The raccoon Procyon lotor has been naturalised in Germany since 1927. The most dense populations exist in the states Hessia, Northrhine-Westphalia and Lower Saxony followed by Bavaria, Thuringia, Brandenburg and Mecklenburg-Vorpommern. By 1985, the raccoon had crossed the borders to Germany's neighbouring countries with the exception of the Danish and Polish borders. The factors limiting population growth are the numbers of suitable resting and breeding places - for which raccoons prefer oaks and beeches - and food supply. The raccoon has not been shown to negatively affect any indigenous wildlife species. In Hessia, plant matter, invertebrates and vertebrates each make up about one third of the diet of the raccoon. Mammals, birds, reptiles, amphibians and fish are important in winter and spring. Invertebrates can be found in considerable amounts all year long, with the maximum percentages found in summer. Plants are the main source of food in autumn. The raccoon has not yet become a problematic species, not even in urban areas. However, cases of rabies in raccoons in Germany have been documented, although seldom compared to fox Vulpes vulpes, marten Martes spp. and deer, e.g Cervus elaphus, Capreolus capreolus and Dama dama. Raccoons are also known as carriers of infectious diseases such as canine distemper, panleucopenia, Aujeszky's disease, canine parvovirus and canine adenovirus. The first case of human infection by a parasite, the ascarid Baylisascaris procyonis, from a pet raccoon was reported in 1991. The extermination of the raccoon population is not considered to be feasible. The yearly hunting bag of raccoons in Germany comprises 2,000–3,000 individuals.