[3] Adult flukes vary in host range and morphology dependent on the geographical location.
[4] Research on the life history traits of the parasites have been performed with hamsters and frogs as model species.
[5] While hamsters are not an ideal host, the parasite still infects them and deposits brown eggs in the intestines.
[5] Biologists began looking at the different life cycle stages involved in Metagonimoides oregonensis in the wild compared to the parasite in captivity.
In the western United States the primary host are mainly raccoons (Procyon lotor) with the possibility of minks (Neovison vison) as well.
Prosobranch snails which are found in rivers and streams are then infected with miracidia from the fecal matter from the primary hosts.
Considering in different parts of the country there are different species, the parasites naturally have to adapt to different hosts in order to survive.
[9] While in the eastern part of the United States another species of fresh water snails (Pleurocera goniobasis) has been found to be the first intermediate host for Metagonimoides oregonensis.
[2] Furthermore, studies have shown that the parasite can display life cycle variations also on a smaller scale, as for instance seen in different parts of Oregon.
[2] These salamanders are found mainly in streams and small rivers, and rarely seen out of the water, which could explain why they are such a popular host for the free swimming cercariae.