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Show the lake and its environs. North America's largest staging concentrations of American avocets and Black- necked stilts occur at GSL, and the largest breeding population of White- faced ibis occurs in the wetlands around the lake. These are only a few examples of the importance of the lake system in terms of bird use and local, national and international recognition as an important bird area. The aquaculture industry has spotlighted GSL due to the profitable brine shrimping industry. Brine shrimp ( Artemia) are harvested, marketed and utilized on five continents. The GSL harvest provides a significant quantity of high quality brine shrimp cysts ( also known as eggs) to the international market. Brine shrimp cysts and their nauplii ( larval brine shrimp) provide the live feed and protein for marine finfish and crustacean hatcheries around the world. The aquaculture industry is rapidly becoming a primary food source for humans. Aquatic Biology GSL aquatic biology has adapted to various saline conditions of GSL ecosystems. The interactions and relationships of the species can be complicated by environmental conditions which are constantly changing in this terminal basin lake. Salinity is a very important factor. The lake has differing characteristics in each of its main bays, but the significant differences are seen contrasting the north arm to the rest of the lake. The north arm receives limited inflow relative to the rest of the lake. The northern railroad causeway constructed between Promontory Point and Lakeside effectively separated Gunnison Bay from Gilbert Bay. The salinity of the north arm is significantly higher than the rest of the lake, and currently is close to saturation of sodium chloride. Currently there are six algal species in this arm. There are few functioning brine shrimp populations in the north arm, and none of significance. Brine shrimp and cysts are washed in from the south arm, but the adults soon perish due to high salinities. The cysts may persist longer, but cannot hatch and grow to adults for the same reason. There may be local sites where freshwater springs discharge into the north arm that allow a small area of the bay to sustain a brine shrimp population because the salinity is locally favorable. As salinities vary, brine shrimp population abundance will change. Relative to the vigorous biota of the south arm, the north arm is comparatively depopulate. The south arm, Farmington and Bear River Bays receive nutrient input from drainages of the GSL watershed. Nutrient data are available for some of these drainages, but the sampling points are located upstream from the freshwater marshes surrounding the lake. The cycling and discharge of the nutrients from these marshes to the lake has not been quantified at this time. The nutrients in the lake water are utilized by algae and bacteria. There are more species of algae and bacteria present in these three bays of the lake than in the very saline north arm. The numbers of species present and their abundance fluctuate with lake salinity. Algal production in the lake is, however, nitrogen limited ( Stephens and Gillespie, 1976 and Wurtsbaugh, 1988), but 68 |