Utah’s shrinking Great Salt Lake could spell disaster for millions of birds that depend on the briny body of water for food.
North America’s largest saltwater lake has been diminishing for years due to people redirecting its water for human use. Climate change-fueled drought ― including the extreme drought currently hammering the western United States ― has made it more severe.
The southern part of the lake is “just a couple inches above the historic low measurement taken in 1963,” according to a Friday statement from the U.S. Geological Survey. The agency said it anticipates the water will continue to drop over the next several months.
A comprehensive history of the lake from The Deseret News earlier this year noted that while the size of the lake has “always fluctuated,” an 11-foot drop in water levels ― which is a lot for the wide lake’s relatively shallow lake bed ― has occurred mostly over the last 10 years.
“Twenty years ago, this was under about 10 feet of water,” Kevin Perry, chairman of the department of atmospheric sciences at the University of Utah, told CNN. As he said that, he was riding a bike across the dry lake bed.
The lake is an important food source for an estimated 10 million migrating birds, according to a statement this week from the Utah Geological Survey. Those birds eat the lake’s brine shrimp and brine flies that, in turn, feed off of underwater reeflike rock mounds, called microbialites, that are created by microbes.
Receding water levels can expose the microbialites and threaten the lake’s entire ecosystem, the UGS warned. In the coming months, “a very significant proportion” are expected to be exposed, according to the agency.
The brine shrimp also play an important economic role for people, who harvest the creatures and sell them as fish food.
The lake is also an essential breeding habitat for pelicans. Dipping water levels have resulted in new land bridges being exposed between the mainland and the island where the birds nest, The Associated Press reported. Larger animals like foxes and coyotes can then cross to the island, which scares pelican parents away. The eggs and young are then vulnerable to being preyed on by seagulls.
Human health is also at risk. The lake bed soil is high in arsenic, and when water recedes and the ground dries out, wind blows that dust into the air. While the lake bed has a protective crust that prevents a lot of dust from getting into the area, that crust is getting damaged as people walk and even drive vehicles on it.
“The more continued drought we have, the more of the salt crust will be weathered and more dust will become airborne because there’s less of that protective crust layer,” Laura Vernon of Friends of the Great Salt Lake told the AP.
Wildlife biologist Jaimi Butler told CNN that thinking about keeping water in the Great Salt Lake is the “biggest thing” that keeps her up at night.
“We’re on the doorstep of a catastrophe,” she said.