GREAT SALT LAKE

Increasing Great Salt Lake salinity predicted to impact Utah brine shrimp

Oct 3, 2022, 11:39 AM | Updated: 11:39 am
(Francisco Kjolseth | The Salt Lake Tribune) Glossy ibis fly over the Bear River Migratory Bird Ref...
(Francisco Kjolseth | The Salt Lake Tribune) Glossy ibis fly over the Bear River Migratory Bird Refuge, a 74,000-acre nature reserve in the northern Great Salt Lake in June 2021.
(Francisco Kjolseth | The Salt Lake Tribune)

SALT LAKE CITY — New research suggests that as Great Salt Lake shrinks and gets saltier, brine shrimp, a staple food for migrating birds and a boon to Utah’s economy, may be in danger of dramatic population declines.

Brine shrimp are hardy crustaceans that live in the warm salty waters of Great Salt Lake. The brine shrimping industry, that harvests brine shrimp eggs, called cysts, to sell to aquaculture businesses as fish food, brings in millions of dollars to Utah’s economy each year, and many birds that use the lake to nest or refuel during migration rely on them for food. However, with the lake shrinking due to drought and water consumption, a new model suggests our brine shrimp are at risk.

Gary Belovsky, an emeritus professor at the University of Notre Dame, created a model that helps predict how well brine shrimp cysts, larvae, and adults survive up to five years into the future, depending on Great Salt Lake conditions, including salinity levels, food availability and type, and water temperature.

By adjusting lake conditions, Belovsky can predict what may happen to the brine shrimp population. While the type of food and the amount available is a powerful driver of how well brine shrimp can survive and reproduce, as Great Salt Lake gets increasingly salty as it dries up, Belovsky’s model predicts high salt levels will spell trouble for the shrimp.

“What is the effect of the higher salinities we’re seeing right now on the brine shrimp?…what would happen if the salinity goes to 18 percent?…I ran the model at that level, and within two years things really crash,” Belovsky explained.

Great Salt Lake salinity levels reached 18% in mid-September.

Adult brine shrimp die each year over the winter, but before they do, they lay cysts that hatch the next spring when conditions are right. At these high salt levels, brine shrimp have to spend a significant amount of energy managing salt levels in their bodies, leaving them with little energy to produce cysts. As a result, with fewer brine shrimp hatching each spring, the population may not be able to sustain itself, leading to a dramatic population decline.

Fortunately, spring snowmelt and rain often bring enough water to Great Salt Lake that salinity levels drop in the springtime, giving the brine shrimp a break from high salt levels and a chance to put energy into producing the next generation of brine shrimp. But, as the lake shrinks and gets increasingly salty, we may reach a point where even seasonal inflows won’t bring salinity levels below 18 percent.

This year’s monsoon season has helped alleviate drought conditions across the state and may be increasing water flows headed toward Great Salt Lake. However, Belovsky said with high water consumption across northern Utah, the rain hasn’t been enough.

“Rain is not getting to the lake. It’s either being used before it gets to the lake or it’s evaporating faster than it used to be…I would guess it’s being used,” Belovsky said.

Although brine shrimp are small, they’re a critical food source for millions of migratory birds that stop at Great Salt Lake to refuel. Eared grebes, which are small waterbirds, eat almost exclusively brine shrimp to build fat stores for migration and grow new feathers.

Michael Conover, a USU professor, said up to 95% of all eared grebes in North America stop at Great Salt Lake during migration.

“If you’re looking at when the grebes are on the Great Salt Lake, it’s 95%…once eared grebes are here, they cannot fly. So they’re stuck. And if they could fly, there’s no other hypersaline lake in North America that could sustain them all. So it could be a dark future,” Conover said.

Drought and water consumption are changing the relationship between birds and brine shrimp in other ways as well.

John Luft, who manages the Great Salt Lake Ecosystem Program for the Utah Division of Wildlife Resources, said northern shovelers, a species of duck that normally eats seeds that collect in bays around the lake, have instead been venturing farther from shore in the winter to eat brine shrimp cysts because the bays they typically feed in are dry or frozen.

While adult brine shrimp provide plenty of nutrients for birds that eat them, like eared grebes, brine shrimp cysts don’t offer the same benefits. As a result, shovelers that have been eating their fill of cysts are failing to digest them and get enough nutrients from the cysts to survive.

