Surviving extremes and fluctuations
Great Salt Lake is always changing. Conditions vary with location, with the seasons, and from one year to the next. In order to survive, the plants, animals and microbes that live in and around Great Salt Lake must be able to adjust to their constantly changing environment. But they also must survive the lake's often extreme conditions.
Some of the challenges that the organisms of Great Salt Lake face include:
Great Salt Lake is between 3.5 and 8 times saltier than the ocean. The organisms that live in the water have special adaptations that allow them to survive such saline conditions.
Air blocks much of the sun's DNA-damaging ultraviolet light from reaching the surface of the earth. But at an elevation of 4,200 feet, there is less air above Great Salt Lake than there is at sea level, and ultraviolet light levels are about 15% higher.
Great Salt Lake is an average of just 14 feet deep, with a maximum depth of 33 feet. Its shallow depth means that much of its surface area is exposed to the air, and is subject to its seasonal temperature fluctuations. Water temperatures vary from below freezing in the winter to more than 80 degrees Fahrenheit in the summer.
The water level changes a lot from year to year. When less water than normal flows into the lake, water levels drop and salinity rises. The shoreline recedes and wetlands dry up. Low water levels sometimes connect islands to the shore, exposing bird nesting areas to predators. During high precipitation years, lake levels rise and salinity drops. The shoreline expands and wetlands get covered by salt water, sometimes killing sensitive plants and destroying wildlife habitats. Even within a single year, it's normal for the water level to change by 2 to 3 feet. In some areas, a one foot change in elevation can cause the shoreline to move as much as one mile.