Avian hematozoa from west-central Bolivia

A total of 641 birds representing 135 species of 25 families from Noel Kempff Mercado National Park in west-central Bolivia was examined for hematozoa; only 33 (5.1%) harbored blood parasites. Microfilariae were the most commonly encountered hematozoans, followed, in numerical sequence, by species of Haemoproteus and Plasmodium; Trypanosoma, Atoxoplasma, and Hepatozoon were seen infrequently. The survey included 13 new host-parasite records, and 58 species of birds were examined for blood parasites for the first time; 43 were parasite-free. The low prevalence of parasitism recorded in this survey is compared to other areas in the Neotropical region and to prevalence of blood parasites in the avifauna of other major land masses.     

Hematozoa from the spotted owl

One hundred five spotted owls (Strix occidentalis) from seven populations and three subspecies were examined for hematozoa. Haemoproteus noctuae, H. syrnii, Leucocytozoon ziemanni, Trypanosoma avium, Atoxoplasma sp. and unidentified microfilariae were recorded. All northern (S. occidentalis caurina), California (S. occidentalis occidentalis) and Mexican (S. occidentalis lucida) spotted owls were infected with at least one hematozoan; 79% had multiple infections. Twenty-two percent of the owls were infected with as many as four species of parasites. There were significant differences in the prevalence of these species of parasites occurring among the five populations of northern and California spotted owls sampled in California. Haemoproteus noctuae, H. syrnii and Atoxoplasma sp. represented new host records for this host species.     

Blood parasites of Nearctic-Neotropical migrant passerine birds during spring trans-Gulf migration: impact on host body condition

To test the hypothesis that migrants infected with blood parasites arrive on the northern coast of the Gulf of Mexico in poorer condition than uninfected birds, we examined 1705 migrant passerine birds representing 54 species of 11 families from 2 Gulf Coast sites for blood parasites. Three hundred and sixty (21.1%) were infected with 1 or more species of 4 genera of blood parasites. The prevalence of parasites was as follows: Haemoproteus spp. (11.7%), Plasmodium spp. (6.7%), Leucocytozoon spp. (1.3%), and Trypanosoma spp. (1.2%). Both prevalence and density of Haemoproteus spp. infection varied among species. We found no relationship of gender or age with the prevalence of Haemoproteus spp. infection or Plasmodium spp. infection, with the exception of the orchard oriole (Icterus spurius) for which older birds were more likely to be infected with Haemoproteus spp. than younger birds. We also found that scarlet tanagers and summer tanagers infected with species of Haemoproteus have lower fat scores than uninfected individuals and that rose-breasted grosbeaks and Baltimore orioles infected with Haemoproteus spp. have a smaller mean body mass than uninfected individuals. Blood parasites do seem to pose a physiological cost for Neotropical migrant passerines and may be important components of the ecology of these species.     

Hematozoa from Southern African vultures, with a description of Haemoproteus janovyi sp. n.

This study represents the first major survey of avian hematozoa from southern Africa and the only one dealing with blood parasites of vultures. Blood smears from 506 Rhodesian, Botswanan and South African vultures (Hooded, White-headed, Lappetfaced, Cape Griffon and Whitebacked Vultures) were examined for hematozoa. Haemoproteus janovyi sp. n. was observed in 35.2% of the vultures, Leucocytozoon toddi in 0.8%, Plasmodium fallax in 0.6%, Atoxoplasma sp. in 1.4% and microfilariae in 0.2%. Hematozoan prevalence increased with age of the vultures. Only 2 of 133 nestlings sampled during the dry season had patent parasitemias (L. toddi). Haemoproteid prevalence in immature vultures was depressed during the dry season, whereas it was stable throughout the year in adults. The only species which nests on cliffs (the Cape Griffon Vulture) did not harbor hematozoa whereas the other species which nest and roost in trees were infected with at least one hematozoan species.     

Paucity of hematozoa in Colombian birds

Sixty-four birds of 43 species were caught at six localities in Colombia during the dry season in March 1998 and investigated for hematozoa by microscopic examination of stained blood films. Haemoproteus coatneyi, Plasmodium vaughani, Leucocytozoon sp., and microfilariae were identified. The overall prevalence of infection was 8%. Prevalences of infection for Haemoproteus spp., Plasmodium spp., Leucocytozoon spp., and microfilariae were 3%, 2%, 2%, and 3%, respectively. All hemosporidian infections encountered were of low intensity (< 1% of infected erythrocytes). The low prevalences and intensities of hemosporidian parasites in this study are in accord with other records from the Neotropics.     

Blood parasites of some birds from Ghana

A total of 135 birds of 26 species in 13 families was examined for blood parasites; 43 birds (31.9%) of 13 species were infected; species of the Ploceidae were the most heavily infected. Species of Haemoproteus occurred most commonly 29 birds) while Leucocytozoon and Plasmodium species were virtually absent. There was no significant difference in the prevalence of hematozoa in birds from the mature rainforest and those in a savannah-urban setting.     

