HEADWATERS
From the perspective of native fish species, the region's aquifers are absolutely essential to their survival. The Fall River Springs, which emerges from groundwater stored beneath Medicine Lake Volcano, is the largest spring system in the western United States. The trout of the Fall River thrive in the cold, nutrient-rich water from these springs, having shown the potential to reach populations of 5,000 fish per mile.
The Shasta River, which is a tributary of the Klamath River that emerges from springs on the northwest flank of Mt. Shasta, is a case study in how cold-water springs enhance salmon populations. The Shasta River is one of the most productive salmon streams in California relative to its water volume. Although in the early 1900s it contributed only 1 percent of the overall Klamath River's outflow, Shasta River accounted at that time for an astounding 50% of the Klamath's Chinook salmon population. The key to this productivity is the constant 55 degree Fahrenheit water temperature, which provides an ideal year-round habitat for trout, steelhead, and salmon. The other factor that benefits the salmon is the rich, geologically derived nutrients in the spring water that allow for abundant and healthy plant life and invertebrates, which in turn provide a plentiful food source for fish. Juvenile salmon grow rapidly in this ideal nursery and gain the size and strength they need to increase their odds of surviving the journey to the ocean.
Curtis Knight, CalTrout Executive Director, shares this perspective: "The springs are not just important to trout, steelhead, and salmon. These systems are telling us something important about the overall health of our watersheds. If there is a healthy wild trout population in the rivers of the Shasta area, we know that our water supply is healthy, too."
Why Fish Thrive in Spring-Fed Streams
"The springs are ... telling us something important about the overall health of
our watersheds. If there is a healthy wild trout population in the rivers of the
Shasta area, we know that our water supply is healthy, too."
- Curtis Knight, CalTrout Executive Director