Changes in the amount and timing of the discharge of major Eurasian Arctic rivers have been well documented, but whether or not these changes can be attributed to climatic factors or to the construction of man made reservoirs remains unclear. A new research report helps to identify the key processes (snow cover and air temperature) that have regulated seasonal stream flow fluctuations in the Eurasian Arctic over the last half-century (1958–1999) and to understand the regional coherence of timing trends, using a set of Eurasian Arctic rivers selected specifically because they are free of known effects of dams. A shift toward the earlier onset of spring runoff as measured by a modest change in the spring pulse onset (26 of 45 stations) and a strong change in the timing (39 of 45 stations). Winter stream flows increased over the period of record in most rivers, suggesting that trends observed by others in larger regulated Eurasian Arctic rivers may not be entirely attributable to reservoir construction.