Climatic warming has been correlated with poleward and upward distributional shifts of plants and animals but evidence from stream systems is very limited. To test for distributional shifts and concordance with climate-based predictions, in 2006 I re-sampled stonefly nymphs (Perlidae) at 35 sites I had surveyed 1977-78. Median elevations of the two focal stonefly species shifted uphill ~65 m. Logistic regression supports the shift (P<0.019) for Acroneuria abnormis but not for Eccoptura xanthenes. Additional samples (n=58) and examination of longitudinal patterns in individual streams provide further evidence for elevational change by both species. These changes are concordant in direction and magnitude with those reported for other systems and taxa. Stream networks and fauna in montane regions may be especially vulnerable to climate change.