Helminth parasites of the common eider duck (Somateria mollisima L.) in Newfoundland and Labrador

A total of 110 common eider ducks from six localities in Newfoundland and Labrador were examined for parasites. Twenty-seven species of parasites were recovered, eight being new host records and eighteen new host records for the common eider in North America. Ninety-five percent of the ducks were infected. -- The percentage of infection, range of numbers, and mean number of parasites is given for each age group and each sex of bird examined. Parasite species are discussed individually with regard to topics such as location within the host, other host records, the authority used in specific determination, minor variations, if any, from the original description, and comparison of results obtained by other authors who recorded the same species from common eiders. -- Two species of parasites were observed to cause damage to the host but none were lethal