Migration strategy and pathogen risk: non-breeding distribution drives malaria prevalence in migratory waders

Pathogen exposure has been suggested as one of the factors shaping the myriad of migration strategies observed in nature. Two hypotheses relate migration strategies to pathogen infection: the ‘avoiding the tropics hypothesis’ predicts that pathogen prevalence and transmission increase with decreasing non-breeding (wintering) latitude, while the “habitat selection hypothesis” predicts lower pathogen prevalence in marine than in freshwater habitats. We tested these scarcely investigated hypotheses by screening wintering and resident wading shorebirds (Charadriiformes) for avian malaria blood parasites (Plasmodium and Haemoproteus spp.) along a latitudinal gradient in Australia. We sequenced infections to determine if wintering migrants share malaria parasites with local shorebird residents, and we combined prevalence results with published data in a global comparative analysis. Avian malaria prevalence in Australian waders was 3.56% and some parasite lineages were shared between wintering...

病原体暴露被认为是塑造自然界中纷繁多样迁徙策略的核心影响因素之一。现有两类假说将迁徙策略与病原体感染相关联：避热带假说（avoiding the tropics hypothesis）提出，病原体流行率与传播能力随非繁殖（越冬）纬度的降低而升高；而生境选择假说（habitat selection hypothesis）则预测，海洋生境中的病原体流行率低于淡水生境。为检验这两个尚未得到充分研究的假说，我们沿澳大利亚的纬度梯度，对越冬与居留型涉禽（鸻形目（Charadriiformes））开展禽疟血寄生虫（疟原虫属（Plasmodium）与血变原虫属（Haemoproteus spp.））筛查。我们对感染样本进行测序，以明确越冬候鸟是否与当地居留涉禽共享疟原虫谱系，并将流行率检测结果与已发表数据整合，开展全球比较分析。澳大利亚涉禽的禽疟流行率为3.56%，且部分寄生虫谱系在越冬候鸟与……