Introduced protozoans:
| Protozoans | Acineta nitocrae | a suctorian ciliate |
| Protozoans | Glugea hertwigi | a microsporidian parasite |
| Protozoans | Heterosporis | Microsporidian |
| Protozoans | Myxobolus cerebralis | myxosporean parasite, salmonid whirling disease |
| Protozoans | Psammonobiotus communis | Testate amoeba |
| Protozoans | Psammonobiotus dziwnowi | Testate amoeba |
| Protozoans | Psammonobiotus linearis | Testate amoeba |
| Protozoans | Sphaeromyxa sevastopoli | Mixosporidian |
| Protozoans | Trypanosoma acerinae | a flagellate |