Rainfall at African wintering grounds predicts age‐specific probability of haemosporidian infection in a migratory passerine bird

Abstract

In migratory species breeding in temperate zones and wintering in tropical areas, the prevalence of blood parasites may be affected by migratory strategies and winter habitat choice. We explored whether African winter habitat was linked to the probability of haemosporidian infection in the House Martin Delichon urbicum breeding in Spain, and tested for potential differences between age‐classes. As a proxy for winter habitat features, we analysed stable isotope (δ2H, δ13C and δ15N) values of winter‐grown feathers moulted in tropical Africa. Rainfall at the African winter grounds was related to the probability of being infected with haemosporidians and this effect differed among age‐classes. We found that haemosporidian prevalence was similar for young and experienced birds wintering in habitats of higher rainfall (2H‐depleted), whereas there were great differences in winter habitats of lower rainfall (2H‐enriched), with young having a much higher prevalence compared with experienced birds. Likewise, experienced birds wintering in habitats of higher rainfall had a higher probability of haemosporidian infection compared with experienced birds wintering in habitats of lower rainfall. By contrast, young birds wintering in habitats of lower rainfall had a higher probability of haemosporidian infection compared with young birds wintering in habitats of higher rainfall. These outcomes highlight the interaction of age with haemosporidian infection in the migratory ecology of the House Martin, which may drive carry‐over effects in this long‐distance aerial insectivore.

Influence of the haemosporidian Leucocytozoon spp. over reproductive output in a wild Neotropical passerine, the Thorn‐tailed Rayadito (Aphrastura spinicauda)

“…A similar result has been reported in an experimental study in Blue Tits (Podmokła et al 2014). Similarly, infected parents produced heavier Collared Flycatchers Ficedula albicollis nestlings (Kulma et al 2014), higher offspring survival of Hawaii Amakihis nestlings (Kilpatrick et al 2006), and higher provisioning rates (Richner et al 1995) Early life is an important period for the interactions with haemosporidian parasites (Valkiūnas 2005, Hammers et al 2016, Fletcher et al 2019, López-Calderón et al 2019. For example, most of the infections occur within the first year in Seychelles Warblers Acrocephalus sechellensis Hammers et al 2016) and in Collared Flycatchers.…”

“…There are some limitations to this study. Age is an important variable that affects exposure to parasites (Marzal et al 2016, Hammer et al 2016, López-Calderón et al 2019) and supports the terminal investment hypothesis. According to this hypothesis, infected individuals invest more in current reproduction if their prospects are compromised (Williams 1966).…”

The Impact of Avian Haemosporidian Infection on Feather Quality and Feather Growth Rate of Migratory Passerines

“…For example, it is known that populations of sand martins from western Europe (Great Britain, Spain, and Portugal) migrate to wintering areas with a sub-Saharan desert climate located in the Senegal River Delta [ 88 ], while house martin populations from southwest Spain winter in higher rainfall habitats such as the west African broadleaf forests [ 89 ], potentially exposing them to higher vector densities [ 90 ]. This, in turn, can increase their probability of acquiring haemosporidian infections [ 91 ]. Finally, the interplay between host immune defences and parasite exploitation strategies may further influence haemosporidian prevalence in bird communities [ 92 ].…”

Migration distance does not predict blood parasitism in a migratory songbird

“…If the costs of low‐intensity chronic malarial infection only become observable over an individual's lifetime (Asghar et al, ), then no relationship is expected between short‐term measures of individual condition (estimated from circulating corticosterone, scaled mass index, and feather quality) and malaria prevalence or intensity of infection (Schoenle et al, ; Sorensen et al, ). Understanding the factors that predict individual infection risk is an important component of effectively predicting the population dynamics of species, especially given that global change is rapidly affecting some of the mechanisms hypothesized to affect infection risk in migratory animals (Garamszegi, ; López‐Calderón et al, ).…”