Illera Juan Carlos, López Guillermo, García-Padilla Laura, Moreno Ángel
Research Unit of Biodiversity, Oviedo University, Mieres, Asturias, Spain.
Instituto de Biología de la Conservación, Málaga, Spain.
PLoS One. 2017 Sep 7;12(9):e0184587. doi: 10.1371/journal.pone.0184587. eCollection 2017.
Mountains are well-suited systems to disentangle the factors driving distribution of parasites due to their heterogeneity of climatic and habitat conditions. However, the information about the relative importance of environmental factors governing the distribution of avian haemosporidians on temperate mountains is very limited. The main goal of the present study is to identify the factors determining prevalence and richness in avian haemosporidians (Plasmodium, Haemoproteus and Leucocytozoon) at the community level along elevational gradients on two mountain ranges located around the northern and southern limits of the Iberian Peninsula (Spain). We used samples from 68 avian species and 1,460 breeding individuals caught over widespread woodland and open habitats. Our findings confirmed the importance of climatic variables explaining prevalence and richness on Iberian mountains. However, landscape variables and other factors named host richness and migration behaviour explained more variation than climatic ones. Plasmodium genus preferred open and warm habitats. Water sources were also important for the southern but not for the northern mountain. Haemoproteus and Leucocytozoon showed affinities for woodland areas. Climatic conditions for Haemoproteus and Leucocytozoon were dependent on the mountain range suggesting some adaptation of avian haemosporidian and their invertebrate vectors to the climatic particularities of both mountain massifs. In contrast to Plasmodium and Haemoproteus genera, Leucocytozoon prevalence and richness values were significantly higher in the southern mountain range. Overall, our findings at the community level has enriched the relative weight and effect direction of environmental factors governing the distribution and prevalence of the avian haemosporidian community. Also, our results provide a caution message about the precision of predictive models on parasite distributions based on climatic variables, since such predictions could overestimate the effect of climate change scenarios on the transmission of the haemosporidians.
由于山区气候和栖息地条件的异质性，山区是解开驱动寄生虫分布因素的理想系统。然而，关于控制温带山区鸟类血孢子虫分布的环境因素的相对重要性的信息非常有限。本研究的主要目标是确定在位于伊比利亚半岛（西班牙）南北边界附近的两条山脉上，沿海拔梯度在群落水平上决定鸟类血孢子虫（疟原虫、血变原虫和白细胞虫）的流行率和丰富度的因素。我们使用了从广泛的林地和开阔栖息地捕获的68种鸟类和1460只繁殖个体的样本。我们的研究结果证实了气候变量对解释伊比利亚山脉上的流行率和丰富度的重要性。然而，景观变量以及其他因素，即宿主丰富度和迁徙行为，比气候变量解释了更多的变异。疟原虫属更喜欢开阔和温暖的栖息地。水源对南部山脉很重要，但对北部山脉不重要。血变原虫和白细胞虫表现出对林地的偏好。血变原虫和白细胞虫的气候条件取决于山脉，这表明鸟类血孢子虫及其无脊椎动物媒介对两个山脉地块的气候特殊性有一定的适应性。与疟原虫属和血变原虫属相比，白细胞虫在南部山脉的流行率和丰富度值显著更高。总体而言，我们在群落水平上的研究结果丰富了控制鸟类血孢子虫群落分布和流行率的环境因素的相对权重和影响方向。此外，我们的结果对基于气候变量的寄生虫分布预测模型的准确性发出了警示，因为此类预测可能高估气候变化情景对血孢子虫传播的影响。
