Hematozoa of passeriform birds from insular Newfoundland.

Abstract

A total of 2675 passeriform birds of 56 species were examined for blood parasites in insular Newfoundland during the period 1969–1972; 1872 (70%) harbored one or more species/genera of hematozoa. The genus Leucocytozoon, represented by L. dubreuili, L. fringillinarum, L. majoris, and L. sahkaroffi, occurred in 65% of the birds; and mixed infections involving these four species occurred commonly. Haemoproteids occurred in 22% of the sample, represented by Haemoproteus (Parahaemoproteus) fringillae, H. orizivora, and H. fallisi. Trypanosoma avium and T. calmettei occurred in 17.5% of the birds; members of the genus Plasmodium and microfilariae were uncommon. Prevalence of blood parasites in immature and adult birds was similar, and the prevalence was also similar in migratory and non-migratory species. The rate of parasite occurrence was remarkably similar from year to year in one area where the annual sample was large. Prevalence of parasites varied widely from locale to locale, and in some areas, low prevalence could be explained by absence of vectors.