Parasite island syndromes in the context of nidicolous ectoparasites: Fleas (Insecta: Siphonaptera) in wild passerine birds from Azores Archipelago.

Island syndrome, previously established for isolation process of insular vertebrates' populations, have been adapted to insular parasites communities, termed parasite island syndromes. In this work, were studied for the first time the insular syndromes for nidicolous ectoparasites of the bird species, Turdus merula, Sylvia atricapilla, Fringilla coelebs and Erithacus rubecula from Azores and the mainland Portugal. Flea species were only recorded on Azorean birds, namely Dasypsyllus gallinulae and Ctenocephalides felis felis, known as not host-specific parasites. In the absence of shared flea species between mainland and islands birds, a comparison among our fleas prevalence to Azores Islands and mainland fleas prevalence, recorded to others European studies, showed that Azorean host populations undergo higher prevalence than the mainland one. This result was consistent with parasite island syndromes predictions recorded to ectoparasites, hippoboscid flies and chewing lice, that fleas have higher prevalence on the Azores Islands compared to mainland Portugal. However, our results provide a new perspective to parasite island syndromes assumptions, namely in the context of nidicolous ectoparasites that spend only brief periods on the hosts' body.

Louse flies in Azorean and mainland populations of four Passeriformes species: A new perspective to parasite Island syndromes.

Hippoboscid flies, also known as louse flies, are obligate blood-feeders ectoparasites of birds and mammals. By studying louse fly parasites of four Passeriformes species, Eurasian blackbird (Turdus merula), Eurasian blackcap (Sylvia atricapilla), common chaffinch (Fringilla coelebs) and European robin (Erithacus rubecula), with dissimilar time of colonization of Azores islands, we tested whether: (i) island host populations have lower parasite richness than the mainland one; (ii) island host populations undergo higher parasite prevalence, mean intensities and mean abundance than the mainland one; (iii) island parasite diversity are composed exclusively by specific parasites and (iv) parasite richness is positively correlated with the island area and proximity to the continent. For these purposes, 775 birds were sampled for presence of louse flies, by modified fumigation chamber method, from Azores Islands (São Miguel, Terceira and Flores) and Portugal mainland. Insular and mainland parasite assemblages were statistically compared. We record for the first time to Azores, Ornithomya fringillina and Icosta minor from Portugal mainland. Louse flies had highest prevalence and abundance from Azores Islands compared to those observed in mainland birds, especially blackbirds. The insular parasite diversity of Azores blackbirds, blackcaps and chaffinches was richer than the one observed in mainland population. None of the hippoboscid flies observed on the islands and mainland were host-specific. Thus, our findings provide an upgrade of parasite island syndromes knowledge, in the context of the ectoparasites, namely to the hippoboscid flies case.

Unravelling population processes over the Late Pleistocene driving contemporary genetic divergence in Palearctic buzzards.

Population range expansions and contractions as a response to climate and habitat change throughout the Quaternary are known to have contributed to complex phylogenetic and population genetic events. Speciation patterns and processes in Palearctic buzzards (genus Buteo) are a long-standing example of morphological and genetic data incongruence, attributed to panmixia, habitat range shifts, contact zones, and climate change. Here we assess the systematics, phylogeography and population genetic structure of three nominal species of Palearctic buzzards, Buteo buteo (including B. b. vulpinus), B. rufinus (including B. r. cirtensis) and B. hemilasius. Phylogenetic analyses inferred from mitochondrial data recover B. hemilasius as sister to the sister clades B. r. rufinus and B. buteo complex (B. b. buteo, B. b. vulpinus, but also including B. r. cirtensis). In contrast, we find an unresolved genetic delimitation inferred from four nuclear loci, suggesting an ancestral genetic pool for all species. Time-trees suggest population contractions and expansions throughout the Pleistocene, which likely reflect habitat change and contrasting ecological niche requirements between species. Microsatellite-based extended Bayesian skyline plots reveal relatively constant population sizes for B. hemilasius, B. r. rufinus, and B. b. vulpinus, in contrast to a dramatic population expansion in B. r. cirtensis within the last 3 kya. Overall, our study illustrates how complex population processes over the Late Pleistocene have shaped the patterns of genetic divergence in Palearctic buzzards, due to the joint effects of shared ancestral polymorphisms, population expansions and contractions, with hybridization at contact zones leading to admixture and introgression.