Table S1.

Description of predictor variables in the linear mixed models used to describe trends in R. sierrae abundance

Variable name	Description
Year	Year in which survey was conducted
Day	Day of year on which survey was conducted
Water body depth	Maximum depth of water body (in meters) as estimated for deeper water bodies by sounding with a weighted line or visually for shallower water bodies (16)
Water body elevation	Elevation of the water body (meters above sea level) as estimated from 1:24,000 US Geological Survey topographic maps
Precipitation	Annual sum of monthly Merced River discharge in a given year divided by the annual sum of average monthly discharge during 1951–2000; provides a measure of the snowfall amount during the previous winter
Fish	Presence or absence of one or more species of nonnative trout as determined by gill netting for deeper water bodies or visually for shallower water bodies (16)
Watershed	Watershed in which the water body is located: Merced River or Tuolumne River
Observer	Leader of the team conducting the survey: G.M.F. or R.A.K.