mammal would probably be considered an invasive pest species if it had not had such an influence on the Island’s habitats that it’s removal now would lead to dramatic changes in the local environment. Originally brought from southern Europe as a food animal, rabbits inevitably escaped and quickly spread. Widespread in Jersey today, rabbits are particularly common on the coast where their grazing has long influenced the scenery. With the reduction in coastal sheep farming since the 19th Century, rabbits have become the major grazer of many coastland sites creating habitat essential for many plant and animal species we see today. Rabbits in Jersey until recently had few natural predators following the extinction of the stoat Mustela erminea; however, the recent colonisation by marsh harrier Circus aeruginosus and common buzzard Buteo buteo will give them something to think about. Jersey’s rabbits are susceptible to diseases within their population such as myxomatosis which often kill off many members of a localised population. Affected populations quickly recover.
Bank Vole Myodes glareolus
Bank voles are found throughout Britain but only on a small number of islands: distinct races occur on Skomer, Mull and on Jersey where M. glareolus caesarius is the Island’s only vole species. Bank voles are widespread in Jersey and, living underground in burrows, they are most often found in woodland and hedgerows but also rough coastal grassland and gorse preferring a lot of ground cover. Bank voles may be active in daylight and can often be watched by a quiet observer while out foraging . This species is very common and can be encountered all along the Island’s coastlands.
Millet’s Shrew Sorex coronatus and Lesser White-toothed Shrew Crocidura suaveolens
Shrew distribution in the Channel Islands is very interesting. Only Jersey has Millet’s or crowned shrew (formerly identified as common shrew S. araneus) and only Jersey and Sark have lesser white-tootheds (Guernsey, Herm and Alderney have white-toothed shrew C. russula). Millet’s shrews are often considered to live inland and lesser white-tootheds to be coastal, even feeding on the beach: however, this is a bit of a generalisation and our coastlands may often hold both species often alongside each other. These tiny, often inconspicuous mammals are very active insectivorous foragers and, with patience, can be watched amongst the rocks or in the vegetation. Shrews undoubtedly make up a significant part of the diet of the common kestrels Falco tinnunculus that are seen along the north coast.
Over the centuries no doubt many mammals previously found along Jersey’s coastlands have died out. Some, however, may be worthy of note:
Stoat Mustela erminea
The carnivorous stoat is native to Jersey but, once considered common and even a pest, there have not been any seen on the Island for more than 15 years. Formerly widespread, stoats became almost restricted to the coasts where they hunted over the wilder cliff lands and on the north coast even feeding among the boulders on the beach. While attempts at eradication in previous centuries may have had little long-term impact on stoat numbers they declined steadily during the 20th Century. Final extinction may have come following the introduction into the Island of the larger and more aggressive ferret Mustela putorius furo. While extinction seems likely, it is always worth looking out for the possibility that some animals survive on the coast somewhere.
Black rat Rattus rattus
Although the ubiquitous, introduced, brown rat R. norvegicus is widespread and abundant in Jersey today it was not the first rat species introduced onto the Island. Black, or ship rat, possibly arrived here in the 14th Century. This rat, much unloved by bird conservationists worldwide, is an able tree climber and thrives on beaches and among coastal boulders. The black rat, once the carrier of bubonic plague that ravaged Europe, seems to have become extinct in Jersey before the end of the 19th Century. Black rat declines in many parts of Europe have been attributed to the arrival of the brown rat which probably reached Jersey in the 18th Century: it must be assumed that this species’ arrival sealed the fate of the former. Interestingly, black rats survive still in Sark.
Several thousand years ago there were many, very different mammals found on Jersey. The excavations at La Cotte de St Brelade are particularly famous for the remarkable number of remains of large mammals found in the caves. Neanderthals living in the area had butchered many animals although the method of hunting is unclear: it has long been held that many, especially woolly mammoth Mammuthus primigenius, were driven over the high cliffs to their death. This fate of the butchered animals has not in fact been confirmed. Other species found in the caves include woolly rhinoceros Coelodonta antiquitatis, cave bear Ursus spelaeus and wild horse Equus ferus. Dwarf red deer Cervus elaphus found in caves at Belle Hougue on the north coast of Jersey were described as a distinct sub-species C. elaphus jerseyensis in 1940.