Endangered desert pupfish delays Colorado River conservation plans for Imperial Valley

ASH MEADOWS NATIONAL WILDLIFE REFUGE, NYE COUNTY, NEVADA - APRIL 29, 2022: A Devils Hole pupfish swims in a propagation aquarium at the Ash Meadows Fish Conservation Facility, Friday, April 29, 2022 in Ash Meadows National Wildlife Refuge, Nevada. Federal biologists have reported increased numbers of one of the world's rarest fish, the Devils Hole pupfish, counting 175, the most seen in a spring count 22 years. (Brian van der Brug / Los Angeles Times)
An endangered pupfish swims in a preservation tank. (Brian van der Brug/Los Angeles Times)

Plans to scale back water usage from the imperiled Colorado River have been hindered by a tiny fish no bigger than an index finger.

The Imperial Irrigation District in far Southern California had been gearing up to begin a water conservation program next month that would pay farmers to temporarily stop watering crops such as alfalfa and wheat in an effort to save supplies.

But those plans were put on hold after environmentalists raised concerns that dry irrigation drains could threaten desert pupfish, an endangered species that calls the region home.

Jamie Asbury, the water district's general manager, told the Associated Press the program has been delayed until at least June so that officials can determine a way to protect the fish while also reducing water use.

The IID is a key supplier for the agricultural region that grows most of the nation's winter vegetables. It is also consistently one of the top water-using regions in the state, and the recipient of California's largest share of Colorado River water.

The Colorado — long viewed as a water lifeline for the West — has been sapped by drought, overuse and climate change, and California and six other states are in tense negotiations about how to permanently cut back.

In the meantime, California has agreed to give up 1.6 million acre-feet of water through 2026. Nearly half of those cuts would come from the IID through the proposed conservation program and other efforts, agency officials said. (An acre-foot of water is enough water to supply up to three households for a year.)

A woman looks into a pond of muddy water.
Jessica Humes, environmental project manager for the Imperial Irrigation District, looks over a pond refuge for the desert pupfish recently in Imperial. (Gregory Bull / Associated Press)

The conservation program, which would cease irrigation on some fields for anywhere from 45 to 60 days, would help conserve water while still keeping the land in production. It is seen as a better option than year-round fallowing, which the agency employed between 2003 and 2017.

"Ag production amounts to 1 in every 6 jobs in the Imperial Valley and is the backbone of our economy," said Robert Schettler, a spokesman for the IID. "So a deficit irrigation program, if possible, would leave the ground in production and have a much less negative socioeconomic impact."

Read more: 'We can do better': Western states divided over long-term plans for Colorado River water

But the tiny pupfish, which typically measure less than three inches in length, could throw a wrench into those plans.

The species was listed as federally endangered in 1986. The fish were historically found in backwaters and sloughs along the lower Colorado River and in slow-moving seeps and streams in the Salton Sink basin, according to the California Department of Fish and Wildlife.

Habitat destruction and other changes have seen its populations decline rapidly, and most desert pupfish are now found only in the Salton Sea and in nearby shoreline pools and freshwater ponds — as well as irrigation drains.

"Drains are created for farmers to be able to convey irrigation runoff, and the pupfish decided it was a good place to live," Asbury told the AP.

Some populations also live in wildlife refuges, including one in El Centro that has been run by the IID for nearly 10 years.

Agency officials said that about one-third of the water spread on area fields runs off into irrigation drains, all of which lead to the Salton Sea. The environmental groups grew concerned that stopping irrigation on those fields, even temporarily, could cause the drains to dry up and threaten the fish habitat.

Their challenge was raised as part of the California Environmental Quality Act and the National Environmental Policy Act process, agency officials said. It could require the IID to obtain what is known as an incidental take permit before taking action that could negatively affect the fish.

"We are hoping that a 'take' permit won’t be necessary, as we are making adjustments and we continue to be in ongoing consultation with the state and federal agencies," Schettler said.

Read more: Mystery surrounds sudden increase in steelhead trout deaths near California water pumps

It's not the first time state water agencies have run up against issues with wildlife as they work to cut back water usage.

Earlier this month, environmental groups urged a federal court to intervene amid a dramatic increase in deaths of steelhead trout at pumps operated by state and federal water managers in the Sacramento-San Joaquin River Delta.

Officials with the Department of Water Resources and the U.S. Bureau of Reclamation said the presence of the fish at those pumps hampered their ability to capture and move more water south during the state's wet winter.

"DWR continues to take proactive measures and use the best available science to operate our water storage and delivery system to balance water supply needs while protecting native fish species," director Karla Nemeth said earlier this month.

The pupfish are known for their ability to live in extreme conditions, including a wide range of water temperatures and salinity levels. One species, the Devil's Hole pupfish that lives in Death Valley National Park, dwindled in number to just 35 in 2013 before making a small but meaningful recovery in recent years.

"A lot of them do live in these really bizarre drains, these agricultural drains," Ileene Anderson, senior scientist with the Center for Biological Diversity, told the AP.

"These fish are incredibly tough — they basically just try to find a space where they can carry on their lives."

The Associated Press contributed to this report.

This story originally appeared in Los Angeles Times.