Ecological and faunistic analysis of helminths in wetland birds of Baikal Siberia: 1. Anatidae

An ecological and faunistic analysis of helminths in the Anatidae of Baikal Siberia was carried out. We have established a systematic diversity of helminthofauna, which consists of 92 species from 4 classes. Cestodes and trematodes predominate in ducks and amounts to more than 80% of species composition of parasites. Nematodes and acanthocephalans make up less than 20%. The ratio of cestodes and trematodes is roughly the same, the last slightly dominate. The greatest diversity of parasite species was found in Anas (76 species), then in Netta (50), and Mergus (17). The total number of parasite species in Anas is 1.5 times greater than in Netta, 4.5 times - than in Mergus: a number of cestodes in Anas is 1.4 times greater than in Netta and 5.2 times - than in Mergus; a number of trematodes is 1.6 and 4.1 times greater than in Netta and Mergus respectively; a number of nematodes is 3.0 and 4.5 times greater. The number of acanthocephalans is small in all species of ducks - 1-3 species. Most species of helminths parasitize on one or two types of hosts, a little less - on 3-5. Certain types of worms can have maximum 8-9 hosts. It is established that the vast majority of helminths are specific for Anatidae. Some species of parasites are found in other Anseriformes - grebes, gulls, and common coots. The infection rate of ducks reaches 90% or more. It has been revealed that each group of Anatidae has a specific complex of parasites, although there are a number of worm species with a wide range of hosts, but they are relatively few. Also, each species of Anatidae inside subfamilies is infected with a specific complex of parasites. Therefore, the similarity coefficient of parasitophauna in different species of ducks turned out to be low. To a large extent the specificity of helminthofauna in ducks is determined by their habitual area and feeding habits.