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Yellowstone National Park Report

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In the past two decades, there has been increasing awareness of a general pattern of decline of amphibian species (Semlitsch 2003a). A variety of factors have been implicated in these declines, including habitat alteration, climate change, chemical contamination, disease, invasive species, and commercial exploitation. It is likely that these different hypothesized causes combine to reduce populations. For example, human development such as roads or houses may not only destroy habitat, but also facilitate introduction of chemicals, invasive species, and disease. Habitat degradation is much easier to reverse or mitigate than the other factors (Semlitsch 2002). Therefore, protecting habitat from excessive human disturbance may indeed be the most productive way to conserve amphibian populations.