Haemosporidian taxonomic composition, network centrality and partner fidelity between resident and migratory avian hosts.

Migration can modify interaction dynamics between parasites and their hosts with migrant hosts able to disperse parasites and impact local community transmission. Thus, studying the relationships among migratory hosts and their parasites is fundamental to elucidate how migration shapes host-parasite interactions. Avian haemosporidians are some of the most prevalent and diverse group of wildlife parasites and are also widely studied as models in ecological and evolutionary research. Here, we contrast partner fidelity, network centrality and parasite taxonomic composition among resident and non-resident avian hosts using presence/absence data on haemosporidians parasitic in South American birds as study model. We ran multilevel Bayesian models to assess the role of migration in determining partner fidelity (i.e., normalized degree) and centrality (i.e., weighted closeness) in host-parasite networks of avian hosts and their respective haemosporidian parasites. In addition, to evaluate parasite taxonomic composition, we performed permutational multivariate analyses of variance to quantify dissimilarity in haemosporidian lineages infecting different host migratory categories. We observed similar partner fidelity and parasite taxonomic composition among resident and migratory hosts. Conversely, we demonstrate that migratory hosts play a more central role in host-parasite networks than residents. However, when evaluating partially and fully migratory hosts separately, we observed that only partially migratory species presented higher network centrality when compared to resident birds. Therefore, migration does not lead to differences in both partner fidelity and parasite taxonomic composition. However, migratory behavior is positively associated with network centrality, indicating migratory hosts play more important roles in shaping host-parasite interactions and influence local transmission.