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During the summers of 1984 and 1985, laser measurements were made of the distance from a reference location to markers on the surface of the lower reach of Columbia Glacier, Alaska. The data have numerous gaps, mostly because of inclement weather. The laser measurements were corrected for variations in atmospheric temperature and pressure and for the trajectory of the marker. The marker speed was calculated by using a combination of cubic splines and digital filters to arrive at a data set with 1-hour time intervals. The speed varies from 7 to 15 m/d and has three noteworthy components: (1) a low-frequency perturbation in speed with a time scale of days related to increased precipitation, (2) semidiurnal and diurnal variations related to sea tides, and (3) diurnal variations related to glacier surface melt. The low frequency and tidal period variations are separated by low-pass filtering and subtracting the filtered data from the original data. The variations from melt runoff and tides have the same frequency range and are examined using harmonic analysis and multiple regression with the various forcing functions. The high-frequency portion of the ice speed signal is dominated by tidal influences and to a lesser extent by meltwater influences. The low-frequency portion of the signal is dominated by the effects of precipitation. Kamb et al., 1985] and calving rates. As a result, an intensive field program in August and September 1984 collected data on ice calving, ice velocity, terminus position, meteorological variables, tide stage, and runoff from a marginal river (as a surrogate for subglacial discharge). This program is described in detail by Vaughn et al. [1985]. The purpose of this report is to analyze the ice speed data and relate its variations with variations in the various forcing functions. The primary focus is the ice speed derived from electronic distance meter (EDM) measurements (EDM, Figure 1); temperature, insolation, and precip- Recent glaciological research has indicated a need for the better understanding of the relation between ice flow and subglacial water flow [

We surveyed high-elevation lakes for long-toed salamander (Ambystoma macrodactylum) larvae and trout in the northern Bitterroot Mountains of Montana, U.S.A., in 1978Montana, U.S.A., in , 1997Montana, U.S.A., in , and 1998. Our objectives were to (i) test whether trout exclude salamander populations; (ii) determine whether lakes in which trout have gone extinct have since been colonized by salamanders; and (iii) estimate the rates of population extinction and colonization in lakes never stocked with trout. In agreement with previous work on the interactions between trout and long-toed salamanders, trout effectively excluded salamander populations from lakes. Somewhat surprisingly, however, salamanders managed to colonize lakes after the extinction of trout populations despite evidence of low levels of interpopulation dispersal in these salamander populations. In lakes never stocked with trout there was no evidence of a decline in salamander populations; 2 of these lakes were colonized and no populations went extinct.

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