Haemoproteus jenniae (Haemoproteidae, Haemosporida) infects gulls (Larus spp.) in South Africa, with redescription of Haemoproteus skuae.

Haemoproteus spp. are dipteran-borne protozoa that infect erythrocytes and reticulo-endothelial cells of birds. These parasites are not usually transmitted between birds belonging to different orders. The suborder Lari (order Charadriiformes) comprises ~170 avian species, the majority of which are aquatic, including gulls, terns, auklets, murres and skuas, among others. In spite of the diversity of this avian group, there is limited known diversity of haemosporidian parasites, with only 4 recorded Haemoproteus morphospecies thus far. We examined the blood smears of 21 kelp gulls (Larus dominicanus) captured at a breeding colony in South Africa, as well as Haemoproteus-positive archival blood smears of 15 kelp gulls and 1 Hartlaub's gull (Larus hartlaubii) sampled while under care at seabird rehabilitation facilities in South Africa. Haemoproteus sp. infection was detected in 19% of wild-caught kelp gulls. All parasites from the gulls were morphologically identified as Haemoproteus jenniae, a species previously recorded in Lari birds at the Galapagos Islands (Ecuador), Rocas Atoll (Brazil) and Poland. Gene sequencing uncovered a new cytochrome b lineage, LARDOM01, which was closely related to the previously reported H. jenniae lineage CREFUR01. Additionally, we evaluated a hapantotype blood smear of Haemoproteus skuae, which had been described infecting a brown skua (Catharacta antarctica) in South Africa. We provide a redescription of H. skuae and discuss the morphological characters distinguishing it from H. jenniae. Further research is necessary to improve our knowledge about the host and geographic distribution, health effects and phylogeny of H. jenniae and H. skuae.

Beta diversity, prevalence, and specificity of avian haemosporidian parasites throughout the annual cycle of Chilean Elaenia (Elaenia chilensis), a Neotropical austral migrant.

Migratory birds are implicated in dispersing haemosporidian parasites over great geographic distances. However, their role in sharing these vector-transmitted blood parasites with resident avian host species along their migration flyway is not well understood. We studied avian haemosporidian parasites in 10 localities where Chilean Elaenia, a long-distance Neotropical austral migrant species, spends part of its annual cycle to determine local parasite transmission among resident sympatric host species in the elaenia's distributional range across South America. We sampled 371 Chilean Elaenias and 1,818 birds representing 243 additional sympatric species from Brazilian wintering grounds to Argentinian breeding grounds. The 23 haemosporidian lineages found in Chilean Elaenias exhibited considerable variation in distribution, specialization, and turnover across the 10 avian communities in South America. Parasite lineage dissimilarity increased with geographic distance, and infection probability by Parahaemoproteus decreased in localities harbouring a more diverse haemosporidian fauna. Furthermore, blood smears from migrating Chilean Elaenias and local resident avian host species did not contain infective stages of Leucocytozoon, suggesting that transmission did not take place in the Brazilian stopover site. Our analyses confirm that this Neotropical austral migrant connects avian host communities and transports haemosporidian parasites along its distributional range in South America. However, the lack of transmissive stages at stopover site and the infrequent parasite lineage sharing between migratory host populations and residents at breeding and wintering grounds suggest that Chilean Elaenias do not play a significant role in dispersing haemosporidian parasites, nor do they influence local transmission across South America.

Loss of forest cover and host functional diversity increases prevalence of avian malaria parasites in the Atlantic Forest.

Host phylogenetic relatedness and ecological similarity are thought to contribute to parasite community assembly and infection rates. However, recent landscape level anthropogenic changes may disrupt host-parasite systems by impacting functional and phylogenetic diversity of host communities. We examined whether changes in host functional and phylogenetic diversity, forest cover, and minimum temperature influence the prevalence, diversity, and distributions of avian haemosporidian parasites (genera Haemoproteus and Plasmodium) across 18 avian communities in the Atlantic Forest. To explore spatial patterns in avian haemosporidian prevalence and taxonomic and phylogenetic diversity, we surveyed 2241 individuals belonging to 233 avian species across a deforestation gradient. Mean prevalence and parasite diversity varied considerably across avian communities and parasites responded differently to host attributes and anthropogenic changes. Avian malaria prevalence (termed herein as an infection caused by Plasmodium parasites) was higher in deforested sites, and both Plasmodium prevalence and taxonomic diversity were negatively related to host functional diversity. Increased diversity of avian hosts increased local taxonomic diversity of Plasmodium lineages but decreased phylogenetic diversity of this parasite genus. Temperature and host phylogenetic diversity did not influence prevalence and diversity of haemosporidian parasites. Variation in the diversity of avian host traits that promote parasite encounter and vector exposure (host functional diversity) partially explained the variation in avian malaria prevalence and diversity. Recent anthropogenic landscape transformation (reduced proportion of native forest cover) had a major influence on avian malaria occurrence across the Atlantic Forest. This suggests that, for Plasmodium, host phylogenetic diversity was not a biotic filter to parasite transmission as prevalence was largely explained by host ecological attributes and recent anthropogenic factors. Our results demonstrate that, similar to human malaria and other vector-transmitted pathogens, prevalence of avian malaria parasites will likely increase with deforestation.