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.