Biological Invasions

, Volume 10, Issue 3, pp 335–345 | Cite as

An invasive frog, Eleutherodactylus coqui, increases new leaf production and leaf litter decomposition rates through nutrient cycling in Hawaii

  • Hans Sin
  • Karen H. BeardEmail author
  • William C. Pitt
Original Paper


A frog endemic to Puerto Rico, Eleutherodactylus coqui, invaded Hawaii in the late 1980s, where it can reach densities of 50,000 individuals ha−1. Effects of this introduced insectivore on invertebrate communities and ecosystem processes, such as nutrient cycling, are largely unknown. In two study sites on the Island of Hawaii, we studied the top-down effects of E. coqui on aerial, herbivorous, and leaf litter invertebrates; herbivory, plant growth, and leaf litter decomposition rates; and leaf litter and throughfall chemistry over 6 months. We found that E. coqui reduced all invertebrate communities at one of the two study sites. Across sites, E. coqui lowered herbivory rates, increased NH 4 + and P concentrations in throughfall, increased Mg, N, P, and K in decomposing leaf litter, increased new leaf production of Psidium cattleianum, and increased leaf litter decomposition rates of Metrosideros polymorpha. In summary, E. coqui effects on invertebrates differed by site, but E. coqui effects on ecosystem processes were similar across sites. Path analyses suggest that E. coqui increased the number of new P. cattleianum leaves and leaf litter decomposition rates of M. polymorpha by making nutrients more available to plants and microbes rather than through changes in the invertebrate community. Results suggest that E. coqui in Hawaii has the potential to reduce endemic invertebrates and increase nutrient cycling rates, which may confer a competitive advantage to invasive plants in an ecosystem where native species have evolved in nutrient-poor conditions.


Amphibian Decomposition rate Eleutherodactylus coqui Invasive Non-native Productivity Tropics 



We thank Kamehameha Schools and Hawaii's Division of Forestry and Wildlife for allowing access to work on their lands. This research was supported by USDA/APHIS/WS/NWRC, Jack Berryman Institute at Utah State University, US Fish and Wildlife Service, and Hawaii Department of Natural Resources (Hawaii Invasive Species Council). We thank S. Durham and G. P. Kyle for statistical advice and R. McGuire, L. Hamilton, and D. Grant for field and laboratory assistance.


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Department of Wildland Resources and the Ecology CenterUtah State UniversityLoganUSA
  2. 2.USDA/APHIS/WS/National Wildlife Research Center, Hilo Field StationHiloUSA

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