Spuller Lake Watershed

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The Spuller Lake basin (37°56'55"N, 119°17'2"W) is in the Hall Research Natural Area near Tioga Pass. Research began in 1989. Spuller Lake is shallow (mean depth 1.6 m) with little volume (34,700 m3), however in area (2.2 ha), it is similar to Emerald Lake. From November thorough June the lake is covered by 1 to 3 meters of ice, and this thickness corresponds to 50 to 85 % of the lake volume. Little or no thermal stratification occurs in Spuller Lake during the summer because of its shallow depth. In winter, the lake was inversely stratified and oxygen depletion occurred in the hypolimnion. At other times, lake waters are well oxygenated.
The watershed has a predominantly northeast aspect and large vertical relief (537 m). The V/A index is small (0.04 m) and the lake exerts little influence on outflow discharge or chemistry. The lake is supplied by one major inflow. The lower portions of the watershed are composed of ancient tuffaceous lake beds. These beds are fine-grained and thin and composed chiefly of volcanogenic sediment. Common minerals include plagioclase, quartz, biotite, hornblende and opaque minerals; calcareous layers contain calcite, diopside, hornblende, epidote and trace amounts of sheelite. Most of the watershed, however, is composed of talus and bedrock outcrops with associated Alpine Brown Soils. These rocks are dark-colored, medium-grained hornblende-biotite granodiorite. The watershed is nearly devoid of trees and most of the vegetation is confined to areas near the lake meadows of grass and sedges and small stands of dwarfed and stunted White Bark Pine dominate. A small population of reproducing Brown Trout is present.