Lutra 55(2)_Mulder_2012

A review of the ecology of the raccoon dog (Nyctereutes procyonoides) in Europe

The raccoon dog (Nyctereutes procyonoides) was introduced from East Asia into the former USSR between 1928 and 1957. Since then it has colonised a large part of Europe and is considered an invasive alien species. This paper reviews the current knowledge on the ecology of the raccoon dog in Europe, undertaken as a basis for a risk assessment. The raccoon dog is about the size of a red fox (Vulpes vulpes). In autumn it accumulates fat and, in areas with cold winters, it may stay underground for weeks. It does not dig and often uses badger (Meles meles) setts and fox earths for reproduction. Raccoon dogs are monogamous. Each pair occupies a fixed home range the periphery of which often overlaps with that of neighbours. Pre-breeding population density usually is between 0.5 and 1.0 adults/km2. Habitat use is characterised by a preference for shores, wet habitats and deciduous forests. Foraging raccoon dogs move quite slowly, mostly staying in cover. They are omnivorous gatherers rather than hunters. Their diet is variable, with amphibians, small mammals, carrion, maize and fruits being important components. There is no proof of a negative effect on their prey populations. Raccoon dogs produce a relatively large litter of usually 6 to 9 cubs. After six weeks the den is left and the whole family roams around. From July onwards the cubs, still only half grown, start to disperse. Most cubs stay within 5 to 30 km of their place of birth, but occasionally travel more than 100 km.