Assessing Potential Risk to Alligators, Alligator mississippiensis, from Nutria Control with Zinc Phosphide Rodenticide Baits

  • Gary W. Witmer
  • John D. Eisemann
  • Thomas M. Primus
  • Jeanette R. O’Hare
  • Kelly R. Perry
  • Ruth M. Elsey
  • Phillip L. TrosclairIII
Article

Abstract

Nutria, Myocastor coypus, populations must be reduced when they cause substantial wetland damage. Control can include the rodenticide zinc phosphide, but the potential impacts to American alligators, Alligator mississippiensis, must be assessed. The mean amount of zinc phosphide per nutria found in nutria carcasses was 50 mg. Risk assessment determined that a conservative estimate for maximum exposure would be 173 mg zinc phosphide for a 28 kg alligator, or 6.2 mg/kg. Probit analysis found an LD50 for alligators of 28 mg/kg. Our studies suggest that the use of zinc phosphide to manage nutria populations would pose only a small risk to alligators.

Keywords

Alligator Nutria Residues Zinc phosphide 

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Copyright information

© US Government 2010

Authors and Affiliations

  • Gary W. Witmer
    • 1
  • John D. Eisemann
    • 1
  • Thomas M. Primus
    • 1
  • Jeanette R. O’Hare
    • 1
  • Kelly R. Perry
    • 2
  • Ruth M. Elsey
    • 3
  • Phillip L. TrosclairIII
    • 3
  1. 1.USDA/APHIS Wildlife ServicesNational Wildlife Research CenterFort CollinsUSA
  2. 2.USDA/APHIS Wildlife ServicesNational Wildlife Research CenterOlympiaUSA
  3. 3.Louisiana Department of Wildlife and FisheriesRockefeller Wildlife RefugeGrand ChenierUSA

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