RENO, Nev. (AP) — U.S. wildlife officials say there is enough evidence that a rare fish along the California-Nevada line may be at risk of extinction to warrant an annual review to determine whether it should be listed as endangered.
Conservationists who filed a March 2021 appeal to protect the Lake Valley tui chub Fish say populations of the 5-inch-long (13-centimeter-long) tui chub are declining in a single basin in Esmeralda County halfway between Reno and Las Vegas. .
They primarily blame over-pumping of groundwater to irrigate farms and pastures for the dramatic shrinking of its habitat in the drought-stricken West, where water shortages threaten many other species.
“Groundwater overexploitation is a huge threat to these fish and the source they call home,” said Krista Kemppinen, a scientist at the Center for Biological Diversity who authored the report.
The US Fish and Wildlife Service announced its 90-day positive finding this week.
“The petition presents significant scientific or commercial information indicating that listing the walleye fish as a threatened or endangered species may be warranted,” said the finding published in Tuesday’s Federal Register.
Threats to fish include impacts from agriculture, encroachment of aquatic plants, geothermal energy, lithium mining and climate change, it said. A full review of his condition is expected next August.
The lake valley’s groundwater levels have dropped as much as 2.5 feet (76 centimeters) a year over the past half century, causing a cumulative decline of more than 75 feet (23 meters) since 1973, the report said.
The Esmeralda County consultant hired to develop the water resources plan in 2012 warned that the Fish Lake Valley basin is “experiencing irreparable damage from water production in excess of annual feedback.”
“This overdraft is resulting in the collapse of aquifer storage,” Reno-based Farr West Engineering said at the time.
Nevada Farm Bureau Executive Vice President Doug Busselman said most local farmers and ranchers probably haven’t heard of tui chub. But there have long been concerns that water is being over-appropriated – meaning that, at least on paper, rights have been granted to more water than actually exists.
“Over the years that I’ve been down there, I’ve heard different accounts from domestic well owners who are worried about having to dig deeper wells,” Busselman said Wednesday.
The report should serve as “a notice for people to get informed and study it and try to find out what can be done about the underlying problems,” he said. “This isn’t the first report we’ve filed, and it won’t be the last.”
Basselman said federal involvement is often counterproductive because regulatory responses can take years.
“It’s a lot easier to work through a state process that deals with water rights laws versus having to deal with … a kind of endangered species law,” he said.
The report said climate change is contributing to threats to water supplies across the West that support fish like the one in Nevada.
Average temperatures are increasing, and eight of Nevada’s 10 warmest years since 1895 have occurred since 2000. Drought frequency and intensity are expected to continue to increase and snowpack to decrease 30-50% by 2100 in most basins, according to a 2020 state climate study.
Western fish already listed under the Endangered Species Act and facing increasing threats from drought include Chinook salmon in California’s Central Valley, Rio Grande silverfish in New Mexico, and San Pedro Gila walleye in southern Arizona.
The USFWS said when it listed the San Pedro Gila walleye in 2005 that it was one of only two native fish species left in the San Pedro River, which historically supported at least 13. The agency cited groundwater pumping for agricultural and municipal uses as contributing factor to the loss of Gila chub.
Kemp pointed to a 2020 study published in the online journal Nature Sustainability and cited by the U.S. Departments of Agriculture and Interior, which concluded that 53 fish species are at increased risk of becoming endangered or extinct due to runoff depletion of water caused mainly by cattle and fodder irrigation. crops in the western US.
“With water dwindling in the West, there could be a flood of applications for new aquatic species in the coming years as more and more aquatic species face extinction,” said Patrick Donnelly, the center’s Great Basin director. The lesser chub (another threatened subspecies) is just the tip of the iceberg.”