Table 4. Parameter estimates from the overall top-ranked known-fate model of ruffed grouse overwinter survival at Sandhill. The effect of phenotypic mismatch with snow cover varied by winter field season suggesting that mismatch is variably important for determining overwinter survival. Percent of habitat covered by open habitat also had a negative effect on overwinter survival. The model included a common intercept, Mismatch1 – Mismatch5 (weekly time-varying individual covariates of mismatch for each field season, the proportion of days in a week an individual is phenotypically mismatched with snow cover) and % Open (a constant covariate for proportion of individual use area covered by Open habitat).