THE EAGLE LAKE FIELD STATION
DEPARTMENT OF BIOLOGICAL SCIENCES, CALIFORNIA STATE UNIVERSITY, CHICO
The Eagle Lake Field Station is located 26 miles northwest of Susanville, Lassen County, California, about 100 miles south of Oregon, 40 miles west of Nevada, and 300 miles northeast of San Francisco. California Routes 36 and 44 from the west and 395 from the north and south lead to Susanville. Eagle Lake can be reached by paved road (County road A-1), but the field station is at the end of 10 miles of dirt roads. The recommended route is to take Rt. 139 north from Susanville for 16 miles, turn left at the field station sign and follow the ELFS signs. The dirt roads are rough and rocky; 4-wheel drive is rarely necessary but a high-clearance vehicle is recommended. The field station itself is sited on 80 acres on the middle eastern shore of the lake. The land accessible to students and faculty is much greater - literally thousands of acres. The station is located within a sage / juniper woodland, but a variety of habitats (marshes, lakes, streams, montane coniferous forests, high desert) are very close by. Temperatures are typical for the eastern side of the Cascades with highs in the 90s and lows in the 50s during the summer months. Winters are cold, down to 0 degrees, and the lake freezes over regularly. Both rainfall and snow are moderate as the station is in the rain shadow of the Cascades.
Eagle Lake, the second largest freshwater lake entirely within the boundaries of California, lies in an isolated valley on the eastern side of the Cascade range. The remnant of a much larger Pleistocene lake, Eagle Lake covers about 30,000 acres and is nearly 14 miles long. Located at the juncture of four major geologic provinces, it is bordered on the west by the forested slopes of the Cascades, on the South by the Sierra Nevadas, on the east by the arid Great Basin Desert, and to the north and east by the Modoc Plateau. The terrain immediately around the lake ranges from the surface of the water at 5100 feet to the 8000 foot elevation of Fredonyer Peak to the northeast. The lake's geologic diversity provides for a unique set of ecological communities. Montane coniferous forests become interspersed with western juniper and mountain mahogany which give way to sage and rabbit brush to the east. The high pH of Eagle Lake (near 9) allows only 5 species of native fishes to thrive including the prized Eagle Lake subspecies of the rainbow trout. But the lake is quite productive with moderate numbers of invertebrates and fish eating birds. Volcanic ice caves on the west side of the lake support populations of cave crickets as well as other cave biota, and the lake supports one of California's largest breeding populations of western grebes.