Biodiversity and Conservation

, Volume 20, Issue 9, pp 1911–1920 | Cite as

Species-level correlates of susceptibility to the pathogenic amphibian fungus Batrachochytrium dendrobatidis in the United States

  • Betsy A. Bancroft
  • Barbara A. Han
  • Catherine L. Searle
  • Lindsay M. Biga
  • Deanna H. Olson
  • Lee B. Kats
  • Joshua J. Lawler
  • Andrew R. Blaustein
Original Paper


Disease is often implicated as a factor in population declines of wildlife and plants. Understanding the characteristics that may predispose a species to infection by a particular pathogen can help direct conservation efforts. Recent declines in amphibian populations world-wide are a major conservation issue and may be caused in part by a fungal pathogen, Batrachochytrium dendrobatidis (Bd). We used Random Forest, a machine learning approach, to identify species-level characteristics that may be related to susceptibility to Bd. Our results suggest that body size at maturity, aspects of egg laying behavior, taxonomic order and family, and reliance on water are good predictors of documented infection for species in the continental United States. These results suggest that, whereas local-scale environmental variables are important to the spread of Bd, species-level characteristics may also influence susceptibility to Bd. The relationships identified in this study suggest future experimental tests, and may target species for conservation efforts.


Amphibian Batrachochytrium dendrobatidis Body size Infection Life-history pathogen 



Batrachochytrium dendrobatidis


Random forest


Out of bag



We would like to thank T.T. Young, B. Blaustein, S. Andrews, J. Martin, L. Payton, O. Howlin, E. Girvetz, R. Bancroft, S. Bancroft, and J. Ng for assistance. B. Han was funded by an NSF Postdoctoral Research Fellowship in Biology.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Betsy A. Bancroft
    • 1
    • 6
  • Barbara A. Han
    • 2
  • Catherine L. Searle
    • 3
  • Lindsay M. Biga
    • 3
  • Deanna H. Olson
    • 4
  • Lee B. Kats
    • 5
  • Joshua J. Lawler
    • 1
  • Andrew R. Blaustein
    • 3
  1. 1.School of Forest ResourcesUniversity of WashingtonSeattleUSA
  2. 2.Odum School of EcologyUniversity of GeorgiaAthensGreece
  3. 3.Department of ZoologyOregon State UniversityCorvallisUSA
  4. 4.USDA Forest ServicePacific Northwest Research StationCorvallisUSA
  5. 5.Natural Science Division, Seaver CollegePepperdine UniversityMalibuUSA
  6. 6.Department of BiologySouthern Utah UniversityCedar CityUSA

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