Fish Out of Water

IN THE SPRING of 2016, biologists at the U.S. Fish and Wildlife Service came to a terrible realization: The Yaqui catfish, the only catfish species native to the Western United States, was on the cusp of disappearing. After a week of searching, they could catch only two wild fish. They estimated that, at most, just 30 fish remained.

For approximately two decades, the last known Yaqui catfish in the United States had been kept in artificial ponds built in and around San Bernardino National Wildlife Refuge, on the Arizona-Sonora border, and at a local zoo. Creatures of rivers and wetlands, they had not reproduced. Still, federal and state biologists felt they had to try one more time. In a lastditch breeding effort, the agency gathered 11 fish and shipped them to a hatchery in Kansas. Within weeks, all of them died. Eventually, even the one geriatric catfish left on display at the Arizona-Sonora Desert Museum had to be put down.

Today, the Yaqui catfish, a whiskery-looking creature that evolved at least 2 million years ago and was once common enough for people to catch for food, is functionally extinct in the United States. There may be a few still hidden in Arizona’s ponds, but not enough to keep a population alive. According to the Fish and Wildlife Service’s 2019 five-year review of the species, it’s on the brink of global extinction; even as the catfish faces ongoing threats in Mexico, scientists know enough about the its basic biology to save it.

To people for whom “Sonoran Desert” conjures up images of steadfast saguaros or sun-struck lizards, the fact that a native catfish species existed in such a dry place can be surprising. In reality, prior to European colonization, the region supported rich waterways and aquatic communities. The current extinction crisis speaks to an uncomfortable truth: In a land of finite resources, every choice, big or small — irrigating an alfalfa field, taking a swing on a golf course, burning fossil fuels — means choosing what kinds of habitat exist, even far away from town. And that means choosing which species survive.

Now, the hunt is on to find more Yaqui catfish in Sonora, Mexico. But as the election season ramps up, the Yaqui catfish faces a new threat: The Trump administration is racing to complete the border wall before the 2020 presidential election, blasting desert mountains, tearing up old-growth saguaros and destroying the ancestral homelands and cultural resources of tribal nations such as the Pascua Yaqui, Tohono O’odham and Hopi. According to Laiken Jordahl, a staff member with the Center for Biological Diversity, wall construction will require 700,000 gallons of water each day.

To be clear, the Yaqui catfish is no jaguar. It’s no beauty; it’s not terrifying; its babies aren’t even all that cute. A reclusive