Research Unit of Biodiversity (CSIC, UO, PA), Gonzalo Gutiérrez Quirós s/n, Oviedo University - Campus Mieres, Edificio de Investigación, Mieres, Spain.
Centro de Investigación, Seguimiento y Evaluación, Rascafría, Spain.
PLoS One. 2020 Nov 30;15(11):e0242913. doi: 10.1371/journal.pone.0242913. eCollection 2020.
Infectious diseases are considered major threats to biodiversity, however strategies to mitigate their impacts in the natural world are scarce and largely unsuccessful. Chytridiomycosis is responsible for the decline of hundreds of amphibian species worldwide, but an effective disease management strategy that could be applied across natural habitats is still lacking. In general amphibian larvae can be easily captured, offering opportunities to ascertain the impact of altering the abundance of hosts, considered to be a key parameter affecting the severity of the disease. Here, we report the results of two experiments to investigate how altering host abundance affects infection intensity in amphibian populations of a montane area of Central Spain suffering from lethal amphibian chytridiomycosis. Our laboratory-based experiment supported the conclusion that varying density had a significant effect on infection intensity when salamander larvae were housed at low densities. Our field experiment showed that reducing the abundance of salamander larvae in the field also had a significant, but weak, impact on infection the following year, but only when removals were extreme. While this suggests adjusting host abundance as a mitigation strategy to reduce infection intensity could be useful, our evidence suggests only heavy culling efforts will succeed, which may run contrary to objectives for conservation.
传染病被认为是对生物多样性的重大威胁,但在自然界中减轻其影响的策略却很少且大多不成功。蛙壶菌病导致了全球数百种两栖动物的衰落,但仍缺乏一种可以在自然栖息地应用的有效疾病管理策略。一般来说,很容易捕捉到两栖动物的幼虫,这为确定改变宿主丰度的影响提供了机会,因为宿主丰度被认为是影响疾病严重程度的关键参数。在这里,我们报告了两项实验的结果,这些实验旨在调查在遭受致命两栖类壶菌病的西班牙中部山区,改变宿主丰度如何影响两栖类种群的感染强度。我们的实验室实验结果支持了这样一个结论,即在低密度饲养蝾螈幼虫时,密度变化对感染强度有显著影响。我们的野外实验表明,减少野外蝾螈幼虫的数量也会显著影响次年的感染强度,但只有在去除量极端的情况下才会如此。虽然这表明调整宿主丰度作为减轻感染强度的策略可能是有用的,但我们的证据表明,只有大量捕杀才能成功,这可能与保护目标背道而驰。