Declining Amphibian Populations: The Problem of Separating Human Impacts from Natural Fluctuations

@article{Pechmann1991DecliningAP,
  title={Declining Amphibian Populations: The Problem of Separating Human Impacts from Natural Fluctuations},
  author={Joseph H. K. Pechmann and David E. Scott and Raymond D. Semlitsch and Janalee P. Caldwell and Laurie J. Vitt and J. Whitfield Gibbons},
  journal={Science},
  year={1991},
  volume={253},
  pages={892 - 895}
}
Reports of declining amphibian populations in many parts of the world are numerous, but supporting long-term census data are generally unavailable. Census data from 1979 to 1990 for three salamander species and one frog species at a breeding pond in South Carolina showed fluctuations of substantial magnitude in both the size of breeding populations and in recruitment of juveniles. Breeding population sizes exhibited no overall trend in three species and increased in the fourth. Recent droughts… 
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