Previous photo pair1919 - 2011: Alpine Mountains near Sanctuary14/19Next photo pair
gravel bar photo pair
Photo Credits: S.H. Cathcart (USGS) (1919), R.D. Karpilo (2011)
Ecoregion: Alaska Range Mountains
Change Type: Changing shrublines
Changing shrublines
Description:
This photo pair shows a general infilling of woody vegetation along the stream channel and an increase in shrubline on the bluff above it. Notice the light colored lichens in the foreground of the earlier photo? In the later photo you can see that these lichens are still present but are being overgrown by small shrubs. As the shrubs grow and shade out the lichens, the lichens will die, reducing an important winter food source for caribou. This picture was taken in the upper Sanctuary River Valley looking towards the region known as Refuge Valley.