Thousands of birds were discovered dead at the Salton Sea last month, raising new concerns about the lake's declining health. KVCR's Benjamin Purper has more in this feature report.
I’m at the Sonny Bono National Wildlife Refuge at the southern end of the Salton Sea. There are hundreds, maybe thousands of birds here today, using the Salton Sea’s wetlands as one stop along the Pacific flyway for migratory birds.
But just last month, this same refuge was the site of a gruesome bird die-off, where California Department of Fish & Wildlife workers cleaned up thousands of bird carcasses.
Jones: “What happened in mid-January is the hunters near the Sonny Bono National Wildlife Refuge discovered a lot of dead ducks. And they alerted the California Department of Fish & Wildlife. And they saw thousands of dead ducks.”
Andrea Jones is Director of Bird Conservation for Audubon California. She says that the birds all fell victim to a contagious disease known as avian cholera.
Jones: “So that's what happened, thousands of birds died in a couple week stretch from a disease that is not entirely uncommon for birds, particularly ducks or geese when they crowd into situations instead of having a lot of habitat. If they get too crowded they can have these outbreaks of disease.”
The birds are crowded because their habitat is actively shrinking. The man-made Salton Sea is receiving less and less water from agricultural run-off and the Colorado River, causing it to shrink dramatically.
Tim Krantz is a professor of environmental studies at the University of Redlands, and a renowned expert on the Salton Sea. He says the shrinking sea leads to less habitat for migratory birds. That leads to them being concentrated in small areas.
Krantz: “And so they're going there, and they all get concentrated there, if there are some diseased individuals and then they get concentrated just beak-to-beak, wing-to-wing, they're so crowded on the fields and then the water, at the south end particularly. Then that is the place where the contagion is going to manifest itself. And you get these outbreaks of avian cholera, Newcastle's disease, and so on.”
But that’s not the only way birds are being affected by the lake’s decline. The lake has become saltier as it’s shrunk, killing off nearly every species of fish that migratory birds rely on for food.
Krantz: “As you turn the tap off on the sea, the salinity goes exponential. And so the salinity spikes, has already spiked, the Salton Sea fishery is essentially gone. There's still some tilapia out there, even those are not reproductive anymore. So a couple more years, there will be no fish in the sea.”
And the lake’s shrinking isn’t just bad for birds – it’s also bad for humans. As the lake shrinks and more lakebed is exposed, the salts that were in the water go into the air. They’re then breathed in by humans.
Krantz: “These are super-fine silts, two millionths of a meter, two microns in size, I can get a hundred in the width of a human hair. Fifty-thousand in the space of a sugar cube. If you breathe these sediments into these lungs you can't cough them out, they're too small - they'll profuse directly through your lung tissue into your bloodstream, carrying with them the minerals that are attached to them... arsenic, selenium, cadmium, bad stuff.”
That could lead to a public health disaster as more of the lakebed is exposed.
Krantz: “So the issue is no longer fish and wildlife, although it's critical on the Pacific Flyway. The issue became human health and the potential health disaster that is going to happen as the quantification settlement is implemented.”
For Andrea Jones, the bird die-off is a sign that the state needs to address the issue of the Salton Sea immediately.
Jones: “It's a wake up call. Or an alarm bell. We knew something like this could happen, and it's a call to action to the state to get the habitats built, that they are in the process of designing at the Salton Sea.
Jones says that addressing the sea’s health is critical to both birds and humans.
Jones: “We need to get the word out that both for the health of the birds and for the health of the people in the region, we need to do something about the Salton Sea as quickly as possible.”