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Changes in species richness between 1992–1993 and 2006–2007. The graph shows number of locations containing 0, or at least 1, 2, 3, or 4 species of amphibians in 1992–1993 and 2006–2008. Of the 21 ponds lacking amphibians in 2006–2008, 11 were dry all 3 years. Changes in pond richness are highly significant (Paired t test: t = 5.6848, P = 1.214E-06).
