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Final Report

Initial | Fragmentation | Amphibians | Bats | Monitoring | SIVAM

Using Amphibians as Indicator Species

Why monitor amphibians?

        The relevant defining characteristic of amphibians that sets them apart from other creatures is the fact that they absorb a great deal of chemicals through their skin as well as through the thin, moist linings of their mouth and throat.  This makes them especially
sensitive to pollution present in the environment.  In addition to their wide distribution and large numbers throughout the rainforest, they make an ideal set of animals for the monitoring of toxin levels in the rainforest.  They also constitute a large enough food base for predators and a large enough controlling force for insects and other
animals that any disruption in the population numbers of this group of animals is likely to cause upheaval in the Amazonian food web.

Miscellaneous Chemicals of Possible Importance to the Project (copper
from mining, etc.)

CHEMICAL                   SPECIE          LIFE STAGE            

Copper Oxychloride    Xenopus                                     dose of
0.007-0.008%                48
Copper Sulfate        Xenopus laevis                                1.7
Ethyl Acetate        Xenopus laevis        3-4 weeks                180
Saccharin                Xenopus laevis        embryo                   17.94
(17.60-18.30) mg/mL                96
Anthracene        Rana pipiens        embryo                        0.065
         (after 30 min exposure to sunlight)
0.25 24
         (after 5 hrs exposure to sunlight)
Flouranthene        Rana pipiens        embryo                        0.09
Carbaryl                Xenopus laevis        embryo                        4.7
(3.9-5.6)                24

Works Cited:
1) Tyning, Thomas F.  Stokes Nature Guides: A Guide to Amphibians and
Reptiles.  Little, Brown and Company.  c1990.
2) Devillers, J. and Exbrayat, J. M.  Exotoxicity of Chemicals to
Amphibians.  Garden and Breach Science Publishers.  c1992.
3) Cockell, Charles S.  Ecosystems, Evolution, and Ultraviolet
Radiation.  Springer-Verlag.  c2001.
4) Devillers, J., Exbrayat J. M. Exotoxicity of Chemical to
Amphibians. Garden and Breach
Science Publishers.  c1992.