You can’t visit Swan Falls; you can only visit where they were. Swan Falls Dam, on the Snake River, is the oldest dam on the river, constructed 1901-1903. It was also the beginning of the end for anadromous fish like salmon on the Snake. Today there are an appalling 19 dams on the Snake River, 15 of them in Idaho alone.
The two large white buildings are the old powerhouse; the smaller, low gray building to the right is the modern powerhouse, which went on line in 1994.
The Snake River Canyon itself is a microhabitat, warmer, better watered, and more protected than the surrounding Snake River Plain. As a result, it’s prime habitat for a variety of critters, certainly including birds, like yesterday’s American White Pelican, a species that generally migrates to southern California and Mexico.
Double-crested Comorants are another species that usually migrates, but a few hang around the Snake River for the winter. It seems to be unclear whether the behavior is a result of man’s alteration of the environment or predates the numerous dam reservoirs.
Waterbirds aren’t the only species that likes the canyon.
Sparrows love the brush verge along the river. There are enough bug hatches through the winter to support a small population of flycatchers, too.
But Swan Falls is best known for raptors, as a part of the Morley Nelson Snake River Birds of Prey National Conservation Area.1 Here’s a couple of samples:
That’s an example of the canyon wall behind the Harrier, at that point a nearly vertical 700 foot high wall of basalt. The basalt cools into columns which create ideal nesting places for the raptors. That, and the abundant prey – mostly mice, voles and ground squirrels – supports an amazing population of predator bird species.
The Snake River Canyon is also a geological marvel, a cut through the immense pile of lava and ash that is the Snake River Plain. We’ll get to the geology in the next post.