Observations on malaria in European perching birds (passeriformes).

893 passeriformes birds belonging to 44 species and 14 families were investigated for blood parasites during a study running over 5 years. More than 1700 blood samples were taken. An average of 14% of the birds proved to be infected, most frequently with Leucozytozoon and Haemoproteus ( Parahaemoproteus ). Plasmodium sp. as well as other blood parasites were rarely found. Positive findings were correlated to the number of birds investigated per species, to the frequency and mode of inspections, the species of birds, the age of birds, and to the season. The latter is especially important for Haemoproteidaes . The distribution of exoerythrocytic schizonts in various organs is dealth with. The malaria infections only very rarely were fatal to the birds.