Special Sub-Topic: Introduced Mammals of the United Kingdom Click Here To Play: Introduced Mammals of the United Kingdom

The UK has two native deer species, the red deer and the roe deer, and four introduced species. One of these four others was thought to have been introduced by the Normans, but it is now known that they were present in England in the first century A.D. and so must have been brought here by the Romans. Which deer is this?

Fallow deer. Sika deer were introduced to the UK in 1860, and have established themselves throughout the country. The muntjac was introduced to Bedforshire in the 1900’s, and has escaped and spread throughout England. The Chinese water deer was first brought to England in the 1870’s, and some of these were transferred to Woburn Abbey in Bedfordshire. Some of these deer escaped and formed the introduced population that exists today.

When the Normans invaded England they introduced one animal that remains a familiar sight in the present day. What is it?

Rabbit. The rabbit is native to Spain and Portugal, and was only introduced to England in the 12th century. The rabbit has also been introduced to Australia with devastating effects on indigenous (an organism which is native to a given region or ecosystem) wildlife.

One of the more interesting introduced mammals of the UK is native to Australia. What is it?

Red-necked wallaby. The red-necked wallaby can be found on the island of Inchconnachan, which is situated in Loch Lomond in Scotland. There are also small populations in Cumbria and elsewhere, though these are sighted only occasionally.

This animal was farmed in the 1920’s for fur, but after escapes occurred there is now a wild population covering almost the entire of the UK. What is it?

American mink. At present trappers are working to eradicate mink from Scottish islands, and it is possible that within a few years a program will start that will attempt to eradicate all the mink in the UK. Mink have caused water voles and sea birds to become increasingly rare.

An area in Scotland is home to an introduced population of small mammals, thought to have been brought there by Neolithic farmers. What is it called?

Orkney vole. The Orkney vole is a subspecies of the common vole, which is found on mainland Europe, but is absent from the rest of the UK. The Orkney voles are thought to have been introduced around 5000 years ago.

In 1902 some rodents escaped from a private collection in Hertfordshire, and there is now a wild population numbering some 10,000 individuals. What animal is it?

Edible dormouse. The edible dormouse obtained its name as the Romans used to keep them in large pots in order to consume them. Edible dormice are still eaten in the Republic of Slovenia where they are considered a delicacy.

Which American rodent was introduced to the UK in the 1800’s, and caused the widespread decline of a similar red species?

Eastern gray squirrel. The Eastern gray squirrel, known just as the grey squirrel in the UK, was introduced to the UK in the 1800’s, notably a pair were released in Cheshire in 1876. The grey squirrel has displaced the red squirrel across most of its former range, and now red squirrels are only found in reasonable numbers on the Isle of Wight and Scotland.

This very common mammal actually only arrived in Europe in the Middle Ages, and its earliest record in the UK is 1730. This rodent was also unknown in America until around 1750. What is it?

Brown rat. The scientific name of the brown rat is Rattus norvegicus, which means Norwegian rat. This name was given as it was thought that the rats had arrived in England by stowing away on ships from Norway; this, however, was incorrect and this misconception probably arose because of the similar lemming found in Norway. The brown rat actually originally came from Asia.

This burrowing rodent has escaped from captivity and formed a feral colony in Northern Ireland. What is it?

Black-tailed prairie dog. The black-tailed prairie dog is native to the Great Plains in North America, and the most common species kept in captivity. There is a population of escaped prairie dogs that live around Belfast Zoo, and other small populations further afield.

Keeping with Ireland, what small mammal species found in Europe and Africa was in 2008 found to have been introduced to Ireland?

Greater white-toothed shrew. The three other shrews mentioned are actual species of shrew that are found around the world. Interestingly, though they look like it, shrews are not rodents; instead they are in the order ‘Soricomorpha’. The greater white-toothed shrew was first identified in Ireland during examination of owl pellets, and since then seven have been trapped alive around Tipperary, Ireland.