Avian hemosporidian parasites from northern California oak woodland and chaparral habitats

During spring-summer 2003-2004, the avian community was surveyed for hemosporidian parasites in an oak (Quercus spp.) and madrone (Arbutus spp.) woodland bordering grassland and chaparral habitats at a site in northern California, a geographic location and in habitat types not previously sampled for these parasites. Of 324 birds from 46 species (21 families) sampled (including four species not previously examined for hemosporidians), 126 (39%) were infected with parasites identified as species of one or more of the genera Plasmodium (3% of birds sampled), Haemoproteus (30%), and Leucocytozoon (11%). Species of parasite were identified by morphology in stained blood smears and were consistent with one species of Plasmodium, 11 species of Haemoproteus, and four species of Leucocytozoon. We document the presence of one of the parasite genera in seven new host species and discovered 12 new parasite species-host species associations. Hatching-year birds were found infected with parasites of all three genera. Prevalence of parasites for each genus differed significantly for the entire sample, and prevalence of parasites for the most common genus, Haemoproteus, differed significantly among bird families. Among families with substantial sample sizes, the Vireonidae (63%) and Emberizidae (70%) were most often infected with Haemoproteus spp. No evidence for parasite between-genus interaction, either positive or negative, was found. Overall prevalence of hemosporidians at the northern California sites and predominance of Haemoproteus spp. was similar to that reported in most other surveys for the USA, Canada, and the Caribbean islands.     

Prevalence of avian hematozoa in central Vermont

Peripheral blood smears from 1,547 birds, of 50 species, from 15 families trapped in Northfield, Vermont were examined for hematozoa. Numerous new host-parasite relationships were identified. The prevalence of all species of parasites over the 3 yr of the study was 42.5%. Prevalence of the genera of parasites were: Leucocytozoon--36.5%; Trypanosoma--7.3%; Haemoproteus--6.3%; microfilariae--1.0%; Plasmodium--1.0%. Peak prevalence (78.9%) occurred in the first half of July. Peak intensity was seen in the last half of June. Evidence from immature birds suggested that active transmission of all genera of hematozoans took place in the study area. Leucocytozoon gametocytes, unlike Haemoproteus gametocytes, were detected in smears from birds during all seasons of the year, and showed no period of complete remission. Trypanosoma and microfilariae also were seen throughout the year.     

A comparison of the blood parasites in three subspecies of the yellow wagtail Motacilla flava

One-hundred and eighty yellow wagtails Motacilla flava belonging to 3 subspecies (Motacilla flava feldegg, Motacilla flava flava, Motacilla flava thunbergi) were caught during the spring migration in south Kazakhstan and investigated by microscopic examination of stained blood smears. Haemoproteus anthi, Haemoproteus motacillae, Leucocytozoon fringillinarum, Leucocytozoon majoris, Plasmodium relictum, Plasmodium polare, Atoxoplasma sp., Trypanosoma sp., and microfilariae were identified. The overall prevalence of infection was 47.8%. Prevalences of Haemoproteus spp. (27.2%), Plasmodium spp. (25.0%), Leucocytozoon spp. (8.9%), Atoxoplasma spp. (4.4%), Trypanosoma spp. (1.1%), and microfilariae (0.6%) were recorded. No differences were discernible in parasite fauna or intensities of infection between males and females or between different subspecies. However, prevalence of infection of Haemoproteus, Leucocytozoon, and Plasmodium spp. was different in different host subspecies. These differences can be explained by differences in geographical location of breeding areas of these birds.     

Hematozoa in endemic subspecies of common kestrel in the Cape Verde Islands

We examined 130 Common Kestrel (Falco tinnunculus) representing two endemic subspecies and nine resident island populations on the Cape Verde archipelago between 1996 and 1999 to study diversity, prevalence, and intensity of hematozoa. Hematozoan diversity was very low; we detected only Plasmodium fallax, a species that is rarely found in Falconoformes, and, possibly, Haemoproteus brachiatus. Moreover, prevalence of Plasmodium fallax was low (1.5%) with a mean intensity of infection of 0.05 protozoa/10(-3) erythrocytes. Only one bird (0.8%) was infected with a gametocyte that was most likely Haemoproteus brachiatus; the intensity in this infected bird was 1.5 protozoa/10(-3) erythrocytes. A single parasite or two parasites were observed in blood smears in four additional birds, but identification to genus was not possible. This is the first record of blood parasites in birds on the Cape Verde Archipelago. The low prevalence of these parasites might be because of arid and less-favorable conditions for the pathogen's vectors. The sedentary nature and high level of isolation of the island kestrel populations are also factors that could decrease the probability of infection.