University of Manitoba, 70-220 Dysart Road, Winnipeg, Manitoba, Canada.
Canadian Wildlife Service, Environment and Climate Change Canada, 351 St. Joseph Blvd, Gatineau, QC, Canada.
Parasitology. 2020 Jan;147(1):96-107. doi: 10.1017/S0031182019001240. Epub 2019 Sep 18.
Understanding factors that influence the spatial and temporal distributions of blood parasites is important to help predict how host species and their parasites may respond to global change. Factors that may influence parasite distributions are land cover and host dispersal patterns, which may result in exposure of a host to novel parasites, or escape from parasites of their origin. We screened golden-winged warblers from across the United States and Canada for blood parasites, and investigated whether land-use patterns or host dispersal affected the prevalence and composition of haemosporidian assemblages. Parasite prevalence varied strongly with study area, and areas with high agricultural cover had a significantly higher prevalence of Leucocytozoon and Parahaemoproteus parasites. Lineages of Parahaemoproteus and Leucocytozoon were genetically differentiated among study areas, and prevalence and composition of parasite assemblages indicated an increase in parasite prevalence and accumulation of unique parasite lineages from the southeast to the northwest. This matches the historical range expansion and natal dispersal patterns of golden-winged warblers, and suggests that golden-winged warblers may have been sensitive to novel parasites as they dispersed. The high prevalence and diversity of parasite lineages in the north-west extent of their breeding range (Manitoba) indicates that this population may face unique pressures.
了解影响血液寄生虫时空分布的因素对于帮助预测宿主物种及其寄生虫如何应对全球变化非常重要。可能影响寄生虫分布的因素是土地覆盖和宿主扩散模式，这可能导致宿主暴露于新的寄生虫，或逃避其起源的寄生虫。我们对来自美国和加拿大各地的金翅雀进行了血液寄生虫筛查，并调查了土地利用模式或宿主扩散是否会影响血孢子虫组合的流行率和组成。寄生虫的流行率与研究区域强烈相关，农业覆盖面积高的地区，Leucocytozoon 和 Parahaemoproteus 寄生虫的流行率显著更高。不同研究区域的 Parahaemoproteus 和 Leucocytozoon 谱系在遗传上存在分化，寄生虫组合的流行率和组成表明寄生虫流行率增加，独特的寄生虫谱系从东南向西北积累。这与金翅雀的历史分布范围扩张和出生地扩散模式相匹配，表明金翅雀在扩散过程中可能对新的寄生虫敏感。它们繁殖范围（曼尼托巴省）西北部寄生虫谱系的高流行率和多样性表明，该种群可能面临独特的压力。