“We actually saw shovelers that were starving to death…and we’ve had that happen a couple of different years. We had it happen this year…I mean, the birds would be basically emaciated,” Luft said. “So we sent them in for testing, because well, maybe it’s a disease. There was no disease associated with it. It was just that they were starving to death, but that was the only food source that they had.”

Recent initiatives to reduce state water consumption and allocate water to Great Salt Lake offer some hope for the lake’s water and salinity levels, but Utah’s growing population and ongoing drought conditions are likely to put increased stress on Utah’s water systems in the future.

KSL 5 TV Live

Top Stories

Great Salt Lake

Great Salt Lake shrinking...
Matt Rascon

KSL+: Growing concerns over a shrinking lake

Four months after we first dove into the topic on this show, the shrinking Great Salt Lake remains a top issue for scientists, lawmakers and the media.
15 days ago
(KSL TV)...
Dan Spindle

Antelope Island on life support due to shrinking Great Salt Lake, experts say

It’s supposed to be surrounded by water, but right now, Antelope Island as we know it is on life support — suffering from the shrinking Great Salt Lake.
16 days ago
This image shows the growing shoreline of the shrinking Great Salt Lake. (KSL TV)...
Cary Schwanitz

Gov. Cox suspends new water rights in the Great Salt Lake Basin

Gov. Spencer Cox issued a proclamation Thursday that puts new water rights applications on hold in the Great Salt Lake Basin for the time being.
29 days ago
Birds fly over and nest along the Great Salt Lake wetlands near Corrine, Box Elder County, on Wedne...
Carter Williams

New initiative aims to get people to ‘fall in love’ with the Great Salt Lake again

A U.S. waterfowl conservation organization is making the Great Salt Lake the spotlight of a new nationwide initiative — with Utah's help along the way.
30 days ago
Students from the Horizonte Instruction and Training Center to visit with Kevin Perry from the Utah...
Mike Anderson

High school students learn about dangers of shrinking Great Salt Lake

Students from the west side of Salt Lake City took a field trip to Antelope Island Thursday to see the expanding lakebed of the Great Salt Lake.
1 month ago
Riley Niederhauser, a Salt Lake City Public Lands Department crew member, repairs sprinklers in Lib...
Carter Williams

Can a tax code amendment help Utahns conserve water?

SALT LAKE CITY — As ongoing drought conditions continue to pummel the West, a Utah water conservation advocacy group believes a tweak in the state’s tax code can be a major driver toward water consumption reduction goals according to a story at KSL.com. Public records show that Utah charges much more in property taxes than […]
1 month ago

Sponsored Articles

house with for rent sign posted...
Chase Harrington, president and COO of Entrata

Top 5 reasons you may want to consider apartment life over owning a home

There are many benefits of renting that can be overshadowed by the allure of buying a home. Here are five reasons why renting might be right for you.
Festive kitchen in Christmas decorations. Christmas dining room....
Lighting Design

6 Holiday Decor Trends to Try in 2022

We've rounded out the top 6 holiday decor trends for 2022 so you can be ahead of the game before you start shopping. 
Happy diverse college or university students are having fun on their graduation day...
BYU MBA at the Marriott School of Business

How to choose what MBA program is right for you: Take this quiz before you apply!

Wondering what MBA program is right for you? Take this quiz before you apply to see if it will help you meet your goals.
Diverse Group of Energetic Professionals Team Meeting in Modern Office: Brainstorming IT Programmer...
Les Olson

Don’t let a ransomware attack get you down | Protect your workplace today with cyber insurance

Business owners and operators should be on guard to protect their workplace. Cyber insurance can protect you from online attacks.
Hand turning a thermostat knob to increase savings by decreasing energy consumption. Composite imag...
Lighting Design

5 Lighting Tips to Save Energy and Money in Your Home

Advances in lighting technology make it easier to use smart features to cut costs. Read for tips to save energy by using different lighting strategies in your home.
Portrait of smiling practitioner with multi-ethnic senior people...
Summit Vista

How retirement communities help with healthy aging

There are many benefits that retirement communities contribute to healthy aging. Learn more about how it can enhance your life, or the life of your loved ones.
Increasing Great Salt Lake salinity predicted to impact Utah brine shrimp