Blood parasites of trumpeter swans, Olor buccinator (Richardson), from Alberta

A total of 75 trumpeter swans (Olor buccinator (Richardson) from the Grande Prairie region of Alberta was examined for hematozoa; 26 (34.6%) swans were infected with Haemoproteus nettionis. A single infection of Leucocytozoon simondi and two of Plasmodium circumflexum also were recorded. Local, second year (SY) and adult (AHY) female swans had closely similar rates of hematozoan infection; the SY and AHY male swans had substantially higher infection rates than other subgroups.