Significant reductions of host abundance weakly impact infection intensity of Batrachochytrium dendrobatidis

PLoS One. 2020 Nov 30;15(11):e0242913. doi: 10.1371/journal.pone.0242913. eCollection 2020.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphibians / genetics*
  • Amphibians / growth & development
  • Amphibians / microbiology
  • Animals
  • Batrachochytrium / genetics*
  • Batrachochytrium / pathogenicity
  • Biodiversity
  • Chytridiomycota / genetics
  • Ecosystem
  • Larva
  • Mycoses / genetics
  • Mycoses / microbiology*
  • Population Dynamics
  • Spain / epidemiology
  • Urodela / genetics*
  • Urodela / growth & development
  • Urodela / microbiology

Grants and funding

This study has been supported by Fundación BBVA and Organismo Autónomo Parques Nacionales (Spain, project ref. 2399/2017; J.B.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors did not receive a salary from any of our funders.