By Jim Moore, Entomologist
Long before any human eyes ever gazed upon the pristine beauty of Eagle Lake in Lassen County, its one and only endemic and namesake trout species reigned supreme as the one and only fish-eating predator beneath the surface of its water. The Eagle Lake Trout is a Rainbow Trout subspecies (Oncorhynchus mykiss aquilarum; with the subspecies name ‘aquilarum’ meaning ‘eagle’ in the Latin language). In those days the trout were not limited to just the lake. The trout would swim up the creeks that flow into the lake to lay their eggs in the cool creek waters. The swim up Pine Creek, the primary spawning creek, would take the mature trout as far as four miles southwest of Highway 44 near the Bogard Rest Stop, a meandering journey nearly thirty miles long.
There were no roads, no railroad, no creek diversions, no cattle grazing pastures along the length of Pine Creek, and no humans. The Pine Creek pastures were mountain ‘meadows’ back then, that held and released water into the creek a bit longer than happens today, providing the fingerling trout a larger and healthier habitat to grow in before they made their journey down to Eagle Lake.
When the young trout first entered the lake they passed from the cooler fresh creek water habitat into the warmer, more alkaline water of Eagle Lake, a bit north of the present community of Spaulding. The lakes alkalinity was, and still is, sufficient enough to kill most other fish species that would be later stocked in the lake by humans. The Eagle Lake Trout has adapted to the lakes’ alkalinity, and is the only fish-eating game fish that can live and survive in the lake. The higher alkalinity of the lake, averaging about ph9, is mostly due to the fact that for eons the water that flows into the lake, is never sufficient to overflow the lake, thus slowly resulting in the lakes’ current alkalinity.
The young fish would disperse to all parts of Eagle Lake, which is a large natural lake with about 100 miles of irregular shoreline, comprising around 27,000 acres of surface water. The lake hosts an abundant source of aquatic invertebrates for the young trout to feed on and grow. Most importantly, once they became big trout, the offspring of the Tui Chub – another smaller native Eagle Lake fish species, provide the trout with a more vital year round food source, especially important during the winter season.
Back in those early days the only predators of the Eagle Lake trout, would have been Osprey, Eagles, White Pelicans, Grebes, various ducks; and Bears, and yes wolves also, along Pine Creek during the spring spawning season. Eventually human predators migrated into the region, including the Mountain Maidu, and Paiute peoples, who began to fish and hunt at Eagle Lake. These first people lived in harmony with the ecosystem of the Eagle Lake area and caused no damage to the environment.
In the 1800’s, people of mostly European ancestry, began immigrating into Northeastern California in increasing numbers. The activities of these immigrants, and their descendants, in the areas of the Pine Creek watershed, coupled along with the already intermittent dry spring seasons, seriously diminished the spawning success of the Eagle Lake Trout. The result was a serious population decline in the Eagle Lake Trout. In the late 1940’s, fearing the possible extinction of the lakes premiere trout species, fish-and-game biologists blocked up-stream access, and began the annual harvesting of eggs and sperm from the mature trout attempting to swim up Pine Creek.
The young of Eagle Lake Trout are now first raised in fish hatcheries, and restocked annually into Eagle Lake. The slow process to restore the Pine Creek spawning watershed is currently underway, and, hopefully, will once again be used by the Eagle Lake Trout to perpetuate it species.
Meanwhile knowledgable anglers know that Eagle Lake offers a trout fishing experience second to none on the planet!