A lack of hemosporidian parasites in some grassland songbirds reveals a research need in the Northern Great Plains

Abstract

We screened 103 Chestnut-collared Longspurs (Calcarius ornatus) and 69 Savannah Sparrows (Passerculus sandwichensis) captured in Alberta, Canada, for infections from 3 genera of hemosporidian parasites (Haemoproteus, Plasmodium, and Leucocytozoon). We used electrophoresis to visualize bands of PCR product to code for the presence of infections and found no instances of parasitemia among the individuals we tested. To confirm that our method of blood storage and processing did not impede our ability to detect infections that were present, we screened 22 Swamp Sparrows (Melospiza georgiana) in Manitoba, Canada, using the same methods, and detected 5 infections. No previous studies have documented a lack of blood parasites in grassland songbirds, but it is possible that this is a result of publication bias against null results. As climate change shifts vector ranges, naïve populations of grassland songbirds may suffer disproportionately if vector presence or parasite transmissibility is altered.