From Chapter 1:

...  The Dena'ina used the Susitna Valley Rivers as their pathways throughout the year. They are said to have developed the birch bark canoe to aid in their summer travels as they hunted and fished the abundant natural resources of the areas around the rivers that surge throughout the valley. Seasonal villages and traditional camping sites were scattered in locations up and down the valley and its rivers. Places like the land at the mouth of Kroto Creek, and the area near the mouth of the Talkeetna River (site of present day Talkeetna) were among these sites.
     The influence of the Russians and later the Americans who started to settle in the Dena'ina territory brought changes to the Dena'ina way of life. The Dena'ina attempted to continue to hunt and fish the lands near the valley's waterways, but animal populations slowly decreased with the influx of a white population. As time passed, the Dena'ina clustered around white settlements and their customs became diluted and altered by their new dependence on the white traders.
     Finally, with the discovery of gold in places like Cache Creek and the construction of the Alaska Railroad paralleling "the father of the earth," many of the Dena'ina gradually drifted away from their traditional Susitna Valley haunts. Their camping sites nestled in the birch and spruce trees along the rivers were abandoned and silent with time.

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...  Almost in step with the prospectors came the chasers of fur, the trappers, to the rivers and forests of the Susitna Valley. Sometimes the trappers stayed and settled into a life centered on their trapping in the winter and mining in the summer. Others trapped only until the easy fur was diminished and then they looked for new areas with abundant furs. Whether or not they settled or moved on they definitely pushed into even more remote corners of the lands between the rivers in search of new trap line grounds....