A Definitive host is an organism that serves as a host during the maturity period of the parasite. This is also the host in which the parasite sexually reproduces (in the case of swimmer’s itch causing trematodes). Here the trematode transforms into an adult worm and lays eggs. These eggs are usually passed through the definitive host into the environment, usually through the faeces. The swimmer’s itch causing trematodes generally utilize waterfowl and other birds as their definitive hosts, often being ducks and geese. Some species will use small mammals that live in and around the water, such as muskrats and beavers.
We are actively seeking duck hunters in Alberta, interested in helping us examine birds for the presence of trematode worms. If you or anyone you know is a duck hunter and would be interested in participating in our study, please contact us.