| Complete, long-term data sets, focused on a single species, and conducted with the involvement of a single individual, are very rare. Although 20 years of data collected on California tiger salamander presence and reproduction was not intended to be used to determine appropriate monitoring duration periods, this robust data set allows for detailed analysis. These data were grouped in 16 sequential 5-year monitoring periods and 11 sequential 10-year monitoring periods. This type of analysis showed that each different monitoring period indicated a different degree of decline, perceived increase, or relative stability. A plurality of the monitoring windows indicated that the population was in decline. However, the 20-year monitoring window showed that the population was stable or slightly increasing. These data suggest that longer monitoring periods provide a more accurate representation of the overall population trends in California tiger salamanders in Central California.
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