Insularity effects on the assemblage of the blood parasite community of the birds from the Gulf of Guinea

Abstract

Aim Lower species diversity, increased population densities and ecological niche enlargement are common characteristics of island faunas. However it remains to be determined if they extend to the parasite community. We tested if Haemosporidia parasite pressure varies between islands and the mainland with two different levels of analysis: i) at the host community level, and ii) with paired-species comparisons between islands and the mainland. Location Gulf of Guinea, West Africa. Methods We used molecular-based methods to identify avian Haemosporidian parasites (Plasmodium, Haemoproteus and Leucocytozoon) to describe their diversity, prevalence, host specificity and their phylogenetic relationships in five islands of the Gulf of Guinea and in nearby mainland areas. Results We found reduced Haemosporidia diversity on islands for Haemoproteus and Leucocytozoon, but not for Plasmodium. In addition, lower parasite prevalence on islands was found using a paired-species approach. Although the mean host specificity of the parasite community on islands did not differ from the mainland, we found a very distinct parasite species assemblage on the islands, which was composed of both the most generalist and the most specialist lineages. Main conclusions This study supports the hypothesis that parasite pressure is reduced on islands. Colonization is made by generalists with high host switching capacities, with some subsequently evolving into highly specialised parasites. This suggests that ‘taxon cycle’ dynamics may explain the assemblage of insular parasite communities.

Spatiotemporal patterns of avian host–parasite interactions in the face of biogeographical range expansions

“…with SGS1 and LK06 lineages; Figure 4). Thus, infections in bird species with medium to high gene flow (migratory bird species) may have been acquired on the mainland, indicating that these species may act as transporters and reservoirs for haemosporidian lineages in the Canary Islands (Clark & Clegg, 2015; Loiseau et al., 2017; Padilla et al., 2017; Pérez‐Rodríguez et al., 2013).…”

“…The opposite trends of host–parasite networks between older and younger regions in New Guinea and the Canary Islands suggest that parasite communities may structure differently after colonizing new regions depending on dispersal barriers between regions (Clark & Clegg, 2015; Clark et al., 2014; Cornuault et al., 2012; Mata et al., 2015; Nieberding et al., 2006), and host specificity of haemosporidian lineages (Clark & Clegg, 2015; Clark et al., 2018; Loiseau et al., 2017). In the Canary Islands, the oceanic barrier between the archipelago and the mainland probably acts as a strong dispersal barrier, reducing dispersal of new lineages to the islands and thereby allowing for host niche expansion in the few lineages that manage to colonize the archipelago (Hoberg & Brooks, 2008; Nieberding et al., 2006; Pérez‐Rodríguez et al., 2013).…”

“…In the Canary Islands, the oceanic barrier between the archipelago and the mainland probably acts as a strong dispersal barrier, reducing dispersal of new lineages to the islands and thereby allowing for host niche expansion in the few lineages that manage to colonize the archipelago (Hoberg & Brooks, 2008; Nieberding et al., 2006; Pérez‐Rodríguez et al., 2013). Generalist parasites that migrate may also more successfully establish on islands compared to specialists (Clark & Clegg, 2015; Loiseau et al., 2017). According to our data and a previous study from Morocco (Mata et al., 2015), the most common and generalist parasite lineage in the Canary Islands ( Plasmodium lineage LK06) seems to be a specialist in mainland communities (Figures and ).…”

“…Our study presents evidence at the community level in favour of noninvasive birds experiencing low levels of haemosporidian infections following natural colonization of new areas, documenting how host–parasite networks and associations differ in distinct geographical settings. Such release from pathogens has been suggested as a mechanism to explain taxon cycles (the idea that species pass through phases of expansions and contractions) (Loiseau et al., 2017; Marzal et al., 2011; Ricklefs, 2011). One study on another host–parasite system has shown that hosts can escape from parasites by colonizing new areas and that after a lag‐time, parasites and vectors catch up with their hosts (Stone et al., 2012).…”

Malária aviária: desenvolvimento eritrocítico de parasitas através de infecção experimental, identificação e classificação de novas espécies de hemosporídeos

“…O presente estudo revelou uma grande diversidade de linhagens de hemosporídeos. Algumas das linhagens encontradas no presente trabalho foram previamente descritas em outros estudos e, na sua maioria na América do Sul [13][14][15]22,23,[76][77][78][81][82][83][84] [85][86][87][88] . Das linhagens encontradas no presente estudo nenhuma foi identificada ao nível da espécie, tendo-se limitado ao gênero.…”