Effects of host species and environmental factors on the prevalence of Batrachochytrium dendrobatidis in northern Europe

PLoS One. 2018 Oct 25;13(10):e0199852. doi: 10.1371/journal.pone.0199852. eCollection 2018.

Abstract

The fungal pathogen Batrachochytrium dendrobatidis (Bd) poses a major threat to amphibian populations. To assist efforts to address such threats, we examined differences in Bd host infection prevalence among amphibian species and its relations to both local environmental factors in breeding habitats and landscape variables measured at three scales (500, 2000 and 5000 m radii) around breeding sites in southernmost Sweden. We sampled 947 anurans of six species in 31 ponds and assessed their infection status. We then examined correlations of infection prevalence with canopy cover, pond perimeter and pH (treated as local-scale pond characteristics), and the number of ponds, area of arable land, area of mature forest, number of resident people and presence of sea within the three radii (treated as landscape variables). The Bd infection prevalence was very low, 0.5-1.0%, in two of the six anuran species (Bufo bufo and Rana temporaria), and substantially higher (13-64%) in the other four (Bombina bombina, Bufotes variabilis, Epidalea calamita, Rana arvalis). In the latter four species Bd infection prevalence was positively associated with ponds' pH (site range: 5.3-8.1), and negatively associated with areas of mature forest and/or wetlands in the surroundings. Our results show that the infection dynamics of Bd are complex and associated with host species, local pond characteristics and several landscape variables at larger spatial scales. Knowledge of environmental factors associated with Bd infections and differences in species' susceptibility may help to counter further spread of the disease and guide conservation action plans, especially for the most threatened species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agriculture
  • Animals
  • Anura / microbiology
  • Breeding
  • Bufonidae / microbiology
  • Chytridiomycota / genetics*
  • Chytridiomycota / physiology*
  • Conservation of Natural Resources
  • Ecosystem*
  • Environment
  • Europe
  • Geography
  • Host Specificity
  • Hydrogen-Ion Concentration
  • Mycoses / veterinary*
  • Prevalence
  • Ranidae / microbiology
  • Species Specificity
  • Sweden

Associated data

  • Dryad/10.5061/dryad.3mr46n0

Grants and funding

This work was supported by Carl Trygger's Foundation 15:220 and KF17:14 (JH). http://www.carltryggersstiftelse.se/, and Formas - Swedish Research Council for sustainable development 215-2014-594 (JH). http://www.formas.se/en/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.