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1 1 1 unreliable because there was only a single recapture event. However, the more reliable 1993, 1998 and 1999 estimates averaged only 163 animals and provided persuasive evidence of a downward trend in abundance. Those estimates were more convincing because of the higher number offish captured and recaptured and resultant relatively small values for coefficients of variation (CV) and confidence intervals. Regression analyses of abundance estimates (ln) as a function of time that were available between 1990 to 1999, conducted both with and without sparse data years 1994 and 1996, detected significant declines in abundance from about 500 animals in 1990 to about 100 animals in 1998 and 1999. Data from 1990 to 1992 were included in each of the early and later analyses because that was when PIT tags replaced Carlin tags. This was important because tag type may play a role in tag retention, number of recaptures observed, and subsequent abundance estimates. It also seemed reasonable to include that data in each analysis, because that was the time during which population status may have been changing. Regression analysis including years 1985 to 1999 also suggested a significant decline in population abundance. Survival estimates.-Survival estimates were generated with the recaptures only model in program MARK for time periods 1980 to 1992 and 1990 to 1999. Model goodness-of--fit to the data was assessed with program RELEASE in MARK and was deemed adequate (a non- significant chi-square test, P = 0.93). Model selection by AIC suggested the overwhelming model choice for each time period was constant ~ with time-varying p. Apparent survival, ~, was 0.728 (SE = 0.0287) for the time period 1980 to 1992, and was 0.762 (SE = 0.0475) for 1990 to 1999. The larger SE for ~ from 1990 to 1999 reflected the fewer years of sampling and the lower number of individuals recaptured. 15