The role of native and introduced birds in transmission of avian malaria in Hawaii
The role of native and introduced birds in transmission of avian malaria in Hawaii
复制标题
本地和引进鸟类在夏威夷禽疟疾传播中的作用
DOI：
10.1002/ecy.3038
复制
发表时间：
2020
期刊：
影响因子：
4.8
通讯作者：
Kilpatrick, A. Marm
中科院分区：
文献类型：
--
作者：
McClure, Katherine M.;Fleischer, Robert C.;Kilpatrick, A. Marm
外来物种的引入和本土生物多样性的减少导致了全球病媒和宿主社区的重大变化，但对病原体传播的后果知之甚少。在低地夏威夷，鸟类群落主要由引进物种组成，分散的种群中有丰富的本土物种。我们研究了鸟类宿主群落组成，特别是本地和引进物种的作用，以及宿主多样性对南方家蚊(Culex Ququiefasciatus)禽流感流行的影响。我们还探讨了疟疾传播对当地宿主人口和人口学的相互影响。蚊虫中禽流感感染率随着本地鸟类密度和相对丰度以及宿主群落能力的增加而增加，但与宿主多样性无关。据估计，禽类疟疾传播会使华支睾吸虫(Hawai‘iʻamakihi)的种群增长率下降7-14%，但疟疾的死亡率不能解释该物种在我们现场的分布差距。我们的结果表明，在夏威夷，本土寄主物种增加了病原体对蚊子的传播，但引入的物种也可以单独支持疟疾传播。随着本地鸟类数量的增加，病原体传播的增加导致了本地鸟类更多的疾病死亡率，进一步增加了生态反馈周期中的疾病影响。此外，在没有本地鸟类的地点，媒介丰度较高，这盖过了宿主群落组成对传播的影响，即在没有本地鸟类的地点，受感染蚊子的丰度最高。由于病媒丰度较高，这些地点的疾病风险较高，可能会阻碍本地物种重新定居和恢复到这些地区。更广泛地说，这项工作表明了本地和引进分类群之间对病原体的寄主能力的差异如何影响传播，并强调了在其他系统中检查这一问题以确定这一结果的普遍性的必要性。
The introduction of nonnative species and reductions in native biodiversity have resulted in substantial changes in vector and host communities globally, but the consequences for pathogen transmission are poorly understood. In lowland Hawaii, bird communities are composed of primarily introduced species, with scattered populations of abundant native species. We examined the influence of avian host community composition, specifically the role of native and introduced species, as well as host diversity, on the prevalence of avian malaria (Plasmodium relictum) in the southern house mosquito (Culex quinquefasciatus). We also explored the reciprocal effect of malaria transmission on native host populations and demography. Avian malaria infection prevalence in mosquitoes increased with the density and relative abundance of native birds, as well as host community competence, but was uncorrelated with host diversity. Avian malaria transmission was estimated to reduce population growth rates of Hawai‘i ʻamakihi (Chlorodrepanis virens) by 7–14%, but mortality from malaria could not explain gaps in this species’ distribution at our sites. Our results suggest that, in Hawaii, native host species increase pathogen transmission to mosquitoes, but introduced species can also support malaria transmission alone. The increase in pathogen transmission with native bird abundance leads to additional disease mortality in native birds, further increasing disease impacts in an ecological feedback cycle. In addition, vector abundance was higher at sites without native birds and this overwhelmed the effects of host community composition on transmission such that infected mosquito abundance was highest at sites without native birds. Higher disease risk at these sites due to higher vector abundance could inhibit recolonization and recovery of native species to these areas. More broadly, this work shows how differences in host competence for a pathogen among native and introduced taxa can influence transmission and highlights the need to examine this question in other systems to determine the generality of this result.